New research explores disparities in US rooftop solar deployment

January 10, 2019

In a new paper in Nature Sustainability, BIDS Senior Fellow Dan Kammen, former BIDS Data Science Fellow Deborah Sunter, and UC Berkeley researcher Sergio Castellanos investigate rooftop solar photovoltaics (PV) deployment across the US, and explore disparities in its adoption based on race and ethnicity.

Using imaging data collected through Google's Project Sunroof and demographic information available through the US Census Bureau's American Community Survey, the team compared the relative adoption of rooftop PV across census tracts grouped by racial and ethnic majority. Despite improvements in public policies and access to alternative financing mechanisms in recent years, the research team discovered that significant disparities exist in rooftop solar deployment across the country, and that the benefits of solar power are not accruing equally to all individuals and communities. “Advances in remote sensing and in ‘big data’ science enable us not only to take a unique look at where solar is deployed but also to combine that with census and demographic data to chart who gets to benefit from the solar energy revolution,” said Sergio Castellanos, a faculty member at UC Berkeley’s Energy and Resources Group and the California Institute for Energy and Environment (CIEE). “This information allows us to think more deeply about the effectiveness of current policies and approaches to accelerating solar PV (photovoltaics) deployment.”

In order to maximize the potential of solar power and prevent disparities from growing, the team argues for the development of more effective and inclusive energy policies, and encourages more specialized government interventions, expanded benefits and incentive programs, and more adaptive business models. “Solar power is crucial to meeting the climate goals presented by the Intergovernmental Panel on Climate Change, but we can and need to deploy solar more broadly so that it benefits all people, regardless of race and ethnicity,” said Deborah Sunter, PhD, currently a professor of mechanical engineering at Tufts University, and the study’s lead author. 

"The Green New Deal and other environmental justice efforts can use our findings to build a better and more inclusive energy transition,” said Dan Kammen, who is the chair of UC Berkeley's Energy and Resources Group, a professor in the Goldman School of Public Policy, the director of the Renewable and Appropriate Energy Laboratory, and a former Science Envoy for the U.S. State Department. “Our work illustrates that while solar can be a powerful tool for climate protection and social equity, a lack of access or a lack of outreach to all segments of society can dramatically weaken the social benefit.” 

The data for this study can be found on the web at Kammen’s Renewable and Appropriate Energy Laboratory.


Related Articles

Disparities in rooftop photovoltaics deployment in the United States by race and ethnicity
January 10, 2019  |  Deborah A. Sunter, Sergio Castellanos & Daniel M. Kammen  |  Nature Sustainability

Who benefits from the solar energy revolution?
January 10, 2019  |  Kara Manke  |  Berkeley News

Racial inequality in the deployment of rooftop solar energy in the US 
January 10, 2019  |  Kalimah Redd Knight  |  TuftsNow

Solar Power’s Benefits Don’t Shine Equally on Everyone
April 4, 2019  |  Jeremy Hsu  |  Scientific American


Featured Fellows

Deborah Sunter

Energy & Resources Group

Daniel Kammen

Energy and Resources Group, Goldman School of Public Policy, UC Berkeley
Faculty Affiliate