Low-Income and Elderly with Feed-in Tariffs Drive Solar Installation Rates for Energy Equity

Abstract

Abstract Australian residents have the highest solar energy installation rate in the world. However, after experiencing rapid growth, the residential installation rate began to decline sharply starting in 2011. In this study, we examine installation data for small and medium-sized solar photovoltaic (PV) devices across 2,413 Australian postcode areas using regression analysis and coarsened exact matching (CEM). We reevaluate four primary factors influencing the residential solar energy installation rate: natural factors, energy policy factors, rooftop space factors, and socioeconomic factors. Our findings reveal that areas with higher proportions of elderly or low-income residents exhibit greater household solar PV installation rates. Additionally, increased feed-in tariff (FiT) subsidies further motivate these resident groups to install solar PV systems, resulting in higher installation rates within their neighborhoods. The results also suggest that if a subsidy policy with a feed-in tariff average expected return (FiT-AER) of more than 7 cents/kWh persists, elderly and low-income groups in Australia may continue to dominate home solar PV installations. This trend could potentially mitigate energy inequity during the energy transition process.