What Rooftop Solar Tells Us About Who’s Participating (And Who Is Not) In The Clean Energy Transition

Energy Innovation partners with the independent nonprofit Aspen Global Change Institute (AGCI) to provide climate and energy research updates. The research synopsis below comes from Dr. James Arnott , Executive Director at AGCI, and a full list of AGCI’s quarterly research updates covering recent climate change research on clean energy pathways is available online at https://www.agci.org/solutions/quarterly-research-reviews
Moving society to near zero carbon emissions will entail a substantial amount of distributed clean energy generation. Distributed generation can occur at household or neighborhood scales, such as through rooftop solar photovoltaic (PV) panels. A recent feasibility analysis by Project Drawdown estimated that distributed PV generation could compose nearly 40 percent of all solar PV production in a zero emission energy system.
As important as this direct contribution of distributed PV may be, adoption patterns of carbon-free technology also illustrates important social dynamics that influence the speed and scale of energy transitions. Knowing who is—or is not—participating in the adoption of cleaner energy sources can help guide more effective policy and communication strategies. For example, commonalities in participation across different groups of people may help to justify and expand strategies that are shown to work well in many contexts. On the other hand, disparities in participation reveal underlying problems where targeted interventions may be required to ensure a just, equitable energy transition is achieved.
Recent analyses of rooftop solar adoption across the United States illuminate good and bad news. Consider two studies making use of a nifty dataset of rooftop solar deployment from Google’s Project Sunroof . Against the backdrop of today’s acute partisan division, one study finds encouraging evidence of ideological diversity among solar adopters. However, a second study provides a more worrisome outlook in terms of disparate adoption rates between racial groups.

Figure 1 presents the proportion of registered Democrats and Republicans among households of solar adopters and neighboring control households where no solar adoption has occurred. Note this data features sampled households in states where party registration data is available. The full text of the study also uses a different dataset for sampled locations in states where this data is not available, but it finds similar results.

The first study led by Matto Mildenburger, a political scientist at University of California Santa Barbara is titled, Households with solar installations are ideologically diverse and more politically active than their neighbors. The authors use Google’s household level data alongside individual partisanship and voter participation datasets, which are linked to randomly selected samples of households distributed across the U.S. One sample contained about 4,100 households...