Installing inequality: the racial disparities in solar deployment

By Deborah Sunter (Tufts University), Sergio Castellanos and Prof Daniel Kammen (University of California, Berkeley)


Unequal access to clean energy

Unfortunately, this growth has not benefited everyone equally. We recently published a study in Nature Sustainability with a worrying trend: there are racial disparities found in rooftop solar PV deployment in the United States.

What the data says

We leveraged a collaborative effort with Google’s Project Sunroof team, who map rooftop solar PV potential across 60 million rooftops in the United States. Combining Google’s Project Sunroof’s location of existing rooftop solar installations across the U.S. with demographic data such as household income, homeownership, and ethnicity and race, from the U.S. Census Bureau’s American Community Survey, we were able to explore trends across census tracts with and without solar rooftop PV installed while controlling for median household income.

We present here the three most revealing elements of our findings.

1. For the same household income, black-majority census tracts — or neighbourhoods — have installed up to 69% less rooftop PV than no-majority census tracts (neighbourhoods where no single race or ethnicity makes up the majority). Hispanic-majority census tracts have installed up to 30% less rooftop PV than no-majority census tracts. Meanwhile, white-majority census tracts have installed 21% more rooftop PV than no-majority census tracts.

47% of black neighbourhoods had no existing rooftop solar systems versus 21% of white neighbourhoods. 47% of black neighbourhoods had no existing rooftop solar systems versus 21% of white neighbourhoods.

 

47% of black neighbourhoods had no existing rooftop solar systems versus 21% of white neighbourhoods. 47% of black neighbourhoods had no existing rooftop solar systems versus 21% of white neighbourhoods.
Percentages of each census tract with and without existing rooftop photovoltaic installations. In the census tracts listed, at least 50% of the population self-identified as a single race or ethnicity.*

 

The need for more inclusive energy infrastructure policy

Plenty of questions still remain open, for example, how has a systematic disparity developed? Have approaches from NGOs focused on certain demographics been successful in recent years? Our project identifies this inequality and does so in a given point in time. We recognise the urgency to conduct more research to help determine the root causes of the differences and track the evolution of policy interventions over time. However, already these findings can be useful in developing better and more inclusive energy infrastructure policy and outcomes, including as part of the evolving ‘Green New Deal’, and programs at the state and federal level.



This piece is also available on our Medium page.