The post I was responding to said

> I forsee the future lies in 'smart' electricity meters which can charge different rates at different times of day - perhaps with minute by minute live pricing.

That's what I was responding to, not the day/night predetermined pricing.

They could still have a price limit, paid for by charging a bit more when prices are lower, it doesn't have to be priced directly to the grid to have impact on usage.

A max price guarantee would also give the supplier an incentive to have their planning in order.