The only really critically necessary government intervention is making sure the grid can handle this.

It would probably help if they mandated smart electric storage heaters on new builds but beyond that I'm not sure you need to do much more.

You can rely on people's self interest to buy a new washing machine that saves them money, for instance.

I was thinking more along the lines of international standards for how the appliance could tell that it was in a period of low electricity pricing.

Also, since green tech often saves fewer actual dollars from a consumer's pocket than the "real" cost of the externalities saved, subsidies and/or eco-friendly certification would also be good.

> I was thinking more along the lines of international standards for how the appliance could tell that it was in a period of low electricity pricing.

The obvious solution to this is grid frequency. It's already a requirement for solar grid tie invertors for example.

Demand shaping generally reduces the peak demand so the grid can usually handle much more power on average than before.