Proposed Business Case: Public Developer Model

CTA Maintenance Facility & Rail Yard

The Chicago Transit Authority Heavy Maintenance Facility & Rail Yard in Skokie houses multiple shops on more than 30 acres.  Rail lines connecting the site to the CTA system limit the possibility of ground mounted PV. However, the building has more than 400,000 sf of roof space and significant parking lots.

The proposed community solar system installation would utilize nearly the entire roof to host 1,128 kW of rooftop solar and 772 kW in solar parking canopies to be installed at the north and south lots. This proposed business case is a developer-owned model, with the CTA as an anchor subscriber, and the remainder of subscribers coming from households and businesses from the surrounding community.

Community Solar

Community solar is a solar photovoltaic (PV) installation that provides energy, financial benefits, or both to multiple participants. Participants, also called Subscribers, can buy or lease a share of the community solar installation and receive credits on their electricity bill for the power generated by that share. Subscribers can be households, businesses or anyone with an electric bill.

System Design

The proposed design incorporates roof-mounted arrays along with parking lot canopies. The proposed system uses 325-watt panels in a layout that takes advantage of most of the available flat roof space in a non-penetrating, ballasted racking system. The design also uses parking canopies in small enough proportion to ensure overall costs remain as close to $2 per watt as possible - they are anticipated to be $2.06 per watt overall. This maximizes output and maintains a competitive cost.

Business Model

Developer-owned, host-owned and Equity Investor models were analyzed.  The equity-investor model did not produce a necessary return. While the host-owned system produced a better overall Net Benefit over the life of the system, the return was not good. The developer-owned system produced a good return for both developer and host and allowed no upfront investment or risk for the host site. Developer IRR for this proposed model is anticipated to be 10% and the host site average annual return over $19k.

Solar Developer/System Owner Metrics

25-Year Costs…………………………………………..   ($5,436,598)

25-Year Revenues……………………………………   $6,826,652

25-Year Net Benefits……………………………….   $1,390,054

25-Year Net Present Value (NPV)…………….   $180,194

Return On Investment (ROI)……………………   25.6%

Payback Period…………………………………….….   4.2 years

Internal Rate of Return (IRR)……………….....   9.9%     

SREC Value (1 MW-2 MW Block)…………….    $45.00/MWh*

SREC Adder Value-100% Low-Income.…….   $0

Host Site Metrics: Leasing Site & Anchor Subscription

25-Year Costs…………………………………………..   ($778,708)

25-Year Revenues……………………………………   $1,256,103

25-Year Net Benefits……………………………….   $477,395

Upfront Investment/Financing……………..…  $0

Net Year 1 Savings/Revenue…………………...  $8,078

Average Annual Revenue over 25 years….   $19,096

SREC Value (1 MW-2 MW Block)…………….    $45.00/MWh*

SREC Adder Value-100% Low-Income.…….   $0

*All SREC and SREC Adder values are assumptions. See Overview for more details

Documents

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