Yes, but water heater tanks are by themselves inefficient as it stores heated water regardless of it being used.

If I ever get a house (millennial lol) I’d want to have a tankless water heater. That way supply meets demand exactly.

If I ever get a house (millennial lol) I’d want to have a tankless water heater. That way supply meets demand exactly.

Tankless is crazy LESS energy efficient than a tank heat pump water heater. Why? In tankless you’re having to CREATE THE HEAT. With heat pump tank you don’t. You’re citing the inefficiency of storing a tank of hot water, but the insulation on a decent (not garbage) hot water heater is really really good! The heat loss through the insulation is VERY small. You could turn off the water heater entirely and come back days or possibly weeks later and the water is still hot.

You still have to create the heat for a water tank, too …

A tankless needs to heat water extremely quickly, which needs a lot more energy. More energy than you can get out of electric heat for a whole house, so most of them are gas.

I guess you might be able to put a bunch of small electric tankless heaters at each hot water tap, but that's a lot more electrical work and points of failure.

That, and each one of those tankless heaters requires its own dedicated 15 or 20 amp circuit so if you install a shitload of them all over the house you’re going to fill up your breaker panel really quickly.