HomeMy WebLinkAbout2-1-21 Climate Action Commission AgendaIowa City Climate Action Commission Age nda
Monday, February 1, 2020, 3:30 – 5:00 p.m.
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1. Call to Order
2. Roll Call
3. Approval of Jan. 4, 2021 minutes
4. Public Comment of items not on the Agenda
-Commentators shall address the Commission for no more than 3 minutes. Commissioners shall
not engage in discussion with the public concerning said items.
5. Staff Announcements
a. Action items from last meeting
b. Climate Action and Outreach Office Updates (see attachment)
6. Old Business:
a. Discussion of ideas to restructure working groups
b. Building Working Group Density GHG Memo (see attachement)
7. New Business:
a. Follow up discussion with HDR on the Methane Feasibility Study
b. Confirm meeting dates for 2021
c. Updates on working groups (see reports in agenda packet)
i. Buildings (Krieger, Karr, Soglin, Grimm)
ii. Transportation (Leckband, Giannakouros, Grimm)
iii. Outreach (Krieger, Fraser, Holbrook, Bradley)
iv. Equity/Adaptation (Tate, Hutchinson)
v. Waste (Bradley, Grimm)
8. Recap of actionable items for commission, working groups, and staff
9. Adjourn
If you will need disability-related accommodations in order to participate in this meeting, please contact
Sarah Gardner, Climate Action Engagement Specialist, at 319-356-6162 or at sarah-gardner@iowa-
city.org. Early requests are strongly encouraged to allow sufficient time to meet your access needs.
MINUTES PRELIMINARY
IOWA CITY CLIMATE ACTION COMMISSION
JANUARY 4, 2021 – 3:30 PM – FORMAL MEETING
ELECTRONIC MEETING
MEMBERS PRESENT: Madeleine Bradley, Stratis Giannakouros, Ben Grimm, Megan Hill,
Kasey Hutchinson, John Fraser, Matt Krieger Becky Soglin, Eric
Tate
MEMBERS ABSENT: Grace Holbrook, Jesse Leckband
STAFF PRESENT: Ashley Monroe, Joe Welter
OTHERS PRESENT: Morgan Mays, Marcella Thompson, Jeremy Cook
CALL TO ORDER:
Krieger called the meeting to order and introduced new member Megan Hill.
APPROVAL OF DECEMBER 7, 2020 MINUTES:
Fraser moved to approve the minutes from December 7, 2020.
Grimm seconded the motion. A vote was taken and the motion passed 9-0.
PUBLIC COMMENT OF ITEMS NOT ON THE AGENDA:
None.
STAFF ANNOUNCEMENTS:
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Action Items from last meeting: Monroe noted there were three action items to follow up on
from the last meeting. Gardner was asked to check with Wendy Ford about whether the TIF
funded initiative requires participants to disclose whether they're participating in the utility
funded energy efficiency programs. The City does include a question regarding that on the
application with a note that some projects may qualify for both types of funding, so moving
forward the plan would also be to follow up with the applicants on the question during the
approval process. Staff also spoke with Brian Gibbs from MidAmerican Energy to make sure
that participating in the program doesn't disqualify a business from participating in their program
and it does not. Monroe explained there was initially some concern about double dipping. For
example, companies applying to the City for a forgivable loan and then applying for a rebate on
the same project but the total amount of funding from the City and the utilities would be less
than half a million dollars and most of the projects would be exceeding a million dollars so the
consensus was that it wouldn't be a concern. Additionally, the City’s pool of funds is coming
from a different set of funds than the utility programs so the companies that are utilizing the TIF
rebate program have already paid into that into that pool with their tax dollars.
Staff also looked into whether the implicit bias training was recorded and able to be shared in
the future. Unfortunately it was not recorded but the City offers it on a frequent basis generally,
so future opportunities for more bias training will be made available to the Commission
members.
Finally, Monroe said Gardner drafted a description for the idea about restructuring working
groups and shared it with Soglin and Krieger to review in advance of today’s meeting. It was
included in the packet for the Commission's consideration.
Updated Action Plan Report: Monroe briefly stated that they are pleased that all of the items
that were identified as something they wanted to initiate in 2020 are either in development or
underway, and a couple of them are deemed as complete. For example, the creation of the
climate ambassador program was identified as a completed project because the first round of it
has been done and then further action on that can be developed in the future. Establishing
preferences for an electric and fuel-efficient vehicle purchasing policy has also been marked as
complete. Those revisions have been made and then further adaption of data can be expanded
on in the future. Monroe noted they have a couple of things going with the community
stakeholders in the buildings section that are focused on identifying opportunities for incentives
for both residents and the development community to try and focus on energy efficiency in
buildings. They’ve made progress on the transit study, which took place over the last year and a
half, and the results of the study were presented this fall. The actions from that study outcome
will be implemented with changes coming in the summer. Monroe noted staff would invite any
additional feedback from the Commission about how to provide outreach to the community
regarding the transit system changes, or other incentive programs, which they’ll be focusing on
into 2021.
Monroe explained there are a lot of the projects still in development and underway in 2020 that
they will still be working on in 2021, and staff will continue with the help of the Commission and
the working groups and community stakeholders. Staff has tried to balance the introduction of
these new items, so the things that are in Phase Two of the Action Plan are basically estimated
with a time to initiate. Staff wanted to ask the Commission how comfortable they are with what
staff has identified and believe is appropriate to introduce in 2021. Staff also identified a couple
of projects to start in 2022 and will continue to build on things done in 2020. Monroe asked if the
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Commission has any concerns about the timeframe or projects in 2021.
Krieger said he doesn’t have any issues with the timeline, noting staff has done a good job of
outlining the reasoning behind which items are accelerated and such. He commented on the
benchmarking and the other things associated with the incentive programs or the TIF programs,
acknowledging those take time to work through, so he appreciates that the staff has
incorporated the reasoning and the updated timeline.
Giannakouros agreed, saying this is all impactful measures. The one thing that may or may not
impact the local level is with all the federal changes happening in the new administration.
There's going to be an emphasis throughout every aspect of federal policy to be climate-
oriented to some degree. Therefore, as policies and incentives and mandates roll out, the
question becomes how does that impact this work – how does it enhance it or whether it doesn't
change how they go about doing this stuff. He stated he feels this is something to keep an eye
on and understand, saying within the next six months they may have to rethink a ton of stuff.
Monroe said that was really good feedback from Giannakouros and they will continue to be
mindful of that at the federal and state levels as they are entering into a new legislative season
at the state as well. As anything evolves the Commission will need to be sensitive to those
changes, and staff will leave it again to the Commission to also to provide some guidance on
anything they think staff should relook at and modify based on those new changes.
Monroe noted that they are looking at the objectives scheduled to start in this year she is
energized by the fact that a great majority of them really center outside of the buildings. The
buildings section is policy and project heavy, but further down in work plan they're talking about
a lot of equity issues. She said she knows the Commission has been very sensitive to how to
integrate equity principles and standards into each of the actions. So something that staff is
especially attuned to going forward in this year is really continuing to build data for delving
deeply into those things. They are already starting conversations with public health, for
example, as well as other community organizations about how they can better partner to
address both social issues and also climate issues as one. Monroe stated staff is excited about
that and the real concentration of where they're going with these projects. Nothing will get done
without an intent and a focus on the equity components of each of the proposals that they'll put
together.
Krieger noted to that point there are quite a few references made to the equity report and he
doesn’t know if a final version of that document has made it to the full Commission. It might be
good to have that as a point of reference if they’re going to be talking about how working groups
get restructured and how outreach is done. To have that as a as a guidance would be really
good.
Monroe agreed they could certainly provide the Commission with what they have, noting they
have been working on an amplification of that final equity report that she thinks will more
specifically meet these needs and they'll make sure to share that with the Commission. Also, as
an added bonus, she said staff is nearly there with coming to an agreement with the firm to help
with a communications strategy and as part of that communications strategy there's an
assessment specifically geared towards equitable outreach and building relationships.
Fraser commented he really appreciated Giannakouros’ comment and thinks they’re all on the
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same wavelength that this is like a strategic plan and is a living document, and as such they
need to maintain the discipline of working through it as it's published, but at the same time have
the flexibility to change it as conditions require those changes because the political atmosphere
that's coming up is a bit unknown. Everyone needs to keep their eyes and ears open and make
sure that based on government policy the new policies that they put into place are flexible and
can be changed as required.
Krieger also added they need to evaluate new research as it becomes available as well, saying
there's many external forces that they need to be able to manage as part of the overall plan.
Tate stated their conversations around the topic of equity have deepened over the last year and
he is glad to see progress with this climate analyst position who could start looking at some of
the mapping and distributional dimensions of equity. Outreach has been mentioned as a key
strategy, but Tate also noted there's some other dimensions that they might consider as they go
along. One of them came up earlier, which was the procedural or eligibility with the tree planting
plan and who could have access to it. He stated there's a broad swath of ways that they can
look at distributional effects, but it tends to be something that's after the fact with some of these
processes in who can participate, who's eligible and what barriers are there. He just wanted to
make sure they keep that in mind and to use the tree issue as an example.
Monroe noted they don't have the December update of the report on the website yet, so they'll
get that up as well as the 2021 plan.
Krieger noted that, similar to the equity report, staff mentioned the transit study
recommendations. He said it might be good to distribute those as well, or at least the link to
where those are located, because it was presented to Council, and having ready access to that
as well would be handy.
Monroe agreed and said staff will be mindful of that and include some of the links within this
report if those reports live somewhere on a pretty permanent basis on the website.
OLD BUSINESS:
Discussion of ideas to restructure working groups: Krieger tabled this item to later in the
meeting to move onto new business due to time constraints.
NEW BUSINESS:
Nomination and Election of Commission Chair and Vice Chair: For the position of Chair
there were two accepted nominations, Fraser and Giannakouros.
Fraser stated he is humbled by the talent among this group, and if he were the chair he would
certainly count on these talented people in this organization who have a lot more fresh and
diverse ideas then he perhaps has. As chair, he feels being a good listener is one of the key
attributes, particularly of this Commission and particularly today with what's happening politically
and economically. So many aspects of that, equity being one, require a huge focus and is very
challenging. Fraser also acknowledged the staff does an awful lot of work and he wants to
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make sure that the Commission is not dumping everything on staff and are stepping up and
doing the fair share as Commission members. He reiterated during these times there are a lot of
challenges coming up but also a lot of opportunities. He is excited about what may come with
the new administration. He feels there needs to be a lot of emphasis to sell what they're doing
to the state legislature. Iowa City needs to do this right so other cities follow, not just the larger
cities, but every community in the state of Iowa needs to be on board to make a big difference.
Giannakouros stated he agrees with Fraser that this Commission has a responsibility to try to do
things, saying it is easy to get overwhelmed and busy but with the right leadership to support big
efforts change can happen. He added if they thought harder about what are the levers they
need to pull to make this Commission execute on what it's supposed to do, like cutting carbon
emissions in an equitable way, and really not losing sight of the fact that something that sounds
really good and may not take a lot of effort for those endeavors. Other things are big, and
they're hard, but the return to effort is there – things such as a light rail for North Liberty to Iowa
City, that’s a big deal and a game changer and this Commission should be advocating for
something like that. Simpler things such as behavior change in the community are good, he
said, but they know what moves the needle. They've had enough history of doing this kind of
work to understand where they should focus their attention and where they shouldn't. Also with
equity, it's simple to say that every single policy this group goes after should be at the outset
designed to understand the impact it has on people who are powerless, who are not at the
table, and who by design really don't benefit from carbon emissions, the upside, and the profit,
yet they bear the consequences. Those things are big, but supporting City staff and making sure
things are organized is important. If Fraser wants to take that on and do that, Giannakouros
would support him entirely. He said he supports Fraser for the role as chair, so he no longer
wishes to be nominated for chair.
A vote was taken and Fraser was elected as Chair (9-0).
Giannakouros was nominated for Vice Chair and a vote was taken and Giannakouros was elected
as Vice Chair (9-0)
Presentation by HDR on the Methane Feasibility Study: Joe Welter, Senior Civil Engineer
for the City of Iowa City, said he got the joy and pleasure to work on a couple of the action items
that were in the Climate Action and Adaptation Plan as he has had a lot of experience in the
past with environmental engineering. They had the opportunity to go through and screen a lot of
different consultants and were very impressed with the team that is going to present today from
HDR. Presenting today are team members from several of their offices in Iowa, Nebraska, and
Toronto, Canada. They have had a lot of experience with these types of studies with other
municipalities and other groups, and Iowa City had them look at the two different facilities, the
wastewater treatment plant and the landfill, which produce an abundance of the biogas
methane. Morgan Mays is the project manager for HDR and they also have Marcella Thompson
and Jeremy Cook here tonight to discuss the study. Welter noted these were the three main
people the City worked with from HDR but there was a plethora of very talented people at HDR
that worked on this study for the City.
Morgan Mays (Project Manger, HDR) began with an introduction for their team. He serves as
the project manager on this project and is in the Coralville office today, but also works out of the
Cedar Rapids and Wilton offices. He has been with HDR for a couple years now and has
covered a wide gamut of projects from climate studies to floodwall projects, to building bridges
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and roads.
Marcella Thompson (Director of Sustainability and Resiliency, HDR) is from the Omaha,
Nebraska, office and has worked in the sustainability field for just about 20 years.
Jeremy Cook (Senior Economist, HDR) is also from the Omaha Nebraska office and the lead for
this part of the country on sustainable return on investment modeling that was used here for the
City of Iowa City.
Mays gave a quick background on HDR. They are worldwide, working in over 40 countries, with
ongoing projects across the world. They were established back in 1917 and now have 10,000
plus employees and a couple of those 200 offices are right here in Iowa. Mays noted the City
has been a leader in environmental stewardship and sustainability for decades, what began as
resource conservation and energy efficiency back in the 1980s and has really evolved into more
of a focused effort to take action on climate change now. Back in September of 2018, the City
Council adopted a Climate Action and Adaptation Plan and set goals for City-wide carbon
emission reductions. Mays believes that goal was originally set at 25% to 28% from 2005
levels, reduce that down by 2025 and then 80% by 2050. The bar actually was raised recently
by this Commission and City Council and by a unanimous resolution to increase reductions up
to about 45% now from 2010 levels by 2030 with a net zero goal for 2050. This is a big push,
very proactive approach, by the City. This project’s general purpose was to evaluate those
strategic alternatives that would efficiently capture and beneficially use or reuse methane from
both the wastewater plant as well as landfill operations so as to enable the City to take that step
forward for implementing their Action Plans. This project then was developed and started to
focus on two priority action items: action item 3.7, which is a study to efficiently capture and use
methane from the wastewater operations, as well as action item 3.8, which is, conversely to
study the energy generation from the landfill methane. Mays noted this also tied back into a
couple other action items such as frequency to increase the composting of organics, those
organics certainly lead to the generation of methane, as well as action item 1.4 to increase the
onsite renewable energy systems and electrification. This project really tied all those action
items together and looked at it as a cohesive picture. The analysis also included a triple bottom
line approach, or SROI, that looked at all of the capital investment needs, the lifecycle
greenhouse gas impacts, as well as the energy return on investment. Cook will talk a little bit
more on that later.
Mays next discussed a brief history of the project. They started this about a year ago, last
February. They provided a waste shed analysis, looking at the solids and organics that are
currently managed by both facilities, as well as what an incremental increase of waste could do
to that biogas production. Then they looked at both facilities as a whole and looked at what their
existing and future conditions of each facility was going to be, and the opportunity for any
recovery and reuse of biogas through the study period, which was looking at a 30 year time
period, from 2020 roughly to 2050. Then in May they provided a biogas utilization technical
memo that really evaluated all the different options that they consider for utilizing that biogas at
both facilities, and included a natural gas pipeline injection option, electricity generation, and
then also a natural gas replacement. In August, they tied this all back together into the report
that was in the agenda packet, that evaluated those current and future reuse alternatives and
considered the greenhouse gas emission reductions to energy return on energy invested and
the SROI framework.
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With regards to the existing conditions at the two facilities, the wastewater treatment plant itself
is the largest user of electricity and natural gas within the City. It processes just under 11 million
gallons a day. Methane there is produced predominantly on site during that anaerobic digestion,
and then its reused in on-site boilers that heat the biosolids and promote that digestion. The
remainder is flared off. There is about 80 CSM is produced currently. The landfill serves
Johnson County, Kalona, Riverside, and manages approximately 130,000 tons a year of waste.
Food wastes are approximately 25% of that total waste mass and about 35,000 tons. Methane
produced there during the waste decomposition process is collected and then flared. Current
levels have that around 945 CSM, so there really is a true order of magnitude difference
between the wastewater treatment plant and the landfill, which something to keep in mind when
as they look at alternatives.
Thompson reiterated the feasibility study was included in the agenda packet and that she just
wanted to point out that throughout the rest of presentation they’ll see little footnotes that
reference specific sections to that study. Thompson said she would be reviewing the
alternatives as related to both the facilities, the waste diversion scenarios, and the greenhouse
gas emission impacts that they built into the SROI model that Cook will talk about. She
reiterated that of the two facilities the landfill produces orders of magnitude more biogas to work
with, which certainly factors into the greenhouse gas emission reduction potential. Thompson
noted what is interesting about these facilities, and that they see this across cities, is that while
they in themselves often represent a very small part of the City's greenhouse gas inventory,
they are also enablers of change. So in addition to managing emissions at the site, they can
also offset emissions, which is why reuse is such a strong potential.
