Giusi wrote
> