Addressing climate change requires societies to transition their electricity infrastructure from fossil fuels towards renewable energy resources. To foster this transition, governments have passed policies that incentivize low-carbon technologies, including wind, solar and geothermal. In the United States, 37 states have passed renewable portfolio standards (RPS), creating goals for electricity’s share of renewables. Dozens of states have also instituted net-metering (NEM) policies, compensating individuals and organizations that supply distributed energy to the grid. Initially, these policies passed with bi-partisan support buttressed by favorable public opinion.

However, the past ten years have seen renewables policies become increasingly politicized. Across US states, several groups have sought to repeal RPS policies and impose large, monthly charges on NEM customers. Given that technologies require stability to drive investment and reduce costs, these developments are particularly concerning. This research asks: what are the mechanisms through which actors support or undermine renewables policies during implementation; and, under what conditions does implementation lead to policy entrenchment versus retrenchment?

First, this study compares four cases of renewables policy implementation in US states, which vary in the scale of the policy and the amount of opposition. California and Texas acted early, deploying significant amounts of renewable energy capacity, with their policies ratcheting up over time. In contrast, Arizona and Ohio have smaller policies that have been buffeted by concerted attacks. Taken together, these cases allow for an examination of the mechanisms through which implementation leads to policy expansion or retrenchment over time. Using process-tracing, it examines how implementation decisions shaped later rounds of policymaking, including bills and proposals that sought to expand or retrench a policy.

As policy feedback theories emphasize, actors are changed through the implementation process. The paper finds that states whose renewable energy policies have created new actors, including companies, and bolstered existing advocates through new resources, expand their policies over time. In states where policies are not at sufficient scale or do not remain stable long enough to create an industry, advocates remain poorly financed and less effective, with lower social capital between groups competing for scarce resources.

Second, the research looks at public opinion data, to examine whether support for policy influences state legislators. This part of the paper describes changes in renewable energy policies across all states over the past decade. It uses a multi-level regression with poststratification (MRP) model to estimate the evolution of public opinion on renewable energy policy at both the state and legislative-district levels. With these estimates, it investigates whether state representatives are acting in line with public opinion in their district when voting on bills to repeal or expand policies, or if other factors, including ideology or partisan affiliation, are driving legislators’ votes. This paper sheds insight on how renewable energy policies change over time and which political factors pose significant barriers to decarbonizing the electricity system.