Thompson said the first option they looked at, which they will refer to as “Alternative One” and
“One-A”, is co-digestion and pipeline injection at the wastewater plant, and “Alternative One-B”
is the same thing: pipeline injection at the landfill. This is where they would take that biogas,
clean it up to pipeline quality, inject that into the pipeline to a standard that can meet the
Renewable Fuel Standard, and sell that on the grid market. The City would benefit through
some direct emission reduction on site, but there would not be the same offset within the City
boundary as those purchasing the grid credits would get the reduction out in their realm. The
second alternate is electricity generation. This also applies to both the wastewater treatment
plant and the landfill. She explained this is the same concept but at different scales at both
facilities. They would take that gas, clean it to a quality that it can be used in a generator on site
and then in both cases they assume that the quantity of electricity generated is greater than that
any of those facilities can consume so it would involve a partnership with the utilities to put that
back onto the grid. They assume that through that agreement, the City would be able to retain
that renewable energy credits, which would help offset a portion of the City's electricity use with
that onsite renewable energy generation. The last option, “Alternative Three,” is natural gas
replacement, and that would only apply to the wastewater treatment plant. Similar to pipeline
injection, this alternative is again where they’re cleaning that gas up to an equivalent to natural
gas, but it would be used on site to displace natural gas that used and there will be realized cost
savings as well as the greenhouse gas reduction benefit. Thompson reiterated in all cases when
they’re thinking about biogas, it is considered a biogenic carbon source ,so when they're
composing the City inventory, biogenic carbon is recorded separately and they would realize
that reduction related to natural gas or electricity generation.
Thompson also noted as they walked through two facilities with three alternates, the other key
factor was a lot of the City’s climate action strategies are interrelated and certainly in the case of
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organics management, and what the City pursues from incremental diversion will impact those.
They looked at three scenarios, one is the business as usual, how much organic material is
being diverted today. They also looked at a scenario which they called the “1500 tons per year”
scenario, which represents the incremental capacity of the wastewater treatment plant to co-
digest those organics. The second one is a low diversion alternative, which is a 20%
incremental capture of organic material which equates to about 8500 tons per year. That would
be in pursuit of the organic’s recovery climate action strategy. Thompson stated they looked at
these scenarios, specifically in those earlier studies, in terms of how would that impact the
methane generation both at the wastewater plant and the landfill, and then they ran through the
SROI analysis for both facilities and the three alternatives for these three different scenarios.
The last thing Thompson wanted to touch on is the greenhouse gas emissions impact that they
considered, which is shown on table 10 within the report. They looked at three different
greenhouse gas emission impacts. One is the direct emissions which takes energy and results
in emissions to add additional equipment to scrub the gas to run the generators, so there is
some invested carbon in those technologies. They looked and accounted for any incremental
emissions from those processes to beneficially reuse the gas, and they also use the EPA war
model to consider lifecycle cradle-to-grave impacts. She noted that they went from the baseline
business as usual, what is being diverted, to what happens if they pull that out of the landfill and
co-digest that or if they composted that, et cetera. That accounted for the lifecycle emissions
from those landfill diversion alternatives. The final one is avoided emissions, particularly in the
electricity generation, the natural gas displacement, there are avoided emissions from not
having to procure that electricity from the grid, or by natural gas, and combusting that, so those
were accounted for as well. That's one of two key inputs into the SROI model, the second one
was also the energy return on investment.
Cook next discussed the energy return on investment which is basically a fairly straightforward
calculation, it's a ratio of the energy output that's gained against the energy input that's required.
It can be thought of as a ratio of how much energy do they get versus the energy required to
produce that level of energy output. Similar to the greenhouse gas emissions, for this analysis,
they worked through what the equivalent amount of energy that's delivered is, whether it's
natural gas or electricity, and then put those all in common units and compare the energy output
minus any of what they call parasitic energy, or the energy used to produce that level of output.
Then they created a ratio of that against the direct energy input into the calculation that gave a
life cycle. They also competed this over the lifecycle of the project, so over a 30 year period,
that ratio shows the rank and the overall score. The higher the score, the better the EROEI.
Cook said they have the ranking of those for all 16 alternatives. Cook noted he has touched a
little bit on SROI or sustainable return on investment and showed a table of the biogas utilization
report. What SROI is, is a triple bottom line economic analysis framework that came out of the
Clinton Global Initiative in 2007. It's something that HDR developed in partnership with the
Clinton Global Initiative, as a way of evaluating broader climate and sustainability and resiliency
effects of projects beyond just traditional cost benefit analysis frameworks. It relies on a few key
principles, one is a triple bottom line accounting of impacts. Economic, environmental, and
social are the key bins there, and they also try and monetize as much of the range of effects as
possible. In this case, for this project, they focused on electricity generation benefits,
greenhouse gas emissions against lifecycle costs. But then another aspect of this is to try to
incorporate in as many of both economic or monetize values as they can, and also key
performance indicators. Cook noted they can't always monetize everything, saying even as an
economist he likes to try and monetize effects and put them into general comparisons because
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that gives a common unit for comparing impacts, but it can't always be done. The EROEI as well
as the greenhouse gas are the two key performance indicators that really relate to the effects
and goals of the Climate Action Plan here for City of Iowa City. Cook said he basically will try
and present as much as he can for both the performance indicators, non-monetary effects as
well as economic values.
Cook showed a summary report (from table 12, page 28, of the feasibility report) and pointed
out basically they had taken all the results from their economic framework, their benefit cost
ratios, and they computed the EROEI as well as the greenhouse gas reductions and converted
everything to an index. They then took those indexed values and combined them into basically a
composite score that helps prioritize each of the three alternatives for the different diversion
scenarios at both the wastewater treatment plant and the landfill location. Camp noted for
example, if they just undertake pipeline injection, no diversion at the landfill location, that would
be “Alternative One-B.” That alternative is given a score of 0.8, versus comparing to the low
diversion scenario, which has a score of 0.86. Basically what they're saying here with these
alternatives is the higher the score, the better the alternative, and that basically gives a ranking
or hierarchy in terms of the outcomes. They also show the same outcomes basically doing
nothing at the landfill and doing only actions at the wastewater treatment plant. Following this,
they recognize that there's potential for combine ability of all these actions. For example, they
could do something at the landfill location, maybe some electricity generation, and then do
something at the wastewater treatment plant, following that same organization of alternatives.
He showed how they need to follow the alternatives, because it's important to note that they've
got to stay within diversion scenarios when comparing actions and trying to determine what is
the best strategy. If they were to just think about the City staying at no diversion but doesn't
increase any incremental diversion over where it's at, then they can show what is the best return
is actually doing it first at the landfill location, doing pipeline injection, the alt one b, no diversion,
but with a score of 0.8, and then that could be combined with pipeline injection at the
wastewater treatment plant location for a combined score 1.02. Camp pointed out if they walk
back through the individual results for EROEI, benefit cost ratio and the greenhouse gas
emissions, they can see how those scores combined and get to the 0.8 and 0.23. Similarly, as
they go up to the 1500 ton per year diversion they have a similar construction but this time it is
actually the highest score because they're getting some value back in terms of electricity
generation from the pipeline injection at the landfill as well as adding the electricity generation at
the wastewater treatment plant. He stated that also holds true with the low diversion scenario, if
they were to increase up to 8500 tons per year in terms of diversion, they would see again a
score of 1.37, basically the highest ranked alternative which again includes pipeline injection
and electricity generation. Cook noted this is all summarized with an explanation of how all this
works in the in the feasibility study, and that section of the report lays out basically how to follow
the logic for the table and combine alternatives.
With that in mind, they can see where the highest ranked alternatives are, so the next question
that came out of this was what the financial implications of this are. Is it financially actionable?
Cook said they added a supplemental analysis at the City's request to do like a financial
payback period to see how this would all pencil out. Cook showed a quick summary of the
financial analysis, and again pipeline injection at the landfill is the best alternative in terms of if
they're just going to do one alternative initially. From a financial viability standpoint, it is actually
the only alternative that generates a payback on its own within 10 to 30 year period. Camp did
note however all of these alternatives can break even with a bond term of at least 18 years,
which is a fairly robust result considering a lot of bond terms go as far as 20 to 25 years. For all
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of these alternatives operating costs do exceed the financial benefits, so that is the thing that's
really holding them back here in terms of the other alternatives. They did identify that there is
potential that if on the electricity side the City could get $20 million in grant funding, or if the City
were able to negotiate electricity sales buyback, then there would be potential for electricity
generation at the landfill to break even within a 30 year period as well.
Giannakouros asked when discussing injecting if a high cost to clean up the water out of this
natural gas and then get into the pipeline is where the big cost comes in. Could they use it there
onsite in a boiler? Welter replied it not the water, it's the things that are in the gas other than
methane that need to be scrubbed out of it. At the wastewater plant they have a lot of toxins and
so there's special equipment that has to be put into to get it to the point where they can either
put it in equipment and burn it and generate electricity with it without damaging that equipment.
Or to get it to the quality that it needs to be to inject it into the MidAmerican pipeline, it has to be
of a certain quality. It's all the extra things that are in it, because of the types of organics and the
types of wastes that are there.
Giannakouros acknowledged obviously they're cleaning up the gas so that it can be put in a
pipeline to a higher quality. However, keeping it on site and generating electricity, that's
expensive versus cleaning it up. Welter said they will have to clean it up either way, whether it is
used on site or off site, because it has to be to a quality where they can inject it into the pipeline
meeting that requirements, or to a quality where they can actually burn it in the equipment that
they have on site, a turbine or another system, and not damaging that equipment.
Mays summarized and laid out the potential next steps. The Commission all received a copy of
the report, he believes. His whole team is going to be available at the next meeting to field any
other more in depth questions and give the Commission the opportunity to go through that
report in a little bit more detail. In a general summary, she said, this project looked at 18 unique
possible combinations in addition to just those three scenarios at each facility. He did want to
point out that when they look at low diversion, that low diversion is at 8500 tons a year. That
actually exceeds the capacity that the existing wastewater treatment plant can take, so that
does require a separate co-digestion facility or an expansion of the existing digester facility. He
explained that is part of why those costs throughout the report are so high on those items. Mays
noted the first step is really for the City and the Climate Commission to come to terms on what
targeted diversion scenario makes the most sense. The report lists a couple different
alternatives and options, and they really want to be able to narrow down the list so then they
can look at what the next steps would be and dig further into the cost estimation. He added it is
important to remember this is the study level. Those cost estimates that are put together have a
fair amount of contingency in there to cover some of the unknowns that are certainly numerous
at this point in the process. Once they have more of a clear path forward, they can start to
connect the dots between other projects and maybe there's a chance to align projects, find
some efficiencies and costs options to minimize that capital increase at the beginning. Mays
noted the path forward is listed in both the executive summary of the report as well as at the end
of the report and believes they offer at least an idea of what needs to take place for the City and
the Commission to be engaged as well as the community level. Maybe there's public private
partnerships that certainly come into play here to figure out a way to bring some of these action
items to reality. But the next step will be more of a conceptual design process.
Soglin thanked them for writing something that's incredibly complex into something that they
can start to grasp. She did glance at some pages in the study but was wondering if they
Climate Action Commission
January 4, 2021
Page 11 of 12
11
included case studies or examples that are in existence in other cities. If not, she asked if they
can provide some links and some examples. Mays replied they didn't provide any case studies
but they can give that some thought and get some.
Welter stated City staff did a lot of things leading up to the development of the request for
proposals that they sent out and got back many responses from different consultants. They
ended up interviewing three different teams and HDR was one of those. Staff went to Dubuque,
Des Moines, Muscatine, and Amana and looked at a lot of other operations that were doing
things that they thought they might be interested in. So City staff saw some of those case
studies but didn't include that in the study because the idea of the study is for it to be an open
sandbox and not some sort of preconceived notion for the consultant of what the City thought
they wanted. The City wanted the consultant to be able to use their expertise to tell us what the
most feasible options are. Soglin appreciated that but wonders if Staff would be willing to share
with the Commission in the future their thoughts on what they saw when they went to other
cities compared to the alternatives in the study.
Thompson noted that all three alternatives that were looked at are all viable, they're proven
technologies. She thinks some of the things to think about strategically are things like electricity
generation, does it meet the goal of doing it renewable generation onsite with renewable natural
gas. They also know at the same time that the grid is changing, that's not a static comparison,
and they did account for that in their analysis. As utilities continue to increase their renewables
and the grid keep moving they have to think about that in the long term. She also added pipeline
injection is essentially the same as natural gas displacement but instead of doing that onsite for
their own equipment, they're putting it into the pipeline so that there's benefits outside of Iowa
City that are being realized as people purchase that Renewable Fuel Standard.
She noted it was mentioned at the beginning of this call there may be some change across all
fronts from a federal perspective, so how that affects Renewable Fuel Standard changes is
anyone’s guess.
Tate wanted to raise a question to be answered at next month’s meeting around the SROI
analysis, which is positive addressing the triple bottom line, but he thinks in reality here is mostly
focused on environmental and economic dimensions of it, so wondering to what extent are
social benefits and costs and burdens relevant or played a role in the analysis.
Monroe agreed the consultants will return at the next meeting, so the understanding is that the
Commission will take time to review the materials and understand what the options are, and
what exactly was done. They know that the potential projects are complex and they're extremely
expensive. This is a long-term view or goal. This study was an aspirational goal of the Climate
Action Plan, but if the Commission wants to recommend some action, either the incremental
actions or planning for a larger project, the Commission is the recommending body to Council.
Welter acknowledged it was an excellent presentation. They got some 300 pages that went into
the final study for different parts of that study, so this presentation was whittled into some of the
more important aspects of that. He also wanted to note Tate’s comments on the SROI and that
was one of the specific reasons the City picked the HDR team is because they had this
approach, none of the other consultants brought such a broad reaching approach. Most of the
other consultants ultimately were project based, and that approach was going to determine
whether alternative was feasible mostly on economics. HDR was able to quantify in these
indexes what the impact was on net greenhouse gas and what the impact was on net energy.
Climate Action Commission
January 4, 2021
Page 12 of 12
12
Additionally, their approach also brought in some of these health and community aspects, just
based on the merits of what the SROI model was.
Update on Working Groups: Tabled to next meeting due to time constraints.
RECAP OF ACTIONABLE ITEMS FOR COMMISSION, WORKING GROUPS, AND STAFF:
Krieger noted next meeting's agenda will include the working group restructuring discussion, in
addition to a follow up discussion for the methane project. He also reminded everyone if there
are any working group meetings between now and the February meeting, make sure to get the
report summary of the activities to Gardner and Monroe by the last Monday of January.
ADJOURNMENT:
Soglin made a motion to adjourn.
Giannakouros seconded the motion.
A vote was taken and the motion passed unanimously.
Climate Action and Outreach Office Updates: Dec. 2020/Jan. 2021
Recent Activity
Community-wide Climate Action
• TIF-funded climate action incentive program underway
o Application portal opened, first project to be submitted
o Ongoing discussions with MidAmerican; projects that qualify for their rebates will not be
disqualified by participating in TIF-funded opportunity and, when combined, can have
up to 75% of project cost covered.
• Smart Series partnership with Iowa City Area Business Partnership
o Four dates selected Feb. 9, May 11, Aug. 10, and Nov. 9 for virtual presentations on
climate action for area businesses
o First session will focus on energy efficiency rebates and climate action grants
• Green Iowa AmeriCorps
o 207 audits/Home Energy Kit completed so far
o 69 education/outreach events so far
o Application to host a team in 2021-2022 successful
o AmeriCorps team working with upcoming Linn & Johnson County Grow Solar initiative
• Energy Efficiency Building Projects
o Builder/project identified to showcase energy efficient home in Parade of Homes
o Working with Neighborhood Services on energy efficiency demonstration rehab project
• Earth Day Neighborhood Energy Blitz
o Door-to-door campaign will utilize AmeriCorps members, high school environmental
clubs, and Climate Ambassadors
o Staff committee formed to assist with program design
o In communication with South District neighborhood as possible pilot site
Marketing RFP
• In negotiations with consultant over finalized scope/contract – going to Council for approval in
Feburary
• Project will include a vulnerability analysis for populations in Iowa City and related
communications strategies
• Compiling all climate-related communications and marketing collateral in anticipation of project
start in February
Climate Ambassadors
• Second cohort schedule to participate in training Feb. 3-March 24
o Drawn from pool of previous applicants
• Application portal for third cohort scheduled to open March 22 with next training to commence
in late April
Current Grant Projects
• IEDA-Eastern Iowa EV Readiness Planning
o Both virtual stakeholder events held in January had high attendance and participation
o EV 101 presentation/project update available for viewing at https://youtu.be/0qUkZRi-
4ZQ
o Outreach has begun to multi-family housing landlords for barrier analysis
• Heartland Carbon Sequestration
o GIS-based Carbon Management tool under development and nearing completion
Staffing
• Onboarding process to start Feb. 1 for new Climate Action Analyst
Ongoing Projects
Equity Outreach Program
• Collaborating with Equity and Human Rights Division on a Black History Month guest speaker,
Richard Mabion, on fostering multi-racial partnerships for climate action and addressing
historically disparate access to sustainability resources
• Outreach underway to Community Based Organizations (CBO) utilizing updated stakeholder list
• Shortened equity report being drafted for review
Implementation of Accelerating Iowa City’s Climate Actions, tracking and reporting
• Planning/scheduling underway for 2021 (Phase 2) goals
Reporting and Metrics
• Anticipate analyst beginning data compilation for 2020 community-wide GHG inventory/CAAP
metrics
Communications (with part-time Sustainability Communications Assistance)
• Ongoing monthly Sustainability Newsletter
• Climate Action Quiz launched in January newsletter: www.surveymonkey.com/r/G2PQ893
o 124 quiz takers to date, roughly 1/3 provided email address to have chart sent to them
showing their areas of high engagement as compared to emissions impacts
o Analytics collected on quiz participation can help inform future marketing plan
Municipal Energy and Climate
• Data collection for municipal utilities ongoing
• Tracking water usage of municipal facilities
• Municipal GHG inventory reporting (~ every 5 years)
• Regular meetings with City departments
o Working with staff to incorporate GHG reductions and increase sustainability practices
within City operations (new analyst position will take over these responsibilities)
Ongoing Sustainability Groups and Committees
• Urban Sustainability Directors Network groups
• Heartland (Midwestern) Monthly calls, annual meeting
• Johnson County Sustainability Working Group, quarterly meetings
Draft Proposal for Climate Action Commission Working Group
Restructuring
Currently, the Climate Action Commission has five working groups focused on different aspects
of the Climate Action and Adaptation Plan (CAAP) for Iowa City: Buildings, Transportation,
Waste, Equity/Adaptation, and Outreach. Two of these groups, Buildings and Outreach, have
regular monthly meetings, while the other groups have experimented with meeting on a
monthly, quarterly, and/or as-needed basis. Recent discussions about restructuring the working
groups have explored options to help make more efficient and productive use of the working
groups, some of which have struggled to find and maintain a good work flow.
