Prices aren't determined by costs and never have been. Prices are only determined by supply and demand. Not saying it's right, but you're framing this as some kind of unexpected phenomenon when this is obviously how things work.
More regulation is needed to stop people dying in the cold (obviously) but let's not forget why price signals are useful: the possibility for naked profiteering should act as a huge incentive for renewable generators to invest! But in reality, the UK government is going to start cracking down on wind and solar, which is insane. Residents of areas with planned renewable projects also have a habit of blocking them for inane reasons.
If owning a wind farm is a license to print money, we should LET PEOPLE BUILD THEM!