They will become a necessity once fossil fuels become scarce, which will probably come for shale oil first. But anyway it's unlikely to ever get really bad, as production of renewable power equipment already approaches replacement rate (rate at which they will, being continuously deployed, satisfy current energy needs - all kinds of energy not just electricity - faster than they will be wearing out, which is 20-30 years). In only a few years production of solar panels and batteries will be way over replacement rate, launching an accelerated transition. Fossil fuels in the U.S. will be still abundant then.
So for now, it's just the climate change. Maybe change in attitude of Republicans is in fact completely rational and is down to that: factors that made them concerned, such as safety of energy supply/energy independence/cost, are no longer a concern, only factors they don't care about (climate change), are.
Except this is wrong. 3-4x efficiency gains on top of cheaper prices has a substantial impact even in the US.
This is why the Inflation Reduction act is called that, you can lock in energy at flat prices, while fossil fuel prices rise at higher than inflation rates, and pass that cost saving on to everything that uses energy.