Two ideas were brought forth in the November meeting of the Climate Action Commission to
explore. The first would be to allow the Transportation and Waste Working Groups to stand
down or dissolve, as the majority of the projects identified in the CAAP in these areas are
currently undertaken by City staff in departments responsible for transportation and resource
management services. A new working group could then be formed to review adaptation plans
and actions in other communities with a goal of making recommendations for the next CAAP
update, a project not currently assigned to a specific department/City staff . The Outreach
Group would continue to function as it currently does, and the Building Group would
potentially revert to meeting approximately every other month instead of monthly until
another major project is assigned. The Equity Working Group would focus primarily on equity
while allowing the new Adaptation group to assume that half of its responsibilities. All
Commission members would have the opportunity to move or stay in the working group(s) that
most aligns with their knowledge and interests. Once the Adaptation group completed its
project, it could then stand down until again needed.
The second idea brought forth was to move toward a project-based model for forming new
working groups. Specific projects needing attention and input from Commission members
would be identified, and then representatives from some or all of the five current working
groups would be assigned to this subcommittee, so that perspectives related to buildings,
transportation, waste, outreach, and equity/adaptation could be brought to bear on the
projects as needed. Once the projects were completed, the subcommittee would dissolve. This
model would require members to participate in both the current working groups as well as the
project subcommittees to which they are assigned.
5815 Council Street NE Suite B Cedar Rapids, IA 52402-5893
(319) 373-2536
hdrinc.com
Biogas Utilization
Feasibility Report
CAAP – Methane Recovery Feasibility Study
Completed by HDR Engineering, Inc. on behalf of
the City of Iowa City, to support the Climate Action
and Adaptation Plan (CAAP) and the associated
Action Items 3.7 and 3.8.
Iowa City, Iowa
December 30, 2020
VERSION: 2
ii
Contents
Executive Summary .............................................................................................................. ES-1
1 Introduction ..................................................................................................................... 1
2 Project Background ........................................................................................................ 1
2.1 Climate Action and Adaptation Plan ...................................................................... 1
2.2 Feasibility Study .................................................................................................... 2
3 Renewable Natural Gas as a Resource ......................................................................... 4
3.1 Renewable Natural Gas - Environmental Attributes as Vehicle Fuel .................... 4
4 Description of Project Alternatives ............................................................................... 9
4.1 Alternative 1: Natural Gas Pipeline Injection ......................................................... 9
4.2 Alternative 2: Electricity Generation ...................................................................... 9
4.3 Alternative 3: WWTP Natural Gas Replacement ................................................... 9
4.4 Alternative 4: Composting ................................................................................... 10
4.5 Organics Diversion Scenarios ............................................................................. 10
4.6 Estimated Costs .................................................................................................. 12
4.7 Description of Impact Categories ........................................................................ 13
5 Summary Economic, and Environmental Impacts of Alternatives ........................... 24
5.1 Findings and Insights .......................................................................................... 27
6 References: .................................................................................................................... 30
Figures
Figure 1: SROI Triple Bottom Line Accounting ............................................................................. 3
Figure 2: EPA RFS Nested RIN Categories and Volumes ........................................................... 5
Figure 3: Historical RIN values From the EPA from 2015 Through August 2020 ......................... 6
Figure 4: California LCFS Market History ..................................................................................... 7
Figure 5: PhysRNG Value Considerations .................................................................................... 8
Figure 6: Organics Diversion ...................................................................................................... 11
Figure 7: Lifecycle Cost Structure and Logic Diagram. ............................................................... 14
Figure 8: RIN Credit Value Structure and Logic Diagram. .......................................................... 15
Figure 9: Renewable Electricity Production Value Structure and Logic Diagram ....................... 16
Figure 10: Renewable Natural Gas Value Structure and Logic Diagram .................................... 17
Figure 11: GHG Emissions Structure and Logic Diagram. ......................................................... 23
ii
Tables
Table ES-1: Summary and Ranking of Monetary and Non-Monetary Results .............................. 3
Table ES-2: Indexed and Weighted Scores for each Alternative .................................................. 4
Table ES-3: Potential Biogas Utilization Alternatives Combinations ............................................. 5
Table 1: Summary of the Alternatives and Diversion Scenarios evaluated for Feasibility .......... 11
Table 2: Biogas Utilization Alternatives Summary ...................................................................... 13
Table 3: Value of RIN Credits ..................................................................................................... 15
Table 4: Value of Renewable Electricity Production ................................................................... 16
Table 5: Estimated Energy Inputs for Each Alternative .............................................................. 19
Table 6: Estimated GHG Emissions ........................................................................................... 22
Table 7: Social Costs of GHG Emissions ................................................................................... 23
Table 8: Summary of Monetary Benefits and Costs ($ Millions, 2019) ....................................... 24
Table 9: Summary of Non-Monetary Impacts ............................................................................. 25
Table 10: Summary and Ranking of Monetary and Non-Monetary Results ................................ 26
Table 11: Indexed and Weighted Scores for each Alternative .................................................... 27
Table 12: Potential Biogas Utilization Alternatives Combinations ............................................... 28
Appendices
Appendix A - Low Diversion Scenario Digester Costs
Appendix B – Financial Proforma – Breakeven Analysis
City of Iowa City | CAAP Methane Recovery Feasibility Study
Executive Summary
ES-1
Executive Summary
In December 2019, the City of Iowa City (City) selected HDR Engineering, Inc. (HDR) to perform
a Methane Recovery Feasibility Study to address two specific Action Items included in the Iowa
City Climate Action and Adaptation Plan (CAAP):
Action Number 3.7: Take Action on a Study to Efficiently Capture and Use Methane
from Wastewater Operations
“After water is used by residents, it flows into the wastewater system and then goes to the
City’s Wastewater Treatment Facility. While the City currently captures methane gas from
the digesters used in the wastewater treatment process, only a portion of the methane is
used to offset natural gas usage for the plant. To explore other options for further
management of wastewater greenhouse gas (GHG) emissions, the City should conduct a
study to determine the feasibility of using all captured methane to create renewable fuel
or electricity that can be used to operate the facility, and take specific actions based on
the results of this study.”
Action Number 3.8: Take Action on a Feasibility Study on Energy Generation from
Landfill Methane
“The methane produced by decomposition of organic waste in the Iowa City Landfill is
currently being flared to transform it into carbon dioxide, which is a less potent GHG. The
City has been considering methods to use the methane as a renewable energy source,
and to further explore this opportunity, the City will conduct a Feasibility Study in FY2019
and take specific actions based on the results of this study.”
This Feasibility Report incorporates a number of recently completed Technical Memorandums
(TMs) that evaluated current and future biogas generation potential and identified alternatives for
utilizing biogas at the Iowa City Wastewater Treatment Plant (WWTP) and/or the Landfill and
Recycling Center (Landfill). HDR used its Sustainable Return on Investment (SROI) process to
measure the feasibility of the objectives.
The Study objectives are to evaluate current and future methane generation, collection,
processing, and reuses at the two facilities based on the following three categories for feasibility:
• Net GHG emissions, considering both incremental emission sources and direct and
indirect reductions;
• Net Energy impacting, applying an Energy Return on Energy Invested (EROEI)
methodology;
• Economics, using HDR’s SROI framework to monetize the benefits associated with
beneficial reuse of methane sourced from the Landfill and WWTP.
HDR analyzed three alternatives to beneficially reuse biogas generated at the WWTP and Landfill,
as well as GHG emissions and financial impact of expanding composting operations to handle
City of Iowa City | CAAP Methane Recovery Feasibility Study
Executive Summary
ES-2
incremental food waste diverted from the Landfill. The following is a description of each
alternative:
• Alternative 1: Natural Gas Pipeline Injection. This alternative is divided into two sub-
alternatives:
o Alternative 1a – WWTP NG Pipeline Injection.
o Alternative 1b – Landfill NG Pipeline Injection.
• Alternative 2: Electricity Generation. This alternative is divided into two sub-
alternatives:
o Alternative 2a – WWTP Electricity Generation.
o Alternative 2b – Landfill Electricity Generation.
• Alternative 3: WWTP Natural Gas Replacement
• Alternative 4: Composting
Recognizing the synergy with another Action in the City’s CAAP, Item 3.2 Increase Composting
of Organics, the alternatives consider impacts of diverting incremental volumes of food waste
from the Landfill to the existing WWTP, a new, dedicated anaerobic digester (AD) located at the
WWTP, and expanded composting operations. Each of the alternatives listed except Alternative
No. 4 consider three organics diversion scenarios:
1) No incremental organics diversion (No-Diversion)
2) Additional 1,500 tons organics diverted from Landfill, which represents the available
capacity at the existing WWTP AD (1,500 tons)
3) 20% of food waste diverted from landfill to a future “new” AD (Low-Diversion)
HDR developed an opinion of probable construction costs (OPCC) and opinion of operations and
maintenance (O&M) costs for the No-Diversion scenario for each alternative. The No-Diversion
scenario costs were then extrapolated to estimate costs for the two diversion scenarios for each
alternative.
The SROI analysis considers the triple bottom line (i.e., economic, environmental, and social)
benefits of methane reuse. This study focuses on the economic and environmental impacts.
The analysis took into account:
• Estimated reductions in GHG emissions and the associated social cost of carbon;
• Value of Renewable Identification Number (RIN) credits under the Renewable Fuel
Standard Program;
• Value of electricity exported to the grid under net metering and buyback agreements with
MidAmerican Energy Company and the Eastern Iowa Light and Power Cooperative;
• Value of avoided natural gas purchases;
• Capital investment and O&M costs of biogas reuse alternatives; and
• Energy Return on Investment (EROEI).
The results of this study are intended to help the City assess the viability of, and prioritize,
alternatives with the greatest potential to reduce GHG emissions under CAAP Action Items 3.7
City of Iowa City | CAAP Methane Recovery Feasibility Study
Executive Summary
ES-3
and 3.8. This Report details technical information on the feasibility analysis and summarizes the
previous Technical Memorandums (TMs) that were completed by HDR leading up to the SROI
analysis:
1. Evaluation of Existing Facilities TM
2. Wasteshed Analysis TM
3. Biogas Utilization Alternatives TM
The monetary and non-monetary results and rankings by metric are presented in Table ES-1. The
evaluation of economic and environmental impacts considered a time horizon or study period,
which includes project development (construction and implementation) and 30 years of operation
and benefit. This extends to 2050 and aligns with the planning horizon of the City’s CAAP. All
monetary Costs and benefits have been converted to present value using a 3% discount factor
and are compared using a benefit to cost ratio (BCR), benefits divided by costs. BCR’s exceeding
1.0 indicate that the benefits from the alternative exceed the costs of the inv estment over a 30
year period. The non-monetary metrics include EROEI and lifecycle change in CO2e emissions.
Table ES-1: Summary and Ranking of Monetary and Non-Monetary Results
Alternative
Description
Location Alternative GHG
Reduction
GHG
Rank
EROEI EROEI
Rank
BCR BCR
Rank
Pipeline
Injection
WWTP Alt. 1a - ND 40,500 15 6.9 9 0.20 11
Alt. 1a - 1500 77,800 12 7.9 6 0.22 9
Alt. 1a - LD 436,200 6 7.9 4 0.39 8
Landfill Alt. 1b - ND 820,500 3 7.5 8 1.62 3
Alt. 1b - 1500 844,500 2 7.6 7 1.63 2
Alt. 1b - LD 931,800 1 7.9 5 1.69 1
Electricity
Generation
WWTP Alt. 2a - ND 19,000 16 2.0 13 0.05 16
Alt. 2a - 1500 60,000 13 12.4 3 0.10 15
Alt. 2a - LD 395,600 7 13.3 1 0.18 12
Landfill Alt. 2b - ND 459,200 5 1.5 15 0.76 6
Alt. 2b - 1500 386,500 8 2.1 12 0.69 7
Alt. 2b - LD 585,200 4 12.6 2 0.89 5
Natural Gas
Replacement
WWTP Alt. 3 - ND 40,900 14 4.6 10 0.11 14
Alt. 3 - 1500 78,300 11 3.4 11 0.13 13
Alt. 3 - LD 252,200 10 1.8 14 0.20 10
Expanded
Composting
Compost Alt. 4 365,100 9 0.0 16 0.96 4
The results show that:
• Only Alternative 1b (landfill natural gas) has benefits that exceed the costs;
• The highest BCR (1.69) is Alternative 1b – Low-Diversion. This alternative ranks highest
on total lifecycle CO2e emission reductions, and when combined with the value of RIN
credits results in the greatest economic benefits;
• All of the alternatives result in a net reduction in CO2e over the next 30 years;
City of Iowa City | CAAP Methane Recovery Feasibility Study
Executive Summary
ES-4
• All alternatives except for composting result in an EROEI of 1.0 or greater (incremental
composting of food waste does not generate energy);
• Alternative 2a (WWTP Electricity Generation) – Low-Diversion ranks highest on EROEI;
• Alternative 1b – Low-Diversion is ranked 5th on EROEI; and
• Changing the value of the SCC was found to have no effect in ranking as the value
influences all of the alternatives equally.
To aid in the comparison of the monetary and non-monetary metrics and provide insight from this
Feasibility Study towards actions under 3.7 and 3.8, the results have been combined into a
weighted score as shown below in Table ES-2. Each result was converted to an index (1 to 0)
and were then weighted equally into a total score with a maximum value of 1.
Table ES-2: Indexed and Weighted Scores for each Alternative
Alternative
Description
Location Alternative GHG
Reduction
EROEI BCR Total
Score
Rank
Pipeline
Injection
WWTP Alt. 1a - ND 0.01 0.17 0.04 0.23 13
Alt. 1a - 1500 0.03 0.20 0.04 0.27 11
Alt. 1a - LD 0.16 0.20 0.08 0.43 6
Landfill Alt. 1b - ND 0.29 0.19 0.32 0.80 3
Alt. 1b - 1500 0.30 0.19 0.32 0.81 2
Alt. 1b - LD 0.33 0.20 0.33 0.86 1
Electricity
Generation
WWTP Alt. 2a - ND 0.01 0.05 0.01 0.07 16
Alt. 2a - 1500 0.02 0.31 0.02 0.35 7
Alt. 2a - LD 0.14 0.33 0.04 0.51 5
Landfill Alt. 2b - ND 0.16 0.04 0.15 0.35 8
Alt. 2b - 1500 0.14 0.05 0.14 0.33 9
Alt. 2b - LD 0.21 0.32 0.18 0.70 4
Natural Gas
Replacement
WWTP Alt. 3 - ND 0.01 0.12 0.02 0.15 14
Alt. 3 - 1500 0.03 0.08 0.02 0.14 15
Alt. 3 - LD 0.14 0.05 0.04 0.23 12
Expanded
Composting
Compost Alt. 4
0.13 0.00 0.19 0.32 10
Based on the indexing and weighting exercise:
• Alternative 1b (landfill natural gas) – Low-Diversion has the highest score (0.86).
• Alternative 1b (landfill natural gas) – 1500 ton diversion is ranked second.
• Alternative 1b (landfill natural gas) – No-Diversion is ranked third.
If the City is instead focused on reductions that will be reflected in its municipal and community -
scale GHG emission inventory, then evaluation should be narrowed to focus on Alternative 2,
Electricity Generation, and Alternative 3, Natural Gas Replacement. While electricity generated
at the WWTP or Landfill (2a and 2b, respectively) could very well be pushed to the power grid,
contractual agreements with local utilities could allow the City to retain and retire RECs for GHG
accounting purposes. Specifically, RECs could be applied to the City’s Scope 2 market -based
GHG inventory. Using RNG to displace natural gas use at the WWTP would result in lower
City of Iowa City | CAAP Methane Recovery Feasibility Study
Executive Summary
ES-5
Scope 1 GHG emissions. Focused on these two alternatives, Alternative 2b – Low-Diversion is
ranked highest (fourth overall), followed by Alternatives 2a – Low-Diversion and 2a – 1500. These
alternatives are ranked 4, 5 and 7 overall.
Finally, biogas utilization alternatives can be combined together with others, and some can be
incorporated as standalone projects (as shown in Table ES-3).
Table ES-3: Potential Biogas Utilization Alternatives Combinations
There are 18 unique possible combinations of alternatives, boxes in Table ES-3 with blue
numbering indicate the individual alternative scenarios at either the Landfill or at the WWTP. The
individual alternatives can be combined together, but must be done so following the same waste
diversion scenario from the Landfill. Specifically, an alternative from No-Diversion scenario cannot
be combined with an alternative from the Low-Diversion scenario. When combining the
alternatives the scores from the Landfill and WWTP alternatives can be added together to identify
the optimal combination of actions under each of the waste diversion scenarios. The highest
scored individual alternatives are consistently Alternative 1b – NG Pipeline Injection (landfill
alternatives for each of the No-Diversion, 1500 ton diversion, and Low-Diversion scenarios).
