Having identified the available options, evaluate those opportunities against your city’s goals and priorities. Below is a list of considerations that may be useful in comparing the various options.
Short-List and Prioritize Specific Renewable Energy Initiatives
Some forms of renewable energy can be procured more quickly and easily than others due to the varying complexity of the necessary transactions. An EPA analysis summarizes the range of complexity as follows:
Different models will have different minimum and maximum size thresholds or other constraints that you should consider with respect to your goals.
Green TariffsVaries by program; typically limited to large commercial customers.
On-Site Self GenerationAverage size for commercial solar photovoltaic (PV) systems was 181 kilowatts (kW) in California in 2017.
Community SolarProjects typically range from 50 kW to 2 megawatts (MW) in size, but can be larger.
Physical Power Purchase AgreementsProject sizes can range from ~10 MW up to hundreds of MWs.
Virtual Power Purchase AgreementsProject sizes can range from ~10 MW up to hundreds of MWs.
The EPA’s AVERT tool can help quantify the potential GHG and air pollution impact of various renewable energy or energy efficiency projects.
Local Economic Impact
NREL’s Jobs and Economic Development Impacts (JEDI) models provide estimates of the economic impact of various renewable energy projects. While the solar PV model is no longer officially supported, it is available upon request.
Financial Costs and Benefits
The World Bank’s CURB tool may help you evaluate the potential cost and impact of different projects and programs. In addition, when evaluating potential costs, you may want to consider both whether the city has funds budgeted to directly purchase and own required assets and what consultant budget may be required.
A variety of renewable energy programs can support social equity by, for example, adopting inclusive contracting principals. Such principals will inform: what firms are encouraged to bid, proposal evaluation criteria, the diversity of the respondents’ leadership and that of the evaluation committee, the use of local suppliers and a local workforce, and the location of the specific renewable energy projects. Cities can also ask for or require local job training or hiring programs in their RFPs. To date, community solar has so far provided the most straightforward option for cities to address inequity while also supporting renewable energy. In some cities, local housing authorities may be able to install or utilize on-site or community solar projects to provide low-income residents with low-cost, renewable electricity. NREL’s Solar for All tool may help you identify public housing locations and more generally evaluate the socioeconomic implications of site-specific decisions.
Renewable energy projects that are located within the community, such as community solar and on-site solar, can potentially be paired with energy storage and microgrids to enhance local grid resilience. Generally speaking, off-site projects are not able to provide these resilience opportunities to local communities.
Leadership in Advancing a Clean Economy
Partnering with other entities to jointly procure energy may allow you to improve the size and visibility of your efforts. Additionally, the larger or more unusual your transactions, the more media attention you are likely to garner.