The report found that the addition of storage technologies to a solar installation has the potential to nearly double stand-alone solar electricity bill savings at about a third of the cost of solar. For example, the report said that the addition of a $112,100 battery storage system to a $385,000 solar installation increased savings from $15,000 per year to $27,900 — an 85 percent increase. In addition, the report determined that solar plus storage projects result in a significantly shorter payback period than stand-alone solar projects.
The Clean Energy Group, California Housing Partnership, Center for Sustainable Energy and software provider Growing Energy Labs Inc. prepared the report — Closing the California Clean Energy Divide — which was released last week.
The report highlights the value of solar plus storage in the context of California’s Multifamily Affordable Housing Solar Roofs program, which was established with the signing last fall of California Assembly Bill 693. The 10-year program supports the deployment of solar systems in affordable multifamily rental housing. It will be funded through cap-and-trade proceeds and provide up to $1 billion in funding.
According to the report, the California Public Utilities Commission will establish rules for the solar roofs program through a public proceeding.
“As the proceeding gets underway, a key question is whether it makes economic sense for state policy to encourage solar plus storage technologies in affordable multifamily rental housing now and provide the incentive and policy structure to encourage those installations,” the report said.
The report outlined additional challenges that must be addressed in the move to deploy storage with solar installations at affordable housing properties, including:
- demonstrating that property owners can make a financially sound investment in solar plus storage technologies
- structuring an incentive program that provides for an integrated, inclusive mitigation package that includes efficiency, solar, and energy storage for the benefit of low-income tenants and owners of affordable rental housing properties alike
- making the case for the value of storage under likely future California solar policies and utility rate structures
The group will release two additional reports to help stakeholders to address these challenges.
Lead image credit: Clean Energy Group.