Identifying the optimal combination of actions may be approached as follows: select the highest
scored alternative from the desired waste diversion scenario (shown to be from the Alternative 1b
– NG Pipeline Injection landfill alternatives) then work down the column to the corresponding
green shaded boxes. Select the highest scored, or desired, combination. Corresponding capital
costs for each individual alternative are also additive when combined. For example, if choosing
NG Pipeline
Injection
Electricity
Generation
NG Pipeline
Injection
Electricity
Generation
NG Pipeline
Injection
Electricity
Generation
Alt 1b-ND Alt 2b-ND Alt 1b-1500 Alt 2b-1500 Alt 1b-LD Alt 2b-LD
0 0.80 0.35 0.81 0.33 0.86 0.70
NG Pipeline
Injection Alt 1a-ND 0.23 1.02 0.58
Electricity
Generation Alt 2a-ND 0.07 0.87 0.42
NG
Replacement Alt 3-ND 0.15 0.95 0.50
NG Pipeline
Injection Alt 1a-1500 0.27 1.08 0.60
Electricity
Generation Alt 2a-1500 0.35 1.16 0.68
NG
Replacement Alt 3-1500 0.14 0.95 0.47
NG Pipeline
Injection Alt 1a-LD 0.43 1.30 1.13
Electricity
Generation Alt 2a-LD 0.51 1.37 1.21
NG
Replacement Alt 3-LD 0.23 1.09 0.93WWTP LocationLandfill Location
Low Diversion1500 ton/yr DiversionNo Diversion 1500 ton/yr Diversion Low Diversion
Do Nothing
Weighted and Indexed Performance
Indicators
Total Score, inclusive of:
GHG Reduction, EROI, and BCR
Do Nothing
No Diversion
City of Iowa City | CAAP Methane Recovery Feasibility Study
Executive Summary
ES-6
from Alternative 1b – NG Pipeline Injection (at the Landfill, Total Score of 0.81), with 1500 ton
diversion to the WWTP, work down the column (or “diversion lane”) to the desired combination
scenario. In this case, combining with Alternative 2a – Electricity Generation at the WWTP, results
in a combined score of 1.16. As capital costs are also additive, consideration should be given to
the seemingly minor weighted score differential. In the example of combined Alt 1b-1500 with Alt
2a-1500, there is an estimated $6.2M savings to select Alt 1b-1500 with Alt 1a-1500.
Path Forward
HDR recognizes that incremental food waste diversion is not an instantaneous process, but the
SROI analysis provides an assessment of the resulting impact when achieved. This Report
provides decision tools to support the City’s further consideration and decision making.
Consequently, the City might consider the following path forward to further evaluate and
implement the preferred alternative(s):
i. City decision on desired diversion scenario and methane utilization at the WWTP to
narrow the field of alternatives. (0-6 months)
ii. Further technical analysis to develop organics management strategies to achieve a
targeted diversion scenario and further evaluate life cycle costs of co-digestion (if desired)
and biogas utilization to generate electricity or RNG. Consideration of impacts to planned
digester rehab project. (3-6 months)
iii. Conceptual Design Development of the selected alternative(s), providing basis of design
parameters and implementation planning. (3-6 months)
iv. Detailed Design Development. (TBD)
v. Bidding and Construction. (TBD)
It may be prudent for the City to complete items i) and ii) within the next 6-months for capital
planning purposes.
City of Iowa City | CAAP Methane Recovery Feasibility Study
Introduction
1
1 Introduction
In December 2019, the City of Iowa City (City) selected HDR Engineering, Inc. (HDR) to perform
a Methane Recovery Feasibility Study to address Action Items 3.7 and 3.8 included in the Iowa
City Climate Action and Adaptation Plan (CAAP). The CAAP contains objectives for conducting a
study that would determine the feasibility of methane generation, collection, processing, and
potential re-use at the Iowa City Wastewater Treatment Plant (WWTP) and/or the Landfill and
Recycling Center (Landfill). HDR used its Sustainable Return on Investment (SROI) process to
measure the feasibility of the objectives.
This Feasibility Report evaluates alternatives for methane gas recovery and beneficial reuse of
biogas at the City WWTP and/or Landfill as part of the City’s CAAP objectives. This evaluation
focuses on monetizing the benefits associated with the reuse of methane sourced from either the
WWTP and/or the Landfill. The SROI analysis considers the triple bottom line (i.e., economic,
environmental, and social) benefits of methane reuse. This study focuses on the economic and
environmental impacts.
The analysis took into account:
• Estimated reductions in Greenhouse Gas (GHG) emissions and the associated social cost
of carbon;
• Value of Renewable Identification Number (RIN) credits under the Renewable Fuel
Standard Program (RFS);
• Value of electricity exported to the grid under net metering and buyback agreements with
MidAmerican Energy Company and the Eastern Iowa Light and Power Cooperative;
• Value of avoided natural gas purchases;
• Capital investment and O&M costs of biogas reuse alternatives; and
• Energy Return on Investment (EROEI).
The results of this Study are intended to help the City assess the viability of alternatives with the
greatest potential to reduce GHG emissions under CAAP Action Items 3.7 and 3.8. This Report
details technical information on the feasibility analysis and summarizes the previous Technical
Memorandums (TMs) that were completed by HDR leading up to the SROI analysis:
1. Evaluation of Existing Facilities TM
2. Wasteshed Analysis TM
3. Biogas Utilization Alternatives TM
2 Project Background
2.1 Climate Action and Adaptation Plan
In September of 2018, the City Council approved its Climate Action and Adaptation Plan. CAAP
included specific actions to achieve GHG emissions targets. The plan’s targets are in accordance
with the Paris Agreement and include city-wide carbon emissions reductions of 25-28% over 2005
City of Iowa City | CAAP Methane Recovery Feasibility Study
Project Background
2
levels. On August 6th, 2019, the City passed Resolution 19-218 declaring a climate crisis and
requesting accelerated action toward carbon emissions reductions in an effort to meet the
Intergovernmental Panel on Climate Change (IPCC) target of limiting global warming to 1.5
Celsius.
CAAP identified 35 actions related to buildings, transportation, waste, adaptation, and sustainable
lifestyle to help the City achieve its goals for reducing carbon emissions. Furthermore, th ese 35
actions were broken into 3 phases with phase 1 actions to be initiated by the end of 2020. Under
waste actions 3.7 and 3.8 the City is looking to explore ways to recover and beneficially reuse
methane from landfill and WWTP. The importance of these actions were reiterated in the
Accelerating Iowa City’s Climate Action Plan, published in April 2020. As noted in the CAAP:
Action Number 3.7: Take action on a feasibility study to efficiently capture and use
methane from wastewater operations:
“After water is used by residents, it flows into the wastewater system and then goes to the
City’s Wastewater Treatment Facility. While the City currently captures methane gas from
the digesters used in the wastewater treatment process, only a portion of the methane is
used to offset natural gas usage for the plant. To explore other options for further
management of wastewater greenhouse gas (GHG) emissions, the City should conduct a
study to determine the feasibility of using all captured methane to create renewable fuel
or electricity that can be used to operate the facility, and take specific actions based on
the results of this study.”
Action Number 3.8: Take action on a feasibility study on energy generation from
landfill methane.
“The methane produced by decomposition of organic waste in the Iowa City Landfill is
currently being flared to transform it into carbon dioxide, which is a less potent GHG. The
City has been considering methods to use the methane as a renewable energy source,
and to further explore this opportunity, the City will conduct a feasibility study in FY2019
and take specific actions based on the results of this study.”
2.2 Feasibility Study
The objective of this Feasibility Study is to evaluate alternatives developed to support actions 3.7
and 3.8. To conduct this study, HDR applied its SROI framework to evaluate alternatives. The
following sections of this report detail:
• The approach used.
• The alternatives considered.
• The economic analysis methods used to evaluate alternatives.
• A summary of the economic analysis results.
• Recommendations for waste actions 3.7 and 3.8.
City of Iowa City | CAAP Methane Recovery Feasibility Study
Project Background
3
2.2.1 SROI Background
SROI evaluates whether the public value of a project is sufficient to justify the money required to
develop the project and which alternative provides the greatest financial and societal return
relative to the project cost. SROI process is an enhanced form of benefit cost analysis (BCA) that
involves a systematic comparison of the benefits and costs of projects in ways that communicate
a project’s triple-bottom line outcomes, (i.e. its full range of environmental, social and economic
impacts). SROI originated from a commitment by HDR to develop a new generation of public
decision support metrics for the Clinton Global Initiative (CGI) in 2007. SROI was developed with
input from Columbia University’s Graduate School of International Public Affairs and launched at
the 2009 CGI annual meeting. Since then, the SROI process has been used by HDR to evaluate
the monetary value of numerous sustainability programs and projects for water and wastewater
infrastructure utilities around the country.
2.2.2 Methodology of SROI Process
The SROI process draws from standard economic BCA methods and the best available data to
systematically calculate and compare the benefits and costs of project alternatives. The process
addresses sustainability goals and outcomes from a triple bottom-line perspective, meaning the
range of potential environmental, social, and economic impacts (see Figure 1). In this Feasibility
Study, impacts are associated with the economic and environmental benefits related to the value
of RIN credits to the City as well as the social cost of carbon associated with changes in GHG
emissions. In addition, the EROEI and tons of GHG emissions are estimated as non-monetary
metrics.
Figure 1: SROI Triple Bottom Line Accounting
The SROI process builds on best practices in benefit-cost and financial analysis methodologies,
complemented by advanced risk analysis and stakeholder elicitation. Typically, the SROI process
is implemented in four steps, which include:
1. Develop the structure and logic diagrams (S&L’s): Structure and logic diagrams are
useful to display the understanding of how key variables within an analysis interact to
influence the intermediate or final outputs being measured. These diagrams provide a
City of Iowa City | CAAP Methane Recovery Feasibility Study
Renewable Natural Gas as a Resource
4
transparent view of the calculations being made in the analyses for key stakeholders and
subject matter experts to review and understand the process better.
2. Assign values to inputs: Values are assigned to inputs based on logic established in the
S&L’s. In some instances, ranges for inputs are established to enable the analysis to
capture how an input will impact the project with the potential variability of its value
essentially simulating real world conditions.
3. Develop consensus among stakeholders to validate inputs: The S&L’s and inputs are
then presented to stakeholders for validation. This is a key step in the SROI process.
Stakeholders and subject matter experts are consulted regarding the values used to
understand their view on these inputs. This step is critical for getting stakeholder buy-in
on the process and seeking out additional knowledge that may not have been captured
previously.
4. Evaluate impact on agency goals (e.g. cost, environmental impact, public
perception, etc.), including simulation if applicable: These inputs will then be added
into the model structure detailed with the structure and logic diagrams to evaluate the
agency goals, specifically the costs or environmental impact. The alternative that best
meets these criteria will be the one that is the most desirable alternative.
3 Renewable Natural Gas as a Resource
Renewable Natural Gas (RNG) is biogas or landfill gas that has been treated or refined to natural
gas (NG) quality. The resulting RNG can be used interchangeably with NG, but is considered
renewable as it doesn’t rely on petroleum and can therefore provide additional environmental
attributes through federal and state programs.
3.1 Renewable Natural Gas - Environmental Attributes as Vehicle
Fuel
3.1.1 EPA - Renewable Fuel Standard
The United States Congress created the Renewable Fuels Standard (RFS) through the Energy
Policy Act of 2005 and revised the program with the Energy Independence and Security Act in
2007. The RFS is a renewable fuels program within the Clean Air Act which mandates that large
fuel producers and blenders (Obligated Parties) must include within their fuel mix a growing
portion of renewable fuels. The quotas required of the Obligated Parties are referred to as
Renewable Volume Obligations (RVOs) and are established and tracked by the United States
Environmental Protection Agency (EPA) through the use of renewable credits, also known as,
Renewable Identification Numbers (RINs). The original program was designed to increase the
RVOs until 2022 and then level off beyond that point unless Congress issued another
amendment. The EPA can lower or raise the RVOs up to the maximum RVO quota set for 2022,
but Congressional action would be required to eliminate the RFS program. The RFS program has
pressure against it from the Oil and Gas Industry, but also has a strong support from the Corn
Ethanol Industry, who represent half of the RIN market.
City of Iowa City | CAAP Methane Recovery Feasibility Study
Renewable Natural Gas as a Resource
5
As the EPA’s RFS, RVOs are developed by categorized RIN types based on their environmental
benefit and the production pathway. These categories, D3 through D7, encompass lower value
biofuels like corn-based ethanol (D6) up to high value biofuels like cellulosic biodiesel or ethanol
(D3) (see Figure 2).
RNG produced from landfill gas is considered D3 cellulosic biofuel in the RFS. RNG produced
from wastewater biogas production from anaerobic digestion or co-digestion is considered D3
cellulosic or D5 advanced biofuel depending on the feedstocks used to production. The biogas
produced from the digestion of municipal biosolids will be considered D3 cellulosic and have the
highest value. However, any biogas produced by the co-digestion of municipal solids with hauled
in or high strength wastes will be considered D5 advanced, unless each individual feedstock has
a 75% or higher cellulosic content.
Figure 2: EPA RFS Nested RIN Categories and Volumes
Figure 3 presents the historical RIN values as reported by the EPA from 2015 through August
2020.
City of Iowa City | CAAP Methane Recovery Feasibility Study
Renewable Natural Gas as a Resource
6
Figure 3: Historical RIN values From the EPA from 2015 Through August 2020
Source: https://www.epa.gov/fuels-registration-reporting-and-compliance-help/rin-trades-and-price-information
3.1.2 California Low Carbon Fuel Standard
In addition to RINs, carbon offset credits are also available through California’s Low Carbon Fuel
Standard (LCFS) program. The LCFS market has become a healthy market with more
transactions and higher values throughout the last seven years (see Figure 4) and is not
anticipated to end until 2032. LCFS credits can be obtained in addition to RIN credits as long as
the renewable fuel is contracted for sale to an Obligated Party with end use in California.
City of Iowa City | CAAP Methane Recovery Feasibility Study
Renewable Natural Gas as a Resource
7
Figure 4: California LCFS Market History
3.1.3 Requirements and Pathways
A requirement to be aware of for both of these programs (RFS and LCFS) is that they are
specifically renewable fuels for transportation programs. As such, the fuel must ultimately be used
as a transportation fuel in order for the renewable attribute to be recognized. A renewable fuel
producer is not required to explicitly find a transportation end user of the fuel it produces, however,
at some point along the fuel supply pathway, it must be used as transportation fuel so that an
Obligated Party can claim the RIN and/or the LCFS credit and meet its obligation with the EPA or
with California.
The production and sale of RNG and environmental attributes like RINs and/or LCFS occurs in
two pathways; the physical pathway and the contractual pathway for the attributes. The physical
pathway is the sale of the RNG by the producer to end user of the gas via the natural gas grid.
The contractual pathway for the attributes is separate and handled by third party which verifies
that the RNG is truly renewable and markets the attributes to Obligated Parties. Figure 5 illustrates
the two pathways of RNG and RIN/LCFS sales. It is important to note that the molecules of natural
gas don’t actually have to be used as vehicle fuel, but the physical pathway needs to be verified
through the grid system.
City of Iowa City | CAAP Methane Recovery Feasibility Study
Renewable Natural Gas as a Resource
8
Figure 5: PhysRNG Value Considerations
The value of RNG should take into account following:
1. The value of the RNG as natural gas based on the natural gas commodity market.
2. The value of environmental attributes obtained through the RFS (D3 or D5)
3. The value environmental attributes obtained through the LCFS.
4. The cost of compliance with the RFS and LCFS.
5. The cost of marketing the environmental attributes to Obligated Parties.
Items 1-3 should be considered as ranges (low, median, high) to account for the variability in
future market values. The biogas revenues at the WWTP need to be divided into D3 and D5
categories. The biogas produced in the anaerobic digesters handling municipal biosolids will
produce D3, but biogas produced at the co-digestion facility will be D5, but may be eligible for
LCFS depending on the carbon intensity score. Items 4 and 5 are included to reflect the cost of
bringing the gas to market within the environmental attribute programs. The RFS is highly
regulated, so market RIN values are typically reduced by 15% and the LCFS values by 15-30%
to account for the third part cost of compliance and marketing the environmental attributes to
Obligated Parties. The third parties are either gas marketing companies or the Obligated Parties
themselves, and are typically selected by a Request for Proposal (RFP) process. The resulting
contractual arrangement specifies the City’s share be based on either a fixed price or percentage
of total revenue and the term of the agreement. The third party will qualify the RINs with EPA,
qualify with California for LCFS credits, develop QA programs for certification, and administer the
program. The City is then paid by the third party for both the natural gas commodity value and the
associated renewable attributes based on a monthly or quarterly invoice.
City of Iowa City | CAAP Methane Recovery Feasibility Study
Description of Project Alternatives
9
4 Description of Project Alternatives
Three beneficial reuse alternatives were analyzed for current and future biogas generated at the
WWTP and Landfill. For a complete and detailed assessment, please refer to the Biogas
Utilization Alternatives Analysis Technical Memorandum previously provided by HDR, dated July
17, 2020. Recognizing synergy with another action in the City’s CAAP, Action Item 3.2 Increase
Composting of Organics, HDR also considered impacts of diverting incremental volumes of food
waste from the Landfill to the existing WWTP, a new, dedicated anaerobic digester, and expanded
composting operations. The following is a description of each alternative.
