A flexible approach to meeting zero net energy goals could benefit consumers and the environment, according to research conducted by The Brattle Group and released by the National Rural Electric Cooperative Association (NRECA) and the Natural Resources Defense Council (NRDC).
ZNE homes are designed to produce as much energy from clean on-site energy sources as they consume each year.
The research compares two approaches to meeting a ZNE goal for new housing developments: Requiring solar power installations on each home to offset annual electricity use or a community solar program in which homeowners receive a share of a combined solar array.
The analysis produced the following findings:
· The economies of scale and technological advantages of community solar for new housing in non-urban areas would provide roughly 13 percent lower total solar project costs per watt of electricity generated than ZNE homes, and a 25 to 30 percent greater annual energy output than ZNE homes.
· A community solar approach to ZNE could serve a 200-home development with a total project cost savings of about 30 to 35 percent relative to conventional ZNE configurations. Looked at another way, for the same amount of money, a community solar array yields an additional 40 to 45 percent carbon emission savings over individual rooftop installations.
“This research suggests that when we take a more expansive and flexible approach to reducing carbon emissions and residential development, both consumers and the environment can win,” said Keith Dennis, principal for end-use energy efficiency at NRECA.
“The study points to a good policy option to reduce the costs of meeting a Zero Net Energy goal. For utilities and solar developers moving forward, partnering with housing developers may serve as a new business model for community solar projects,” said Dylan Sullivan, senior scientist for the Natural Resources Defense Council. “For community solar to be a viable option in meeting a building code like California’s, homeowners, builders, and code officials will need assurance that the community solar project serves the building for the long-term.”
“There are a lot of opportunities to improve the way we generate and consume electricity,” said Ryan Hledik, a principal at The Brattle Group and co-author of the study. “Our study highlights how a systems-oriented approach can both increase the benefits and reduce the costs of emerging energy policies.”
The research uses publicly available data from the National Renewable Energy Laboratory (NREL) to compare economic benefits and CO2 emissions reductions for residential development in Minnesota and New Mexico.