Both parties want renewable energy.
They want it for different reasons.

Most Americans like renewable energy. That much has been clear for years. What this study asked is why. The research was conducted at the Yale Program on Climate Change Communication, where XandY's co-founders Abel Gustafson and Matt Goldberg were then based, together with colleagues at Yale and George Mason University. The team surveyed a nationally representative sample of 966 registered voters (Ipsos KnowledgePanel, late 2018) and had them rate 16 possible reasons for moving the country to 100% clean, renewable energy, then pick the single most important one. They then built statistical models to find which beliefs best predict support for renewable energy policy, separately for Republicans and Democrats.

The stated reasons tell one story. For 15 of the 16 reasons, more than half of all voters said the reason was "very" or "extremely" important. But the partisan gaps were large. The widest was "reduce global warming": 86% of Democrats called it very or extremely important, compared with 40% of Republicans. It was the single most important reason for a third of Democrats, and by average rating it was the least important reason for Republicans. Republicans' top reasons were practical: getting energy from sources that never run out, and reducing energy costs. The one reason where Republicans rated higher than Democrats was "protect God's creation."

The predictive models tell a matching story. Among Republicans, the strongest predictors of policy support were the belief that renewables improve the economy and create jobs, and how much effort they think the U.S. should put into reducing global warming once the costs are considered. Among Democrats, worry about global warming and interest in climate solutions did more of the work. A relative weight analysis, which sorts out how much each predictor contributes when they overlap, found that economic beliefs explained about 14% of the variation in Republicans' support but under 5% for Democrats. Interest in climate solutions did the reverse.

The takeaway is not that Republicans only care about money or that Democrats only care about climate. Forty percent of Republicans still called reducing global warming very or extremely important, and 77% of Democrats said the same about reducing energy costs. It's a matter of emphasis. For communicators and policymakers, the data point in a clear direction: lead with economic benefits for Republican audiences, and frame renewables as a climate solution for Democrats. Later academic experiments by the same researchers tested exactly that, and found that a message about cost savings worked well for both.