The vast majority of UK consumers have a pretty simple plan where they're not demand responsive. If it's pitch black and dead calm one Winter's night they pay the exact same price as midday in the summer if it's blazing sunshine and simultaneously blowing a gale across the whole country. Their retailler has done some estimates and figured on average they can sell power for, say, 25p per kWh all day, every day. Some days they're raking it in 'cos they paid a lot less than that, other days they wish the day would end, but if their team did the sums right it comes out profitable at year end.

There are people, especially people with EVs and who can do that sort of "turn on a dime" lifestyle where you do laundry when it's cheaper not because it's Thursday who pay 0p per kWh some hours and 45p per kWh for that bleak winter's night.

For now that second group are a minority but they do exist.

The enabling technology is a bit more sophisticated than your French red lamp. "Smart" meters relay your usage constantly so you can be charged in 30 minute chunks, the same way the wholesale electricity market works. This also means you can see at a glance what's going on. So that's nice. The usual conspiracy people insist this is a future tool of control by government, just like almost everything that has ever been invented, bar codes on groceries, mobile phones, newspapers, parking tickets, everything.