A Rooftop Revolution? A Multidisciplinary Analysis of State-Level Residential Solar Programs in New Jersey and Massachusetts

The success of alternative energy policies is usually measured in terms of energy capacity. By this metric, statelevel policies to promote solar installations in New Jersey and Massachusetts have been a success. To fully evaluate these policies, however, it is necessary to consider how these policy programs are structured and funded, who participates in these programs, and the complete life-cycle consequences of ‘clean’ energy technologies. This paper focuses specifically on residential solar installations, which represent more than half of the total U.S. rooftop solar capacity potential. It takes a multidisciplinary approach that draws on policy analysis, spatial and demographic analyses, and life-cycle assessment. The analyses reveal three key conclusions: First, state-level policies have shifted from subsidies for solar installations to incentive-based support based on system performance, which have reduced the payback period for residential solar to less than ten years and have contributed to the growth of thirdparty leasing companies. Second, communities with low median income and/or a high percentage of non-white residents generally remain at lower than expected levels of participation. Third, while residential solar installations significantly offset greenhouse gas emissions and compounds that harm human respiratory health after 18 months, switching to photovoltaic panels generates a net increase in the production ecotoxic chemicals. Drawing on these observations we recommend policy changes to encourage broader geographic and demographic participation, to recognize the importance of solar leasing companies and landlords, and to promote the use of solar panels with lower environmental impacts across the lifecycle.