Electric utility plans are consistent with Renewable Portfolio Standards and Clean Energy Standards in most US states

Abstract

Electricity is one of the easiest—and therefore most urgent—sectors to decarbonize. In the USA, state-level Renewable Portfolio Standards (RPS) and Clean Energy Standards (CES) are key policy tools pursuant to this objective. These policies mandate that electric utilities achieve specified renewable compositions on specified timelines. In recent US history, electricity has been decarbonizing faster than major agencies predicted, which raises the question of whether utilities are decarbonizing faster than RPS and CES targets prescribe. We address this question by comparing state-level RPS and CES targets to historical progress and stated decarbonization targets from 220 utilities, comprising at least 52% of sales in every state and 76% of sales on average. In 18 of 26 states with current RPS or CES and 9 of 11 states with expired RPS or CES, utilities’ generation and targets meet, nearly meet, or exceed state targets. We project that utility targets and linear progress thereafter put six states without current RPS or CES on track for over 90% renewable electricity by 2050, and they put US electricity on track to reach 100% renewable by 2060. Including nuclear—unlike most RPS and CES policies—makes these results starker: utilities’ past and planned generation meets or exceeds 31 of 37 state targets, 14 states without RPS or CES would decarbonize electricity by 2050, and US electricity would also decarbonize by 2050. Our results suggest that electric utility plans are mostly consistent with state-level targets but are behind the Biden administration’s target of decarbonizing electricity by 2035.