4.1 Alternative 1: Natural Gas Pipeline Injection
Biogas Utilization Alternative 1 assumes that the City purchases and operates equipment to
condition the biogas to natural gas quality (RNG) for injection into the natural gas pipeline. To
provide an interconnection point, the natural gas utility (MidAmerican Energy Company) would
route a new pipeline from the existing natural gas distribution system to the City’s property. The
City would be required to reimburse the utility for the cost of the connecting pipe, and also pay an
annual pipeline usage fee. This pipeline usage fee is dependent on the amount of RNG injected
into the natural gas pipeline by the City. Assuming natural gas quality meets the RFS Program,
the City would sell RIN credits and surrender any downstream GHG emissions reductions that
would be realized by the Obligated Party purchasing the credits. Alternative 1 is applicable to both
the WWTP and Landfill, presented as alternatives 1a and 1b, respectively.
4.2 Alternative 2: Electricity Generation
Biogas Utilization Alternative 2 assumes that biogas is conditioned and utilized in engine
generators owned and operated by the City to produce renewable electricity. The electric power
utility (MidAmerican Energy or Eastern Iowa Light & Power) would establish a connection to the
grid, enabling the City to sell the renewable power. The City would be required to reimburse the
electric utility for all system upgrades required to accommodate the connection. Under this
alternative, HDR assumes that the City’s contract with the electric power utility would allow the
City to retain Renewable Energy Credits (RECs) to offset GHG emission associated with
electricity use in their buildings and facilities. Alternative 2 is applicable to both the WWTP and
Landfill, presented as alternatives 2a and 2b, respectively.
4.3 Alternative 3: WWTP Natural Gas Replacement
Biogas Utilization Alternative 3 involves conditioning biogas to natural gas quality with the intent
of using the RNG in place of the natural gas at the WWTP. Biogas would be conditioned to natural
gas quality by equipment owned and operated by the City to be installed at the WWTP. The
WWTP RNG produced will exceed the amount of natural gas used at the plant. As such, the City
would need to either: find a use for the excess RNG produced, flare the excess gas, or the City
would only condition the amount of biogas needed and the excess biogas would be flared. For
this analysis, it was assumed that RNG production would be capped at 62,848 standard cubic
feet per day. Alternative 3 is only applicable to the WWTP as natural gas is not consumed at the
landfill.
City of Iowa City | CAAP Methane Recovery Feasibility Study
Description of Project Alternatives
10
4.4 Alternative 4: Composting
Alternative 4 consists of diverting organic waste that would typically be placed in the landfill to a
new or expanded composting facility. Because the existing composting operation is at capacity,
this alternative assumes the City would utilize existing owned-land and purchase equipment to
expand composting capacity. This alternative is only relevant for the Low-Diversion scenario,
further described in the section below.
4.5 Organics Diversion Scenarios
Recognizing the synergy with the City’s goal to increase composting of organics, HDR evaluated
the relative cost and GHG emissions impact for each of the four alternatives under three food
waste diversion scenarios. HDR’s previous technical analysis determined the impact on future
biogas generation quantity when some of the City’s organic matter is diverted from the Landfill for
co-digestion or composting.
The three organics diversion scenarios include:
1) No Organics Diversion. The No Organics Diversion scenario assumes that all organics
material is disposed of in the Landfill (i.e. current operation).
2) 1,500 tons. The 1,500 tons scenario assumes that an additional 1,500 tons of food waste
material will be diverted from the Landfill to the existing WWTP anaerobic digester each
year. This quantity represents the current available capacity in the WWTP anaerobic
digester; therefore, no additional digester capacity is required for this diversion scenario.
This scenario is not applicable to composting, as the existing facility is operating at
capacity.
3) Low-Diversion. The Low-Diversion scenario assumes that 20% of organic material (7,960
tons/year) currently disposed of at the Landfill is diverted to new anaerobic digesters or
an expanded composting facility. For GHG emissions modeling purposes, HDR assumed
that the additional diverted organic material is entirely comprised of food waste. The
required anaerobic digester volume required for the Low-Diversion scenario is 1.4 million
gallons (MG).
For purposes of this study, HDR assumed that the new waste receiving station and standalone
anaerobic digesters required to accept the additional diverted food waste would be located at the
WWTP. A standalone digester facility for the diverted organic waste was assumed because the
RIN credits for RNG produced in a municipal WWTP digester will have a higher value than those
for RNG produced by a diverted waste digester. Additionally, the WWTP digester gas con tains
high levels of siloxanes. It is beneficial to keep the two sources of biogas separated until the
siloxanes are removed from the WWTP biogas. Over the course of the Study development,
discussion with City staff supported retaining digester capacity within the existing complex to
support municipal biosolids. Therefore, for a planning level, Feasibility Study, an independent
system to support new low-diversion digesters is proposed. Implementation would include
independent operation, and not an expansion of the existing digester facility. However, as the
plan is refined, a more detailed evaluation and conceptual design should be conducted to further
determine the best approach for the City.
City of Iowa City | CAAP Methane Recovery Feasibility Study
Description of Project Alternatives
11
Figure 6: Organics Diversion
A summary of the alternatives and diversion scenarios selected for the SROI analysis are listed
in Table 1.
Table 1: Summary of the Alternatives and Diversion Scenarios evaluated for Feasibility
Alternative Description Facility
Location
Scenario Name
Pipeline Injection
(Alt. 1)
Sell RIN credits, & no additional organics
diversion
WWTP Alt. 1a - ND
Landfill Alt. 1b - ND
Sell RIN credits, & 1,500 TPY organics
diverted from landfill
WWTP Alt. 1a - 1500 Div
Landfill Alt. 1b - 1500 Div
New AD facility, sell RIN credits, & 7,960
TPY organics diverted from landfill
WWTP Alt. 1a - LD
Landfill Alt. 1b - LD
Electricity
Generation
(Alt. 2)
No additional organics diversion WWTP Alt. 2a - ND
Landfill Alt. 2b - ND
1,500 TPY organics diverted from landfill WWTP Alt. 2a - 1500 Div
Landfill Alt. 2b - 1500 Div
7,960 TPY organics diverted from landfill WWTP Alt. 2a - LD
Landfill Alt. 2b - LD
Natural Gas
Replacement
(Alt. 3)
No additional organics diversion WWTP Alt. 3 - ND
1,500 TPY organics diverted from landfill WWTP Alt. 3 - 1500 Div
New AD facility, & 7,960 TPY organics
diverted from landfill
WWTP Alt. 3 - LD
Expanded Composting
(Alt. 4)
7,960 TPY organics diverted from landfill Compost Alt. 4
Some of the alternatives listed in Table 1 can be constructed as standalone alternatives.
Additionally the alternatives can be constructed together in various combinations provided the
same waste diversion scenario is followed. For example, Alternative 1b – NG Pipeline Injection
at the Landfill may be constructed at the Landfill with no improvements at the WWTP.
City of Iowa City | CAAP Methane Recovery Feasibility Study
Description of Project Alternatives
12
Alternatively, Alternative 1b could be selected for utilization of the biogas at the Landfill, with
Alternative 2a (Electricity Generation) selected for biogas utilization at the WWTP.
A more detailed explanation and associated matrix table of possible combination scenarios is
included later under Section 5.1.
4.5.1 Impacts to Existing Wastewater Treatment Plant
Implementation of anaerobic digestion for organics diversion can result in impacts to the existing
WWTP. The diverted organics need to be incorporated into a mixture with a target feed total solids
(TS) content of 6 percent. This requires the use of makeup water to create th e mixture in a
receiving station. Typically, the makeup water is a combination of digester recycle and WWTP
effluent. The total water feed rate into the digester is estimated near 90,000 gallons per day, and
the makeup water stream would be small.
A more important impact to the existing WWTP is the return stream from the diversion digester.
After dewatering of the digested solids, some of the excess water must be returned to the plant
as recycle. Digestion of organics results in the release of nutrients, ni trogen and phosphorus in
the forms of ammonium and phosphate, respectively. After dewatering, the nutrients are divided
between the solids and liquids residuals. A fraction of the nutrients would remain with the solids
to their ultimate disposal (e.g. land application or landfilling). The remaining fraction is recycled
with the liquid residuals to the WWTP. Recycled nutrients then consume part of the nitrification
and nutrient removal capacities of the treatment facility. In addition, the carbon to nutrient ratio is
skewed and biological nutrient removal becomes less favorable. This means that carbon addition
may be needed to support biological nutrient removal. Further, liquid treatment capacity and cost
must be reevaluated with potential increases to nutrient loading.
Organic waste nutrient content varies considerably. The nitrogen content can vary between 5 and
50 percent of the TS, and the phosphorus content can vary between 1 and 10 percent of the TS.
This analysis used typical food waste values of roughly 10 percent for nitrogen content and 5
percent for phosphorus for the analysis. The result is an additional 150 to 200 lb-N/d nitrogen load
and an additional 30 to 50 lb-P/d phosphorus load estimated for the WWTP for every ton/d of
organics diversion. In all, every 1 ton/d of diverted wastes results in a recycle containing between
2 and 3 percent of the WWTP’s nitrogen capacity. The Low-Diversion scenario is based on about
4 ton/d of organics diversion, which could use between 8 and 12 percent of the WWTP’s TKN
capacity1.
4.6 Estimated Costs
A detailed opinion of probable costs and opinion of O&M costs was developed for the No-
Diversion scenario for each alternative. The No-Diversion scenario costs (gas conditioning system
and electricity generation equipment) were then extrapolated to estimate costs for the two
diversion scenarios for each alternative. For the Low-Diversion scenario, costs were added for a
new anaerobic digester and waste receiving station. The estimated biogas quantities for each
1 Design TKN capacity of WWTP identified as 6,311 lb-N/d based on NPDES permit issued 05/01/2020
City of Iowa City | CAAP Methane Recovery Feasibility Study
Description of Project Alternatives
13
scenario as a basis for the extrapolation. Equipment proposals were also obtained for the
No-Diversion scenario for each alternative.
Table 2 contains a summary of the capital and O&M costs for each alternative selected for the
detailed SROI analysis.
Table 2: Biogas Utilization Alternatives Summary
Alternative Scenario Alternative
Designation
Opinion of
Probable
Construction
Costs
Opinion of
Probable Annual
O&M Costs
1a: WWTP NG
Pipeline Injection
No Diversion 1A - ND $8,600,000 $1,353,000
1,500 Ton/Year 1A - 1500 $10,800,000 $1,815,000
Low Diversion 1A - LD $41,400,000 $3,112,000
1b: Landfill NG
Pipeline Injection
No Diversion 1B - ND $29,200,000 $2,292,000
1,500 Ton/Year 1B - 1500 $29,000,000 $2,282,000
Low Diversion 1B - LD $28,000,000 $2,200,000
2a-2: WWTP
Electricity
Generation
No Diversion 2A - ND $13,500,000 $1,067,000
1,500 Ton/Year 2A - 1500 $17,000,000 $1,432,000
Low Diversion 2A - LD $50,000,000 $2,538,000
2b-2: Landfill
Electricity
Generation
No Diversion 2B - ND $20,500,000 $1,288,000
1,500 Ton/Year 2B - 1500 $20,300,000 $1,282,000
Low Diversion 2B - LD $19,600,000 $1,236,000
3: WWTP NG
Replacement
No Diversion 3 - ND $7,700,000 $867,000
1,500 Ton/Year 3 - 1500 $9,700,000 $1,163,000
Low Diversion 3 - LD $39,800,000 $2,136,000
4: Composting Low Diversion 4 $5,700,000 $495,000
4.7 Description of Impact Categories
The effect of an alternative differs across the individual impact categories (individual economic
and environmental benefits and/or costs) and depends on the design of the project alternative,
site conditions where the project is implemented, and characteristics in the community. Estimation
of benefits and costs from a project depends on the degree to which linkages can be quantified
between alternatives and a benefit or cost, and then available economic literature to value this
change.
This section develops the general assumptions and inputs used in the SROI analysis framework
and describes the impacts.
4.7.1 General Assumptions and Inputs
The SROI analysis measures benefits and costs throughout a 30-year period of analysis from
2021 to through the year 2050 representing the GHG emissions reduction goal year in the City’s
City of Iowa City | CAAP Methane Recovery Feasibility Study
Description of Project Alternatives
14
CAAP. The methodology makes several important assumptions and seeks to avoid
overestimation of benefits and underestimation of costs. Specifically:
• Input prices are inflated to 2019 dollars;
• The analysis period begins in 2021 and ends in 2050. It includes twenty-nine years of
operations (2022-2050); and
• A constant 3 percent real discount rate is assumed throughout the period of analysis.
4.7.2 Impact Categories
Each of the evaluated impacts is discussed in detail in the following sections. The impacts are
organized by their respective triple bottom line categorization (economic and environmental).
4.7.2.1 ECONOMIC IMPACTS
Economic benefits include impacts that are created by the project after deducting the cost of all
inputs, including the cost of the capital expenditures (CAPEX) and annual operations and
maintenance (O&M) costs (lifecycle costs of the project alternatives). Economic benefits include
value of RIN credits to the City. Additionally a non-monetary measure of economic efficiency
includes energy return on investment.
4.7.2.1.1 Lifecycle Costs
Lifecycle costs include CAPEX and annual O&M for each alternative. The costs are estimated as
a 30 year life-cycle costs as shown below in the S&L diagram.
Figure 7: Lifecycle Cost Structure and Logic Diagram.
Capital Costs
($ / yr)
O&M Costs
($ / yr)
Dis count Ra te
(%)
Total Cos ts
($ / yr)
Present Value of Total Costs
($)
4.7.2.1.2 RIN Credit Benefits
RIN credits provide a potential unique revenue source to Alternative 1. RINs are the credits that
the US Environmental Protection Agency (EPA) uses to track and enforce compliance with
the renewable fuels mandates set by the federal RFS Program. The City may be able to generate
and sell RIN credits to Obligated Parties by producing RNG from biogas and injecting it into the
pipeline for blending with conventional, non-renewable natural gas. Figure 8 illustrates the value
of RIN credits.
City of Iowa City | CAAP Methane Recovery Feasibility Study
Description of Project Alternatives
15
Figure 8: RIN Credit Value Structure and Logic Diagram.
RIN Credit Value ($/MMBTU)RNG Production (MMBTU/
Year)
Dis count Ra te
(%)Value of RIN Credits ($/Year)
Present V alue of RIN Credits
($)
The potential value of RIN credits beyond 2020 is shown below in Table 3. Based on this
information and discussions between the City and HDR, the median D3 value ($16.18) was used
in the SROI analysis for alternatives involving gas produced from the landfill. For alternatives
located at the WWTP and food waste diversion scenarios the D5 value ($7.70) was used
presuming the mix of a lesser quality gas.
Table 3: Value of RIN Credits
RIN and Carbon Market2
Units
Value
Most
likely Low Median High
Total for D3 + Commodity $/MMBTU $16.18 $8.20 $11.69 $25.15
Total for D5 + Commodity $/MMBTU $12.37 $5.71 $6.71 $9.70
Total for D5 + Commodity + LCFS $/MMBTU $7.70 $5.71 $11.69 $19.70
4.7.2.1.3 Renewable Electricity Production
Revenue from electricity sales are assumed to be captured from both net metering and negotiated
buyback agreements with MidAmerican Energy Company and Eastern Iowa Light and Power
Cooperative.
MidAmerican Energy Company (which supplies the electricity to the Iowa City Landfill) allows for
net metering agreements for a facility nameplate generation capacity of up to 1 megawatt (MW)
or 110% of its annual load. Credits from net metering agreements are paid out at the average
locational marginal price (LMP) from the Midcontinent Independent System Operator (MISO)
based on the generation profile of the resource. For energy produced beyond a nameplate
capacity of 1 MW or 110% of its annual load, energy can be sold to MidAmerican Energy at a
negotiated buyback rate. The Eastern Iowa Light and Power Cooperative allows for buyback
agreements for facilities with a nameplate generation capacity exceeding 20 kilowatts (kW).
Figure 9 illustrates the value of renewable electricity production.
2 HDR is NOT providing a revenue projection or analysis of financial feasibility of alternatives. Such
projections are highly dependent on open market commodity pricing, political volatility, and local, state, and
federal programs and policies.
City of Iowa City | CAAP Methane Recovery Feasibility Study
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Figure 9: Renewable Electricity Production Value Structure and Logic Diagram
Electricity Sales Rate ($/kWh)
Renewable Electricity
Production
(kWh/Year)
Discount Rate
(%)
Value of Rene wable Electricity
Production
($/Year)
Present Value of Renewable
Electricity P roduction
($)
Electricity production was monetized under the assumptions shown in Table 4. The landfill is
assumed to export 110% of its 2019 electricity usage at the net metered rate offered by
MidAmerican Energy Company, and any excess generation is monetized at the negotiated
buyback rate. The wastewater treatment plant receives the Eastern Iowa Light and Power
Cooperative avoided cost rate for all of its electricity generation.
Table 4: Value of Renewable Electricity Production
Electricity Sales Assumptions Units Value
MidAmerican Energy Net Metering Rate ¢/kWh 2.6¢3
MidAmerican Energy Negotiated Buyback Rate ¢/kWh 2.6¢4
Eastern Iowa Light and Power Cooperative Avoided Cost Rate ¢/kWh 4.2¢5
2019 Iowa City Landfill Electricity Usage kWh 278,882
4.7.2.1.4 Value of Avoided Natural Gas Purchases
The WWTP RNG produced will exceed the amount of natural gas used at the plant. As such, the
City would need to either: find a use for the excess RNG produced, flare the excess gas, or the
City would only condition the amount of biogas needed and the excess biogas would be flared.
Production of RNG would prevent the facility from needing to purchase natural gas. For this
analysis, it was assumed that RNG production would be capped at 62,848 standard cubic feet
3 The net metered rate is assumed to be a weighted average LMP based on 2019 hourly real-time LMP
prices for the Illinois hub and the MISO load. Calculated based on data from Midcontinent Independent
System Operator’s market reports.
***********.misoenergy.org/markets-and-operations/real-time--market-data/market-reports/#nt=.
MISO historical load data was gathered from EnergyOnline from January 1, 2019 to December 31, 2019.
