Speaker: Kenneth Gillingham is an Assistant Professor of Economics at Yale University. More »
Abstract: An extensive literature points to the importance of social interactions in influencing economic outcomes. We examine a set of natural field experiments on a rapidly expanding behavioral intervention designed to actively leverage social learning and peer interactions to promote solar photovoltaic technology in Connecticut. The "Solarize" program involves a municipality-chosen solar installer, group pricing, and an informational campaign driven by volunteer ambassadors. We show that the program is remarkably effective: a treatment effect increasing installations by 27 per municipality on average, increasing installations by over 100 percent. The program also lowers installation prices, an effect that spills over to adjacent block groups. When municipalities are chosen randomly, the treatment effect is roughly half. However, this still exceeds the treatment effect from a program run by a single installer without competitive bidding. Calculations reveal that the Solarize program is cost-effective and social welfare-improving. Survey results illuminate the mechanisms underlying our findings.