The problem is the UK sees maybe 1-2GW of renewable generation sometimes in winter while demand is about 50GW. So you'd have to overbuild 25x to cope with these

The problem is the UK sees maybe 1-2GW of renewable generation sometimes in winter while demand is about 50GW. So you'd have to overbuild 25x to cope with these days. Keep in mind the UK already has about 30GW of solar and wind potential nameplate capacity. Your suggestion would result in a requirement of 700GW of solar and wind to be installed. On windy and sunny days would result in probably 350GW of generation, at least 300GW more than we need.