**********.energyonline.com/Data/GenericData.aspx?DataId=17.
4 Negotiated buyback rate is assumed to be equivalent to the average LMP price calculated for the net
metering rate.
5 Weighted average calculation based on Eastern Iowa Light and Power Cooperative’s posted avoided cost
of generation during peak and off-peak hours.
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per day and valued at the delivered cost of natural gas at the facility assumed to be $3.166 per
MMBtu. The value stream is shown in Figure 10.
Figure 10: Renewable Natural Gas Value Structure and Logic Diagram
Natural Gas Price ($/MMBtu)
Renewable Natural G as
Produced
(MMBtu /Year)
Discount Rate
(%)
Value of Rene wable Natural
Gas Produced
($/Year)
Present Value of Renewable
Natural Gas Produce d
($)
4.7.2.1.5 Energy return on energy investment
Energy return on energy investment is the ratio of the amount of usable energy delivered from a
particular energy resource to the amount of energy used to obtain that energy resource as
illustrated below.
퐸푅푂퐸퐼 = 퐸표
퐸푖
Where:
Eo = Energy output
Ei = Energy input
The resulting ratio demonstrates the relative energy inputs necessary to produce the energy
output for each alternative. The higher the EROEI, the greater the amount of energy that is yielded
for the amount of energy produced. EROEI was estimated for each alternative except for
Alternative 4, because composting does not generate energy.
Energy output was based on the quantity of RNG produced or electricity generated. In addition to
energy generated, HDR also factored in lifecycle energy use reduction using the USEPA Waste
Reduction Model (WARM), which compares GHG emissions reductions and lifecycle energy
savings from baseline and alternative waste management scenarios. HDR estimated change in
lifecycle embodied energy by utilizing WARM to compare the baseline conditions to both 1,500
tons and Low-Diversion scenarios. Specifically, the output of the WARM model estimated the
lifecycle energy use reduction by co-digesting or composting additional diverted food waste as
compared to the baseline of landfilling this material. Because WARM is a lifecycle assessment
tool, meaning impacts are estimated from cradle-to-grave, the estimated energy use reduction
6 Calculated based on natural gas delivered and delivery charges from the wastewater treatment plant’s bill
for the month of October 2020.
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occurs outside of the City’s reporting boundary and would not be evident in annual GHG
emissions inventories.
Direct energy input is based on the parasitic load of new equipment installed for the purposes of
generating RNG or electricity, and does not include base load energy use required to operate the
WWTP and Landfill Facilities based on current conditions. Specifically, direct energy input
includes the parasitic load of the biogas conditioning equipment and electric generators. All
energy output and input measures were converted into million British thermal units (MMBtu) to
allow a relative comparison of alternatives. Table 5 provides details on each energy output and
input value. The resulting EROEI’s are presented in the results section of this report.
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Description of Project Alternatives
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Table 5: Estimated Energy Inputs for Each Alternative
Alternative
Description
Location Alternative Energy Input Energy Output
(Lifecycle Output + Lifecycle Energy Reduction)
EROEI
kW/hr1 lifecycle
(MMBTU)
RNG
(scfm)2
kW-
hr/day1
Lifecycle
Output
(MMBTU)
Lifecycle
Energy
Reduction
(MMBTU)
Total
Lifecycle
Energy
Output
(MMBTU)
Pipeline
Injection
WWTP Alt. 1a - ND 158 141,680 71 0 1,056,062 0 1,056,062 7.5
Alt. 1a - 1500 Div 243 217,901 95 0 1,417,070 0 1,497,046 6.9
Alt. 1a - LD 375 336,266 142 0 2,121,111 79,976 2,545,515 7.6
Landfill Alt. 1b - ND 1,145 1,026,733 541 0 8,096,474 424,404 8,096,474 7.9
Alt. 1b - 1500 Div 1,145 1,026,733 536 0 8,026,070 0 8,106,045 7.9
Alt. 1b - LD 1,145 1,026,733 515 0 7,710,000 79,976 8,134,404 7.9
Electricity
Generation
WWTP Alt. 2a - ND 305 273,497 0 10,915 407,816 424,404 407,816 1.5
Alt. 2a - 1500 Div 353 316,539 0 14,644 547,143 0 627,118 2.0
Alt. 2a - LD 650 582,862 0 21,921 819,033 79,976 1,243,437 2.1
Landfill Alt. 2b - ND 317 284,257 0 94,517 3,531,432 424,404 3,531,432 12.4
Alt. 2b - 1500 Div 317 284,257 0 93,695 3,500,720 0 3,580,696 12.6
Alt. 2b - LD 317 284,257 0 89,997 3,362,552 79,976 3,786,956 13.3
Natural Gas
Replacement
WWTP Alt. 3 - ND 158 141,680 71 0 653,776 424,404 653,776 4.6
Alt. 3 - 1500 Div 243 217,901 95 0 653,776 0 733,752 3.4
Alt. 3 - LD 650 582,862 142 0 653,776 79,976 1,078,180 1.8
Expanded
Composting
Compost Alt. 4 0 0 0 0 0 424,404 0 0.0
Notes:
1) The conversion from kw/hr to MMBTU is: kw/hr * 24 hours * 3,412.14 BTU per kW/hr * 365 days * 30 years divided by 1,000,000.
2) The conversion from scfm to MMBTU is: scfm * 1440 mins/day * 950 BTU per scfm natural gas * 365 days * 30 years divided by 1,000,000.
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4.7.2.2 ENVIRONMENTAL IMPACTS
Environmental benefits include impacts that are valued based on the project’s change in natural
resource quality or quantity. The environmental included in this analysis include the social cost of
carbon measured by changes in the emissions of carbon dioxide equivalents (CO2e).
4.7.2.2.1 Social Cost of Carbon
GHG Emissions Impact Assessment: HDR understands that a key driver for decision-making
is understanding the relative GHG emissions impact associated with each alternative and making
progress towards the City’s climate action goals. GHG emissions were estimated for each
alternative included in the SROI analysis, and considered both direct and lifecycle impacts , as
well as avoided emissions resulting from the beneficial reuse of biogas . Calculation
methodologies align with best practices described in the Global Protocol for Community-Scale
Greenhouse Gas Emission Inventories (GPC) and Local Government Operations Protocol
(LGOP) for GHG assessment. These considerations are described below and cumulative GHG
emissions impacts for each alternative are presented in Table 6.
• Direct GHG emissions were based on the incremental emissions resulting from processes
required to beneficially reuse biogas. Specifically, direct GHG emissions are based on the
parasitic load of new equipment installed for the purposes of generating RNG or electricity,
such as energy consumed by the biogas conditioning equipment and electric generators.
It is important to note that direct emissions do not include base load energy use required
to operate the WWTP and Landfill Facilities based on current conditions, rather, the
Feasibility Study analyzes the incremental change from current operations. At the City’s
direction, HDR assumed that there would not be a material change in transportation -
related GHG emissions associated with diverting food waste for the 1,500 tons and Low-
Diversion scenarios. Lastly, it should be noted that GHG emissions associated with
combustion of biogas/RNG is considered biogenic (CO2(b)), and per the GPC, is to be
reported separately outside of Scope 1, 2, and 3 GHG emission categories. Biogenic
emissions are those related to the natural carbon cycle, as well as those resulting from
the combustion, harvest, digestion, fermentation, decomposition or processing of
biologically based materials.
• Lifecycle GHG emissions were estimated using the EPA WARM, which compares GHG
emissions reductions and lifecycle energy savings from baseline and alternative waste
management scenarios. HDR estimated change in lifecycle embodied carbon by utilizing
WARM to compare the baseline conditions to both 1,500 tons and Low-Diversion
scenarios. Specifically, the output of the WARM model estimated the lifecycle energy use
reduction by co-digesting or composting additional diverted food waste as compared to
the baseline of landfilling this material. Because WARM is a lifecycle assessment tool,
meaning impacts are estimated from cradle-to-grave, the estimated GHG emissions
reduction occurs outside of the City’s reporting boundary and would not be evident in
annual GHG emissions inventories.
• Avoided GHG emissions were estimated based on the beneficial reuse of biogas,
including pipeline injection, electricity generation, and natural gas displacement,
assuming:
o Biogas injected into the natural gas pipeline would be utilized to generate and sell
RIN credits, ultimately being used as a renewable fuel for mobile source
City of Iowa City | CAAP Methane Recovery Feasibility Study
Description of Project Alternatives
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combustion. RNG is a market driver for commercial fleets to transition away from
conventional diesel trucks to compressed natural gas (CNG)/RNG alternate
fueled-vehicles. GHG emission reductions were estimated using a diesel fuel
emissions factor published by the EPA.
o Biogas used to generate electricity would ultimately offset electricity generated by
local electric power utilities (MidAmerican Energy or Eastern Iowa Light & Power).
Emission factors were provided by the City. While MidAmerican Energy does have
a public goal related to 100% of retail sales being served by renewable energy,
this is not equivalent to a net zero carbon production goal. Absent of either electric
utility having a publicly stated carbon emissions reduction goal, GHG emission
reductions were estimated using the emission factor provided by the City, held
constant for the study period.
o Biogas used as onsite fuel at the WWTP would displace natural gas on a 1:1 unit
basis. GHG emission reductions were estimated using a natural gas emissions
factor published by the EPA.
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Description of Project Alternatives
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Table 6: Estimated GHG Emissions
Alternative
Description
Location Alternative Change in
Landfill
GHG
Inventory
Parasitic
energy
load
Change in
biological
treatment
inventory
Beneficial
reuse GHG
benefit
Change in
Net
Embodied
Carbon (EPA
WARM)
Total
Annual
Change in
CO2e Metric
Tons
Pipeline
Injection
WWTP Alt. 1a - ND 0 666 0 -2,017 0 -1,351
Alt. 1a - 1500 Div 1,027 0 27 -2,707 -941 -2,594
Alt. 1a - LD 1,585 0 144 -4,052 -4,996 -7,318
Landfill Alt. 1b - ND 0 4,840 0 -32,190 0 -27,350
Alt. 1b - 1500 Div 0 4,840 0 -32,047 -941 -28,148
Alt. 1b - LD 0 4,840 0 -30,903 -4,996 -31,059
Electricity
Generation
WWTP Alt. 2a - ND 0 1,289 0 -1,922 0 -633
Alt. 2a - 1500 Div 1,492 0 27 -2,579 -941 -2,001
Alt. 2a - LD 2,748 0 144 -3,861 -4,996 -5,965
Landfill Alt. 2b - ND 0 1,340 0 -16,647 0 -15,307
Alt. 2b - 1500 Div 0 1,340 0 -13,282 -941 -12,884
Alt. 2b - LD 0 1,340 0 -15,851 -4,996 -19,507
Natural Gas
Replacement
WWTP Alt. 3 - ND 0 666 0 -2,030 0 -1,363
Alt. 3 - 1500 Div 0 1,027 27 -4,076 -941 -3,963
Alt. 3 - LD -7,221 144 2,748 -4,076 -4,996 -13,401
Expanded
Composting
Compost Alt. 4
-7,221 0 0 722 -5,670 -12,169
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Value of GHG Emissions: Scientific studies in the United States and internationally have widely
concluded that GHG emissions are closely linked with climate change, a condition that has been
determined to lead to future economic impacts from more extreme weather events and damaging
conditions on coasts. The impact is estimated from the change in energy production and net
embodied carbon in each of the waste diversion scenarios. In alternatives of 1A and 1B (pipeline
injection), RIN credits are counted as an economic benefit and the environmental attributes would
therefore be sold to Obligated party who purchases the RIN credits. As such, the value of the
social cost of carbon (SCC) is not counted for the associated changes in GHG emissions to avoid
double counting.
GHG impacts were estimated using:
• EPA WARM model for the change in metric tons of CO2e from embodied carbon in the
waste stream;
• an electricity conversion factor (converts megawatt hours to tons of pollution for each
emission type); and
• a cost of emission (monetizes the impact).
The logic for the estimating impacts of changes in GHG emissions is illustrated in Figure 11.
Figure 11: GHG Emissions Structure and Logic Diagram.
Parasitic Energy Consumption
(kWh / yr)
GHG Emiss ions Rate
(tons / kWh)
Dis count Ra te
(%)
Net Change in GHG
(tons / yr)
Pre sent Value of Total Costs
($)
Net Embodied GHG E missions -
EPA WARM Model
(tons / yr)
Emissions Reduction Biogas
Reuse
(tons / yr)
Economic Value of GHG –
Social Cost of Carbon
($ / ton)
Net GHG SCC ($ / yr)
For CO2e; the value from the Interagency Working Group on the Social Cost of Carbon (IWGSCC)
was used in the analysis. This value is then escalated annually at 2% using rates derived from
the Federal Interagency Working Group on Social Cost of Carbon. All values are in 2019 US
dollars per ton.
Table 7: Social Costs of GHG Emissions
GHG Emissions Unit Value Source
CO2e $/Ton $46 IWGSCC (2013)
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Summary Economic, and Environmental Impacts of Alternatives
24
5 Summary Economic, and Environmental
Impacts of Alternatives
The evaluation of economic and environmental impacts considered a time horizon or study period,
which includes project development (construction and implementation) and 29 years of operation
and benefit. This extends to 2050 and aligns with the planning horizon of the City’s CAAP. Costs
and benefits have been converted to present value using a 3% discount factor. Total benefits and
costs are compared using a benefit to cost ratio (BCR), benefits divided by costs. BCR’s
exceeding 1.0 indicate that the benefits from the alternative exceed the costs of the in vestment
over a 30 year period. Results are shown below in Table 8.
Consideration should be given to the implementation schedule of alternatives and potential for a
phased approach. Revising the economic framework to account for a phasing of projects over
5-10 years would affect all of the alternatives equally and would not change the overall ranking or
comparison of the alternatives. Furthermore, there is limited impact to the capital and O&M cost
considerations as long as the period of study remains over 30-years. The more significant cost
impacts are observed with a minimum delay of 8-10 years out of the study period. A number of
implementation scenarios are possible, but the CIP planning impact is often similar from a
planning perspective.
Table 8: Summary of Monetary Benefits and Costs ($ Millions, 2019)
Alternative
Description
Location Alternative Total
Cost
Total
Social
Cost of
Carbon
Total Value
for RIN Credit
and Energy
Revenues
Total
Benefit
Benefit
-Cost
Ratio
Pipeline
Injection
WWTP Alt. 1a - ND $35.92 $1.67 $5.48 $7.15 0.20
Alt. 1a - 1500 $47.44 $3.21 $7.35 $10.56 0.22
Alt. 1a - LD $104.23 $18.01 $23.09 $41.10 0.39
Landfill Alt. 1b - ND $75.47 $33.87 $88.14 $122.01 1.62
Alt. 1b - 1500 $75.07 $34.86 $87.37 $122.23 1.63
Alt. 1b - LD $72.42 $38.46 $83.93 $122.39 1.69
Electricity
Generation
WWTP Alt. 2a - ND $35.04 $0.78 $1.58 $1.91 0.05
Alt. 2a - 1500 $45.91 $2.48 $2.71 $4.41 0.10
Alt. 2a - LD $101.24 $16.33 $2.77 $18.31 0.18
Landfill Alt. 2b - ND $46.50 $18.96 $27.16 $35.23 0.76
Alt. 2b - 1500 $46.18 $15.95 $26.91 $32.08 0.69
Alt. 2b - LD $44.55 $24.16 $25.75 $39.58 0.89
Natural Gas
Replacement
WWTP Alt. 3 - ND $25.20 $1.69 $1.09 $2.78 0.11
Alt. 3 - 1500 $33.18 $3.23 $0.93 $4.16 0.13
Alt. 3 - LD $82.92 $16.60 $0.15 $16.75 0.20
Expanded
Composting
Compost Alt. 4
$15.69 $15.07 $0.00 $15.07 0.96
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Summary Economic, and Environmental Impacts of Alternatives
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The results show that only Alternative 1b (landfill natural gas) has benefits that exceed the costs.
The highest BCR is Alternative 1b – Low-Diversion. This alternative ranks highest on total lifecycle
CO2e emission reductions, and when combined with the value of RIN credits results in the
greatest economic benefits. However, the City should be aware that the CO2e emission reduction
when RINs are sold to an Obligated Party will occur outside of the City’s municipal and
community-scale GHG inventories. This alternative has the sixth highest cost of the 15
alternatives presented. The net result, of Alternative 1b, is a BCR of 1.69 dollars of benefit per
dollar of cost invested.
A sensitivity test was conducted to test the impact of key monetary values (RIN credits and SCC
values) on the ranking of the alternatives. Changing the value of the SCC was found to have no
effect in ranking as the value influences all of the alternatives equally. Conversely, the RIN credit
value only affects the BCR of pipeline injection alternative (Alternative 1) and would have an
impact on alternative ranking. The sensitivity analysis showed that the realized RIN credit value
would need to be below $6.00 per MMBTU, or 5% greater than the low value of D5 RIN credits
shown Table 3 for the BCR ranking of alternatives to change.
Perhaps as important for consideration in CAAP are non-monetary considerations. The non-
monetary metrics (EROEI and lifecycle change in CO2e emissions) are shown in Table 9. Perhaps
the most important measure related to CAAP action objectives is CO2e reductions. All of the
alternatives result in a net reduction in CO2e over the next 30 years. Alternative 1b – Low-
Diversion results in the greatest net reduction.
