@Edent I think a fridge is a bad example for demand shifting because the fridge uses more electricity when you are opening and closing it a lot, taking cold food out, putting warmer food in, etc. That usually happens when you're cooking in the evening - which is when electricity demand and therefore prices are at their peak.

A better example would be a tumble dryer, washing machine, or dishwasher, where you filled it in the evening and then allowed the energy company to turn it on overnight.