It's pretty interesting. Like many energy markets, the key challenges are actually legislation and policy related. The new government just removed a ban on new on-shore wind turbines. Which given that they are so cheap now is a sensible thing to do. The ban was madness to begin with of course. Offshore wind is of course also huge. And the UK has a lot of former offshore oil industry that is now adapting to doing offshore wind (a lot of overlap in tools and skills).
And while they are shutting down coal, they still have a huge former coal plant that is now burning biomass in London. That's a single plant that powers most of London.
Basically the way that works is that the Canadians and the British both subsidize this "green" and not so renewable power. The Canadians basically chop down what little proper ancient forests they still have on the west coast, which from an ecological point of view is criminally insane. The wood then gets shipped half way across the planet to the UK where it is burned. Shipping it of course involves burning a large amounts of nasty bunker fuel. There's nothing cheap, sustainable, clean, renewable, or green about this business. It's only economical because of the subsidies. And those subsidies exist because of fossil fuel industry lobbying and very willing politicians. That would be the same jerks that banned on shore wind in the UK.
Another key policy challenge in the UK is that energy prices are the same throughout the UK. Most of the cheap wind power is up north. Much of the demand is in the south. So they are firing up gas plants in the south at the same time they actually have a surplus in Scotland. And then prices in Scotland are high because the gas they use in the south is expensive. Even when they have more wind power than they can use and they rarely have a need for any gas power in Scotland. They are a net energy exporter most days of the year. And they are connected to the Norwegian grid which enables them to import hydro power from there.
Part of the solution is cables but installing those is expensive and challenging because it involves a lot of haggling with local councils and planning commissions. But the real solution is actually changing how this market works. This kind of change is much more challenging. Why move the power south when you can move the demand north? Variable pricing would cause that to happen.