Monday, November 13, 2023
10:30 AM - 12:00 PM
The Role of Peer Influence in Low-Income Rooftop Solar Adoption
Session ID
B1 - Why We Decarbonize (Or Don't)
Social Science Insights
Eric O'Shaughnessy

Early rooftop solar photovoltaic (PV) adopters can influence other households to adopt. To date, these so-called peer effects have disproportionately driven PV adoption among relatively affluent households. A growing chorus of stakeholders are, however, calling for measures to increase PV adoption equity by driving more low-income PV adoption. Here, we build on previous peer effects research by using household-level income estimates to explore how peer effects drive low-income PV adoption. We used refined versions of previous models to estimate peer effects as a function of local PV adoption and installation rates. We reach three primary conclusions. First, we find evidence of peer effects at all income levels, including among low-income households. The magnitudes of our estimated peer effects are largely in line with previous estimates. Second, we find that peer effects are generally weaker among low-income households (see Fig. 1). This result partly reflects the fact that low-income households are less likely to adopt PV in general, and that peer effects models do not control for pre-existing differences in adoption propensities. Third, we find that peer effects are stronger within than across income groups (see Fig. 2). For instance, our results suggest that installations on low-income households exert around twice as strong of an influence on low-income adoption decisions compared to installations on more affluent households. Relatively strong, within-group peer effects provide a rationale for policies to support low-income adoption by seeding installations in low-income areas. At the same time, any impacts of such seeding policies would be mitigated by the relatively weaker impacts of low-income peer effects. An effective approach could be to couple low-income seeding with other interventions to reduce barriers to low-income adoption, such as incentives.

Supporting Document 1