At a Glance



Project Type

Clean and Renewable Energy




Philadelphia, PA

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Net Present Value:


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Annual kWh Savings:

2,400,000 kWh

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Annual CO2 Reductions:

1,400 metric tons


Caitlin Trethewy identified investment grade opportunities at Comcast’s network facilities and theme parks, building on new business opportunities and prior strategic development.


The Comcast Sustainability Team endeavored to create the strongest possible business case for the installation of photovoltaic (PV) systems at company properties to reduce carbon emissions and the use of grid electricity. Procuring these systems on a nationwide basis, at a price where they are competitive with existing commercial electricity tariffs can be challenging. EDF Climate Corps fellow Caitlin Trethewy joined the newly established Office of Sustainability and Environmental Affairs to test out its strategy and create the business cases for on-site rooftop and ground mount systems.  


Trethewy aggregated site suggestions to determine financial feasibility from each business unit within Comcast.  She leveraged an earlier analysis that identified attractive sites based on electricity price, solar resource and various local state policy incentives, and came up with a shortlist of 30 sites. The next step was to assess both the shortlist based on physical components, system sizing and electricity billing data, as well as relevant policy incentives in the specific states and municipalities under consideration. The sites were prioritized based on interest rate sensitivity analysis and cost avoidance derived from onsite PV systems using a financial model she built. Since procuring solar systems for small sites in bulk can reduce costs, Trethewy identified 11 smaller-scale sites where solar system will have the strongest net present value.

Potential Impact

Trethewy recommended 5 large sites for onsite commercial solar, yielding annual savings of $280,000, a net present value of $630,000, at an 8% discount rate, and an annual reduction of 1380 metric tons of CO2. The financial analysis was successfully used to secure significant funding during the 2018 budget process. Trethewy provided key practical advice on renewable energy procurement and injected the ability to successfully navigate engineering challenges.

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