It used to be rare to see solar panels shining from residential rooftops, but in the last two years the sight has become much more common. As solar installations have doubled, installations are increasingly located in predominantly moderate-income neighborhoods. This demographic shift was what was intended when the California Solar Initiative (CSI), a state incentive program designed to create a solar market, started more than ten years ago. In this regard the program has been a success – effective and with bipartisan support from California’s past two governors resulting in 3451 megawatts (MW) of solar.
Using CSI and investor-owned utility interconnection data, we associated the zip code of the solar installation with the median owner-occupied income associated with the same zip code. Since 2014, 59% of residential solar installations were in zip codes with median incomes of $40,000 – $70,000 per year.