Energy transitions of declining energy industries: the effect of renewable portfolio standards on the U.S. coal industry

This study examines the influence of renewable portfolio standards (RPS) on coal industry employment and wages in the top 10 U.S. coal-producing states from 2001 to 2018, with a specific focus on the 2003–2009 RPS adoption period. Employing a difference-in-differences methodology and utilizing data encompassing employment, gas prices, and RPS-related MWh at the quarterly level, our findings reveal that RPS had only temporary and minor adverse effects on coal employment. These effects manifested with a delay of up to four quarters but dissipated within two years. Moreover, RPS had no significant impact on state’s coal sector wages.