In the UK, differential tariffs were introduced in the 1970s for the benefit of homeowners with electric storage heating. On the Economy 7 tariff you get substantially discounted power for a seven hour period overnight, often as much as 50% lower than the peak rate. Pretty much every British EV owner uses this tariff and a timed charger, because it offers huge cost savings.

https://en.wikipedia.org/wiki/Economy_7