Table 9: Summary of Non-Monetary Impacts
Alternative
Description
Location Alternative Lifecycle Change in
CO2e Emissions
Lifecycle
EROEI
Pipeline Injection WWTP Alt. 1a - ND 40,500 6.9
Alt. 1a - 1500 77,800 7.9
Alt. 1a – LD 436,200 7.9
Landfill Alt. 1b - ND 820,500 7.5
Alt. 1b - 1500 844,500 7.6
Alt. 1b - LD 931,800 7.9
Electricity
Generation
WWTP Alt. 2a - ND 19,000 2.0
Alt. 2a - 1500 60,000 12.4
Alt. 2a - LD 395,600 13.3
Landfill Alt. 2b - ND 459,200 1.5
Alt. 2b - 1500 386,500 2.1
Alt. 2b - LD 585,200 12.6
Natural Gas
Replacement
WWTP Alt. 3 - ND 40,900 4.6
Alt. 3 - 1500 78,300 3.4
Alt. 3 - LD 252,200 1.8
Expanded
Composting
Compost Alt. 4 365,100 0.0
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Summary Economic, and Environmental Impacts of Alternatives
26
Finally, all alternatives, except for composting, result in an EROEI of 1.0 or greater. Incremental
composting of food waste does not generate energy . Opposite of the economic and GHG
measures, Alternative 2a (WWTP Electricity Generation) – Low-Diversion ranks highest on
EROEI. Meanwhile Alt 1b – Low-Diversion is ranked 5th on EROEI.
The overall ranking of the alternatives for the monetary (BCR) and the two non-monetary results
are shown below in Table 10.
Table 10: Summary and Ranking of Monetary and Non-Monetary Results
Alternative
Description
Location Alternative GHG
Reduction
GHG
Rank
EROEI EROEI
Rank
BCR BCR
Rank
Pipeline
Injection
WWTP Alt. 1a - ND 40500 15 6.9 9 0.20 11
Alt. 1a - 1500 77800 12 7.9 6 0.22 9
Alt. 1a - LD 436200 6 7.9 4 0.39 8
Landfill Alt. 1b - ND 820500 3 7.5 8 1.62 3
Alt. 1b - 1500 844500 2 7.6 7 1.63 2
Alt. 1b - LD 931800 1 7.9 5 1.69 1
Electricity
Generation
WWTP Alt. 2a - ND 19000 16 2.0 13 0.05 16
Alt. 2a - 1500 60000 13 12.4 3 0.10 15
Alt. 2a - LD 395600 8 13.3 1 0.18 12
Landfill Alt. 2b - ND 459200 5 1.5 15 0.76 6
Alt. 2b - 1500 386500 9 2.1 12 0.69 7
Alt. 2b - LD 585200 4 12.6 2 0.89 5
Natural Gas
Replacement
WWTP Alt. 3 - ND 40900 14 4.6 10 0.11 14
Alt. 3 - 1500 78300 11 3.4 11 0.13 13
Alt. 3 - LD 402000 7 1.8 14 0.20 10
Expanded
Composting
Compost Alt. 4 365100 10 0.0 16 0.96 4
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5.1 Findings and Insights
To make recommendations for actions under 3.7 and 3.8, the monetary and non-monetary results
are combined into a weighted score as shown below in Table 11. Each result was converted to
an index (1 to 0). The indexed results were then weighted equally into a total score with a
maximum value of 1.
Table 11: Indexed and Weighted Scores for each Alternative
Alternative
Description
Location Alternative GHG
Reducti
on
EROEI BCR Total
Score
Rank
Pipeline
Injection
WWTP Alt. 1a - ND 0.01 0.17 0.04 0.23 13
Alt. 1a - 1500 0.03 0.20 0.04 0.27 11
Alt. 1a - LD 0.16 0.20 0.08 0.43 6
Landfill Alt. 1b - ND 0.29 0.19 0.32 0.80 3
Alt. 1b - 1500 0.30 0.19 0.32 0.81 2
Alt. 1b - LD 0.33 0.20 0.33 0.86 1
Electricity
Generation
WWTP Alt. 2a - ND 0.01 0.05 0.01 0.07 16
Alt. 2a - 1500 0.02 0.31 0.02 0.35 7
Alt. 2a - LD 0.14 0.33 0.04 0.51 5
Landfill Alt. 2b - ND 0.16 0.04 0.15 0.35 8
Alt. 2b - 1500 0.14 0.05 0.14 0.33 9
Alt. 2b - LD 0.21 0.32 0.18 0.70 4
Natural Gas
Replacement
WWTP Alt. 3 - ND 0.01 0.12 0.02 0.15 14
Alt. 3 - 1500 0.03 0.08 0.02 0.14 15
Alt. 3 - LD 0.14 0.05 0.04 0.23 12
Expanded
Composting
Compost Alt. 4 0.13 0.00 0.19 0.32 10
As noted previously, the Alternative 1b-LD (Landfill RNG Pipeline Injection) – Low-Diversion has
the highest BCR. It also has the highest GHG reduction over 30 years. This is driven by the
assumption that biogas injected into the natural gas pipeline would be utilized to generate and
sell RIN credits, ultimately being used as a renewable fuel for mobile source combustion. Further,
RNG is a market driver for commercial fleets to transition away from conventional diesel trucks to
compressed natural gas (CNG)/RNG alternate fueled-vehicles. However, the City should be
aware that when RINs are sold to an Obligated Party, the CO2e emission reduction will occur
outside of the City’s municipal and community-scale GHG inventories. Opposite of the economic
and GHG impacts, Alternative 2a (WWTP Electricity Generation) – Low-Diversion ranks highest
on EROEI. Meanwhile Alternative 1b – Low-Diversion is ranked 5th on EROEI.
Based on the indexing and weighting exercise, Alternative 1b (Landfill Natural Gas) – Low-
Diversion has the highest score (0.86). Alternative 1b (landfill natural gas) – 1500 ton diversion is
ranked second. Alternative 1b (landfill natural gas) – No-Diversion is ranked third. Again, CO2e
emission reduction associated with pipeline injection and used as a renewable fuel will occur
outside of the City’s municipal and community-scale GHG inventories.
City of Iowa City | CAAP Methane Recovery Feasibility Study
Summary Economic, and Environmental Impacts of Alternatives
28
If the City is instead focused on reductions that will be reflected in its municipal and community -
scale GHG emission inventory, then evaluation should be narrowed to focus on Alternatives 2
(Electricity Generation) and 3 (Natural Gas Replacement). While electricity generated at the
WWTP or Landfill (2a and 2b, respectively) could very well be pushed to the power grid,
contractual agreements with local utilities could allow the City to retain and retire REC s for GHG
accounting purposes. Specifically, RECs could be applied to the City’s Scope 2 market-based
GHG inventory. Using RNG to displace natural gas use at the WWTP would result in lower Scope
1 GHG emissions. Focused on these two alternatives, Alternative 2b – Low-Diversion is ranked
highest (fourth overall), followed by Alternatives 2a – Low-Diversion and 2a – 1500. These
alternatives are ranked 4, 5 and 7 overall.
If total GHG emissions reduction is the ultimately priority, Alternatives 1b (Landfill Pipeline
Injection) offers the greatest potential, simply due to the volume of biogas generation and
associated potential for renewable electricity generation.
Finally, biogas utilization alternatives can be combined together with others, and some can be
incorporated as standalone projects (as shown in Table 12).
Table 12: Potential Biogas Utilization Alternatives Combinations
There are 18 unique possible combinations of alternatives, Table 12 has been developed to more
appropriately showcase combinations and the “diversion lanes” in which decisions would need to
be maintained with a decision. Boxes with blue numbering indicate individual alternative scenarios
NG Pipeline
Injection
Electricity
Generation
NG Pipeline
Injection
Electricity
Generation
NG Pipeline
Injection
Electricity
Generation
Alt 1b-ND Alt 2b-ND Alt 1b-1500 Alt 2b-1500 Alt 1b-LD Alt 2b-LD
0 0.80 0.35 0.81 0.33 0.86 0.70
NG Pipeline
Injection Alt 1a-ND 0.23 1.02 0.58
Electricity
Generation Alt 2a-ND 0.07 0.87 0.42
NG
Replacement Alt 3-ND 0.15 0.95 0.50
NG Pipeline
Injection Alt 1a-1500 0.27 1.08 0.60
Electricity
Generation Alt 2a-1500 0.35 1.16 0.68
NG
Replacement Alt 3-1500 0.14 0.95 0.47
NG Pipeline
Injection Alt 1a-LD 0.43 1.30 1.13
Electricity
Generation Alt 2a-LD 0.51 1.37 1.21
NG
Replacement Alt 3-LD 0.23 1.09 0.93
Landfill Location
No Diversion 1500 ton/yr Diversion Low Diversion
Do Nothing
Weighted and Indexed Performance
Indicators
Total Score, inclusive of:
GHG Reduction, EROI, and BCR
Do Nothing
City of Iowa City | CAAP Methane Recovery Feasibility Study
Summary Economic, and Environmental Impacts of Alternatives
29
at either the Landfill or at the WWTP. The boxes are also color coded in a “heat map” format, to
show the overall ranking of the individual scenarios.
The individual alternatives can be combined together, but must be done so following the same
waste diversion scenario from the Landfill. When combining the alternatives the scores from the
Landfill and WWTP alternatives can be added together to identify the best combination of actions
under each of the waste diversion scenarios. From Table 11 above, the higher the score the better
the alternative. The highest scored alternatives are: Alternative 1b – NG Pipeline Injection landfill
alternatives for each of the No-Diversion, 1500 ton diversion, and Low-Diversion scenarios.
Identifying the best combination of actions works as follows: select the highest scored alternative
from the desired waste diversion scenario (shown to be from the Alternative 1b – NG Pipeline
Injection landfill alternatives) then work down the column (or “diversion lane”) to the desired
combination scenario. In the case of combining with Alternative 2a – Electricity Generation at the
WWTP, a resulting combined score of 1.16. As capital costs are also additive, consideration
should be given to the seemingly minor weighted score differential. In the example of combined
Alt 1b-1500 with Alt 2a-1500, there is an estimated $6.2M savings to select Alt 1b-1500 with Alt
1a-1500.
5.1.1 Path Forward
HDR recognizes that incremental food waste diversion is not an instantaneous process, but the
SROI analysis provides an assessment of the resulting impact when achieved. This Report
provides decision tools to support the City’s further consideration and decision making.
Consequently, the City might consider the following path forward to further evaluate and
implement the preferred alternative(s):
i. City decision on desired diversion scenario and methane utilization at the WWTP to
narrow the field of alternatives. (0-6 months)
ii. Further technical analysis to develop organics management strategies to achieve a
targeted diversion scenario and further evaluate life cycle costs of co-digestion (if desired)
and biogas utilization to generate electricity or RNG. Consideration of impacts to planned
digester rehab project. (3-6 months)
iii. Conceptual Design Development of the selected alternative(s), providing basis of design
parameters and implementation planning. (3-6 months)
iv. Detailed Design Development. (TBD)
v. Bidding and Construction. (TBD)
It may be prudent for the City to complete items i) and ii) within the next 6-months for capital
planning purposes.
City of Iowa City | CAAP Methane Recovery Feasibility Study
References:
30
6 References:
City of Iowa City (2018), Climate Action and Adaptation Plan,
https://www.icgov.org/project/climate-action.
City of Iowa City (2019), City Resolution 19-218, https://www.icgov.org/project/climate-action.
City of Iowa City, (2020), Accelerating Iowa City’s Climate Action Plan,
https://www.icgov.org/project/climate-action.
Clinton Global Initiative, (2007), https://www.clintonfoundation.org/clinton-global-
initiative/commitments/creating-sustainable-return-investment-sroi-tool.
Interagency Working Group on Social Cost of Carbon (IWGSCC), United States Government.
(2010). Technical Support Document: Social Cost of Carbon for Regulatory Impact
Analysis Under Executive Order 12866.
U.S. Environmental Protection Agency (2019). Environmental Protection Agency Waste
Reduction Model (WARM) version 15. https://www.epa.gov/warm/versions-waste-
reduction-model-warm#15.
City of Iowa City | CAAP Methane Recovery Feasibility Study
Appendix A
A
Appendix A
Low-Diversion Scenario
Digester Costs
Costs
Hauled Waste Receiving Station $2,960,000
Anaerobic Digester (1.4 MG)$18,325,000
Sludge Dewatering and Storage $4,990,000
$26,300,000
General O&M - Parts, Labor, Electricity 1.5% of capital subtotal $394,500
$394,500
Low Diversion Scenario (20% Diversion) - New Anaerobic Digester Complex
Capital Cost
Total Adjusted Base Bid with Installation
Annual O&M Cost Annual O&M Costs
OPINION OF PROBABLE CONSTRUCTION COSTS
City of Iowa City | CAAP Methane Recovery Feasibility Study
Appendix B
B
Appendix B
Financial Proforma –
Breakeven Analysis
City of Iowa City | CAAP Methane Recovery Feasibility Study
Appendix B - Memo | Financial Proforma - Breakeven Analysis
1
Appendix B - Memo
Date: Wednesday, December 23, 2020
Project: CAAP Methane Recovery Feasibility Study (HDR #10203725)
To: City of Iowa City (PM – Joseph Welter)
From: HDR (PM – Morgan Mays; Marcella Thompson; Serguei Kouznetsov; Jeremy Cook)
Subject: Financial Proforma - Breakeven Analysis
Building on the Sustainable Return on Investment (SROI) and the Energy Return on Energy
Invested (EROEI) analysis performed by HDR, a high-level breakeven financial analysis was
performed for each of the options identified in the Final Feasibility Report. The financial analysis
examines the impact of cash flows to Iowa City (the City) to compare the revenues (inflows) and
costs (outflows). The purpose of the analysis was to identify the length of time for each
alternative to break-even. This memorandum outlines the cash flows evaluated, key
assumptions, and the results of the analysis.
Key Assumptions
The financial analysis examined revenue streams for the various alternatives. For the pipeline
injection alternatives, the revenue is derived from the Renewable Identification Number (RIN)
credits under the Renewable Fuel Standard Program. For the electricity generation alternatives,
the revenue is derived from electricity sales through an agreement with the utilities and
Renewable Energy Credits (RECs). For natural gas replacement alternatives, revenue or rather
savings are derived from avoided natural gas purchases.
Revenue from electricity sales are assumed to be captured from both net metering and
negotiated buyback agreements with MidAmerican Energy Company and Eastern Iowa Light
and Power Cooperative.
MidAmerican Energy Company (which supplies the electricity to the Iowa City Landfill) allows for
net metering agreements for a facility nameplate generation capacity of up to 1 megawatt (MW).
Credits from net metering agreements are paid out at the average locational marginal price
(LMP) from the Midcontinent Independent System Operator (MISO) based on the generation
profile of the resource. For energy produced beyond a nameplate capacity of 1 MW, energy can
be sold to MidAmerican Energy at a negotiated buyback rate. The Eastern Iowa Light and
Power Cooperative allows for buyback agreements for facilities with a nameplate generation
capacity exceeding 20 kilowatts (kW). RECs are earned for each megawatt-hour (MWh) of
electricity generated. For the purposes of this analysis, an average LMP of 2.6¢1 per kilowatt-
hour (kWh) was calculated based on the 2019 LMP prices for the Illinois hub and the 2019
1 Real time LMP prices gathered from Midcontinent Independent System Operator (MISO)’s historical
LMPs for real-time markets from January 1, 2019 to December 31, 2019.
***********.misoenergy.org/markets-and-operations/real-time--market-data/market-reports/#nt=.
MISO historical load data was gathered from EnergyOnline from January 1, 2019 to December 31, 2019.
**********.energyonline.com/Data/GenericData.aspx?DataId=17.
City of Iowa City | CAAP Methane Recovery Feasibility Study
Appendix B - Memo | Financial Proforma - Breakeven Analysis
2
MISO load. This was assumed to be the price paid per kWh for MidAmerican Energy’s net
metering agreements. It was also assumed that the negotiated buyback rate for electricity
generation in excess of 1 MW was equivalent to the average LMP price of 2.6¢ per kWh.
Eastern Iowa Light and Power Cooperative posts its avoided cost of generation during peak and
off-peak hours online from which a weighted average rate of 4.2¢ per kWh was calculated for
energy sales from the wastewater treatment plant.
Renewable energy credits were monetized at an average rate of $17 per MWh based on the
latest auction prices of $16.93 per MWh in and the approximate band of prices over the past
couple of years (see figure below). The analysis assumed that prices would remain at that price
for the full 30 years of the analysis.
Figure 1: Historical Auction Prices for Renewable Energy Credits2
As mentioned in the main report, the WWTP RNG produced will exceed the amount of natural
gas used at the plant. As such, the City would need to either: find a use for the excess RNG
produced, flare the excess gas, or the City would only condition the amount of biogas needed
2 California Air Resources Board. California and Quebec Carbon Allowance Prices, December 4, 2020.
********ww2.arb.ca.gov/sites/default/files/2020-09/carbonallowanceprices_0.pdf.
City of Iowa City | CAAP Methane Recovery Feasibility Study
Appendix B - Memo | Financial Proforma - Breakeven Analysis
3
and the excess biogas would be flared. For this analysis, it was assumed that RNG production
would be capped at 62,848 standard cubic feet per day and valued at the delivered cost of
natural gas at the facility assumed to be $3.16 per MMBtu.
Results
High level results of the financial analysis are presented in the tables below. Projects were
assumed to be bonded at a 3% interest rate and the breakeven term represents the minimum
financing term that would be needed for the project to break even financially. Many alternatives
have a payback term that is longer than 30 years, making them infeasible without grant funding
support.
