Follow the money
Darren, you are right, of course. But it's worse than you state.
The politicians have two entirely different constituencies. First, the naive greenies who want to "save the planet" and think they have The Answer. More stealthy are the subsidy suckers, companies who produce the economically unjustifiable Windmills and Solar PV panels. They supply money to the pols as contributions, complimented by the votes from the greenies.
It's a marriage made in hell. Lots of votes AND plenty of campaign funds to advertise how GREEN they are. Even the odd, temporary job in their district pouring concrete for windmill tower footings. The fact that it's all going to be paid for by the poor electricity rate payer and taxpayer is irrelevant. It's not costing the Pols anything! They get re-elected and get to continue their scam. Personally, I think burying the cost in increased electricity rates rather than in more obvious direct taxes is brilliant. In a disgusting sort of way.
And yes, if the money were applied to energy research on low waste fission reactors (thorium) and other undeveloped technologies, we might eventually have a true solution. We sure do need one for that time to come when all the natural gas is consumed in space heaters and gas turbine generators. England will need LOTS more gas turbines for the rather obvious times when the wind stops blowing and the sky is overcast. But that never happens, does it?