Table 1: Lifecycle Financial Breakeven Analysis Results, Millions of 2019$
Alternative
Description
Location Alternative Total
Cost
Total
Financial
Benefit
Project
NPV (3%
bond rate)
Financial
Breakeven
Term
Pipeline
Injection
WWTP Alt. 1a - ND $35.92 $5.48 -$30.44 N/A
Alt. 1a - 1500 Div $47.44 $7.35 -$40.10 N/A
Alt. 1a - LD $104.23 $23.09 -$81.14 N/A
Landfill Alt. 1b - ND $75.47 $88.14 $12.67 17.9 years
Alt. 1b - 1500 Div $75.07 $87.37 $12.30 18.0 years
Alt. 1b - LD $72.42 $83.93 $11.52 18.2 years
Electricity
Generation
WWTP Alt. 2a - ND $35.04 $1.58 -$33.47 N/A
Alt. 2a - 1500 Div $45.91 $2.71 -$43.21 N/A
Alt. 2a - LD $101.24 $2.77 -$98.47 N/A
Landfill Alt. 2b - ND $46.50 $27.16 -$19.34 N/A
Alt. 2b - 1500 Div $46.18 $26.91 -$19.28 N/A
Alt. 2b - LD $44.55 $25.75 -$18.81 N/A
Natural Gas
Replacement
WWTP Alt. 3 - ND $25.20 $1.09 -$24.11 N/A
Alt. 3 - 1500 Div $33.18 $0.93 -$32.25 N/A
Alt. 3 - LD $82.92 $0.15 -$82.77 N/A
Expanded
Composting
Compost Alt. 4 $15.69 $0.00 -$15.69 N/A
Table 2: Annual Financial Breakeven Analysis Results
Alternative
Description Location Alternative
Annual Debt
Service on
Capital Costs
Annual
Operating
Costs
Annual
Revenues/
Savings
Net
Annual
Financial
Impact
Pipeline
Injection
WWTP Alt. 1a - ND $0.44 $1.35 $0.27 -$1.52
Alt. 1a - 1500 Div $0.55 $1.82 $0.36 -$2.00
Alt. 1a - LD $2.11 $3.11 $1.14 -$4.08
Landfill Alt. 1b - ND $1.49 $2.29 $4.37 $0.58
Alt. 1b - 1500 Div $1.48 $2.28 $4.33 $0.57
Alt. 1b - LD $1.43 $2.20 $4.16 $0.53
WWTP Alt. 2a - ND $0.69 $1.07 $0.08 -$1.68
City of Iowa City | CAAP Methane Recovery Feasibility Study
Appendix B - Memo | Financial Proforma - Breakeven Analysis
4
Alternative
Description Location Alternative
Annual Debt
Service on
Capital Costs
Annual
Operating
Costs
Annual
Revenues/
Savings
Net
Annual
Financial
Impact
Electricity
Generation
Alt. 2a - 1500 Div $0.87 $1.43 $0.13 -$2.17
Alt. 2a - LD $2.55 $2.54 $0.14 -$4.95
Landfill Alt. 2b - ND $1.05 $1.29 $1.35 -$0.99
Alt. 2b - 1500 Div $1.04 $1.04 $1.33 -$0.74
Alt. 2b - LD $1.00 $1.24 $1.28 -$0.96
Natural Gas
Replacement
WWTP Alt. 3 - ND $0.39 $0.87 $0.05 -$1.21
Alt. 3 - 1500 Div $0.49 $1.16 $0.05 -$1.61
Alt. 3 - LD $2.03 $2.14 $0.01 -$4.16
Expanded
Composting
Compost Alt. 4 $0.29 $0.50 $0.00 -$0.79
Given that many of the alternatives do not generate enough financial benefits to break even in a
reasonable time frame, the HDR team considered whether grant funding support could make
the project feasible. The table below presents the minimum amount of grant funding required for
each project to break even within specific time frames. Since grant funding is used to support
up-front project capital costs, amounts above the initial capital costs are highlighted in red as not
feasible. Amounts in green are feasible with the specified amount of grant funding.
Table 3: Grant Funding Support Necessary for Projects to Break Even
Alternative
Description Location Alternative
Initial
Project
Capital
Cost
Baseline
Financial
Breakeven
Term
Grant Funding
Support to
Break Even
within 30 Years
Pipeline
Injection
WWTP Alt. 1a - ND $8.60 N/A $30.44
Alt. 1a - 1500 Div $10.80 N/A $40.10
Alt. 1a - LD $41.40 N/A $81.14
Landfill Alt. 1b - ND $29.20 17.9 years $0
Alt. 1b - 1500 Div $29.00 18.0 years $0
Alt. 1b - LD $28.00 18.2 years $0
Electricity
Generation
WWTP Alt. 2a - ND $13.50 N/A $33.47
Alt. 2a - 1500 Div $17.00 N/A $43.21
Alt. 2a - LD $50.00 N/A $98.47
Landfill Alt. 2b - ND $20.50 N/A $19.34
Alt. 2b - 1500 Div $20.30 N/A $19.28
Alt. 2b - LD $19.60 N/A $18.81
Natural Gas
Replacement
WWTP Alt. 3 - ND $7.70 N/A $24.11
Alt. 3 - 1500 Div $9.70 N/A $32.25
Alt. 3 - LD $39.80 N/A $82.77
Expanded
Composting
Compost Alt. 4 $5.70 N/A $15.69
City of Iowa City | CAAP Methane Recovery Feasibility Study
Appendix B - Memo | Financial Proforma - Breakeven Analysis
5
In general, pipeline injection and electricity generation at the landfill are the only options that
generate enough revenues to pay for the operating costs on an ongoing basis. Pipeline injection
is feasible with bonding terms of about 18 years, while electricity generation would require
around $19 million in grant funding support to be financially viable within 30 years. That said,
the electricity generation revenues are currently limited by the net metering and buyback
agreements in place. This analysis has assumed that MidAmerican Energy Company (which
provides electricity to the Iowa City Landfill) will negotiate a buyback agreement similar to the
LMP-based rates they offer under their net metering agreement. However, if the City were able
to negotiate a higher rate, it could make the alternatives financially viable. Specifically, an
electricity sales rate of 5.7¢ per kWh would make all three of the alternatives financially viable
within the 30-year time frame.
Grant Funding
A few federal and state grant programs could potentially be leveraged to reduce the City’s
financial contribution and make the alternatives financially viable. The table below summarizes a
few options based on literature review of the biggest programs which have had funding cycles
within the past year.
Table 4: Grant Funding Opportunities
Program
Administrator
Funding
Program
Eligible
Applicants Eligibility Requirements Funding
Federal Programs
US Department
of Energy
Office of Energy
Efficiency and
Renewable
Energy
Bioenergy
Technologies
Multi-Topic
FOA
Individuals,
entities, state
or local
governments,
corporations,
etc.
Varies based on year. FY2020
included area of Waste to Energy
Strategies for the Bioeconomy,
focusing on projects addressing
topics such as advanced
preprocessing of feedstocks,
conversion of wet wastes to energy
and products, and synergistic
integration of algal biomass
technologies with municipal
wastewater treatment for greater
energy efficiencies and lower costs.
20% cost share required.
Varies based on
topic. Based on the
FY20 grant
application
documentation,
minimum award was
$1,000,000 and
maximum award for
most topics was
between $2,000,000
and $4,000,000.
US Department
of Agriculture
Biorefinery,
Renewable
Chemical,
and Biobased
Product
Manufacturing
Assistance
Program
Individuals,
entities, state
or local
governments,
corporations,
institutions,
public power
entities, etc.
Must be for development and
construction or retrofitting of a
commercial scale biorefinery using an
eligible technology for the production
of advanced biofuels and biobased
products. Majority of production must
be an advanced biofuel.
Maximum loan
guarantee of 80% of
project costs or $250
million. Term length
of the lesser of 20
years or the useful life
of the project.
State Programs
Iowa Energy
Center
Iowa Energy
Center Grant
Iowa
businesses,
colleges and
universities,
and private
nonprofit
agencies and
foundations
Projects must provide benefit to Iowa
ratepayers and aid in one of the key
focus areas of the Iowa Energy Plan:
1) technology-based research and
development, 2) energy workforce
development, 3) support for rural and
underserved areas, 4) biomass
conversion, 5) natural gas expansion
in underserved areas, 6) electric grid
Minimum award of
$10,000, maximum
award of $1,000,000.
City of Iowa City | CAAP Methane Recovery Feasibility Study
Appendix B - Memo | Financial Proforma - Breakeven Analysis
6
Program
Administrator
Funding
Program
Eligible
Applicants Eligibility Requirements Funding
modernization, 7) alternative fuel
vehicles.
Iowa Energy
Center
Alternate
Energy
Revolving
Loan Program
Businesses,
individuals,
water and
wastewater
utilities, rural
water districts
and sanitary
districts
Eligible technologies and resources
include solar, wind, waste
management, resource recovery,
refuse-derived fuel, agricultural crops
and residue, and wood burning,
hydroelectric facility at a dam, energy
storage, anerobic digestion, biogas,
combined heat and power, wind
repower. Facility must be in Iowa and
be wholly owned by the borrower.
Minimum loan of
$25,000, up to 50%
of eligible project
costs. Maximum loan
of $1,000,000 per
project. Loans offered
at 0% interest.
Iowa
Department of
Natural
Resources
Solid Waste
Alternatives
Program
Any unit of
local
government,
public or
private group,
or individual
Projects to reduce the amount of solid
waste generated and landfilled in
Iowa. Funds can be used for waste
reduction equipment and installation,
recycling, collection, processing or
hauling equipment, purchase and
installation of recycled content
products. 25% cash match required.
First $10,000 is
eligible as a
forgivable loan, next
$50,000 is eligible as
a zero-interest loan,
and 3% loan on the
remainder.
Date: December 28, 2020
To: Climate Action Commission
From: Ashley Monroe, Assistant City Manager
Re: Methane Feasibility Study Documents
At the January 4, 2021 Climate Action Commission meeting, HDR will be presenting the results
of the Methane Feasibility Study conducted in 2019 and 2020. This study was conducted to
meet the Climate Action and Adaptation Plan initiatives 3.7 and 3.8. (https://www8.iowa-
city.org/weblink/0/edoc/1803121/Climate%20Action%20Plan.pdf). Two of the resulting reports,
Feasibility Report and Facility Evaluation provide good overviews of the project and are
provided for your reference in this packet.
The HDR team evaluated current and future biogas generation potential and identified
alternatives for utilizing biogas at the Iowa City Wastewater Treatment Plant (WWTP) and/or the
Landfill and Recycling Center (Landfill). HDR used its Sustainable Return on Investment (SROI)
process to measure the feasibility of the objectives. The study was based on three categories
for feasibility: net greenhouse gas emissions; net energy impact; and economics. Three
alternatives were evaluated at each facility with three different scenarios for diversion of organic
wastes from the Landfill. These study parameters led to seventy different combinations of
alternatives and scenarios between the two facilities, of which, they will present an overview of
the project and highlight top recommendations. HDR will present their findings and be available
for questions in order to assist the Commission, City Council, staff, and other interested parties
with any next steps.
If you have specific questions, Joseph Welter, Senior Civil Engineer, managed this project and
has offered his contact information. Please feel free to email or call Joe at joe-welter@iowa-
city.org and 319-356-5144.
Outreach Working Group, Meeting Agenda
Wednesday, Jan. 27, 2020, noon – 1 p.m.
Zoom Meeting Link:
https://zoom.us/j/97398387268?pwd=Mmo2a1A0T1E2MytqU0Zia2Uxa3FHZz09
Members:
Sarah Gardner, Matt Krieger, Madeleine Bradley, Grace Holbrook, Marcia Bollinger, Deb
Schoelerman
Guests:
Bob Opplinger, Tom Banta, Audrey Wiedemeier, Liz Hubing, Cara Hamann
1. Welcome and Introductions
2. Updates
• Ambassador program: The next training session is set to start on Feb. 3 and run
through March 24. This cohort was drawn from the waitlist of previous applicants.
The application portal will reopen in March to recruit trainees for the third cohort,
which is scheduled to begin training in April.
• Marketing RFP: Negotiations are nearing completion with the preferred firm as to
the scope of work and final contract, which will be brought before Council in
February for approval. In the meantime, staff is compiling communications and
marketing collateral for a comprehensive review as the first start of the project
when it gets underway.
3. Discussion of active transportation community outreach ideas presented by Bob
Opplinger (see attached document): Bob Opplinger began by giving highlights of the
attached list noting that many programs are already in existance. Liz Hubing provided
some details of the Bike Friendly Business program and suggested there might be a
volunteer opportunity connected with it for the Climate Ambassadors. Audrey
Wiedemeier discussed upcoming programming with the Bike Library, including a “Raise
It Up” series of four family-friendly routes. The routes include 4-5 stops that are
significant to the Black community in Iowa City. A self-guided audio tour narrated by
Black community leaders will allow participants to learn more at each stop. The goal is to
have 200 people per month participate in the rides. Weidemeier raised concerns she has
had about putting together events meant for a crowd. Marcia Bollinger and Sarah
Gardner shared conversations they had had with the Parks & Rec department on this
topic, saying it plans are in the works for summer events like Party in the Parks, but they
are being designed in a way to allow attendees to social distance. Opportunities for
collaboration were discussed, including promoting the Raise It Up events in the
Sustainability Newsletter. Gardner said she would share information with Wiedemeier
about the Climate Action Grants as a potential funding opportunity for the program.
Hubing said she would connect with Gardner to discuss a potential collaboration on the
Bike Friendly Business program as well. Opplinger said he would send information on
Bike to Work Month. Wiedemeier shared that the Bike Library has secured a new
location at 1222 S. Gilbert Court and has plans for a celebration of the relocation later
this month.
4. Other Items
Next Meeting Wed, 3/17
Active Transportation Community Outreach Ideas (from Bob Opplinger)
1. Create an active transportation advisory committee and/or hire an active transportation
coordinator. This is long overdue. The advisory committee or coordinator would work with IC
transit services, neighboring communities, and Johnson county as well as the MPO.
2. Promote more widely the Bike to Work Month activities. There will be a dozen or more
events. The calendar is just being put together.
3. Work with the schools to promote Safe Routes to Schools. This is a nationally funded
project to promote active transportation to schools. The Iowa Bike Coalition has a staff person
dedicated to promoting this and will host their annual, virtual workshop for it on Thursday,
January 28. (It’s FREE.) The IC South District and the Bike Library were ramping up a biking
version last spring. Garner school in NL has promoted this idea too and maybe Longfellow.
4. Help promote IC South Districts ambitious schedule of biking actives. Because of all the
trails, ICSD want to become the biking mecca of IC.
5. Assuming live farmer’s markets resumes, more actively promote Move Naturally to the
Market. This promotion goes back to the Blue Zones Project and was hosted by BIC in May.
People who biked or walked to the Saturday market received a $2 coupon for the market.
(Vendors were reimbursed at the end of each market.) It was well received by vendors as well
as patrons and attracted up to 250 people on a sunny Saturday.
6. Promote more widely, the League of American Bicyclists Bike Friendly Business initiative.
This is a companion program with the Bike Friendly Community & Bike Friendly University
programs. Our metro area has about a dozen BFBs. Tom Banta and I were able to persuade
about 6-8 area business/worksites to apply. (It does not require everyone in the workplace to
ride a bike to work.) IC Civic Center, Robert Lee Rec Center & Public Library collectively hold a
silver-level designation, Johnson County offices a gold-level and we have one platinum-level
business.
7. Develop a promotion that rewards bikers or walkers patronizing local businesses. There is a
national program Bike Benefits (bb2.bicyclebenefits.org), that offers specified discounts, e.g.
10% off purchases, for patrons who bike to their business sporting the program’s decal.
8. Learn to Bike classes. Work with BIC and IC rec services to set-up classes. We can teach
an adult to ride a bike in 2-3 hours. NYC hosts clinics around town and annually teaches about
30K new bikers. Young kids take a little longer. We should have available soon a short
pamphlet “Teaching your Child to Ride a Bike; A Guide for Parents and Caregivers.”
9. Street Biking Classes. Street biking would take proficient riders further in offering them help
to gain confidence using bike lanes and “safe streets” to commute.
10. Create a promotion that runs through the summer. For example, Iowa City Active
Transportation Challenge. Beginning in May and running thru September create a challenge like
the National Bike Challenge (https://www.lovetoride.net/usa). In its simplest form, a person who
walks or bikes to work or on an errand instead by car would receive a credit. Accumulate 20
credits and receive a $10 gift card for area businesses. This is an ambitious idea. Some things
to workout.
a. The threshold for the number of points to receive a gift card. Twenty equals about
one/week and the size of the reward
b. How to record points. Is honesty an issue; considering the reward amount, I’d say
no.
c. How to underwrite expenses. Maybe offer only 500 cards and the number of gift
cards an individual can receive, e.g. two. The biking community would offer financial
support.
d. Soliciting cooperation with area businesses. These days I don’t think that’d be hard.
e. Could you offer weekly super “raffle prizes” to people enrolled, e.g. a gift certificate
to Film Scene.
f. Promotion
Building Working Group Report
For Climate Action Commission Feb. 1, 2021 packet
Residential Energy Data
The Building Working Group, including CAC members (Matt, Ben, Becky) and community volunteer
member (Jeff), have talked with MidAmerican Energy contacts and/or discussed re getting residential
energy data at the smallest level possible.
• Goal : To understand potential areas to prioritize for energy efficiency and related
improvement.
• Create a map to show areas of high residential energy use and based on differences
seen use that info for programming and outreach. Energy outreach programs are often
most effective when done on a block by block or other small neighborhood scale versus
one house here and one house there.
• When the city’s Energy Analyst is on board, the BWG would like to move quickly to set
up a meeting with that person and other city staff and move forward with requesting
energy data and using it to support related climate actions.
• In particular, understanding residential energy data would help support these
Accelerated Actions:
o BE-1 Promote energy efficiency;
o BE-2 Partner with stakeholders to promote green buildings and rehabilitation;
o BE-3 re energy info in MLS listings
o BI-1 re home energy assessments
o BI-3 re neighborhood energy blitzes
o BR-5 re rental energy efficiency
o BPP-2 net-zero public housing
• Note: the data ideally should be made publicly available so others can do their own
analysis, especially GIS-based.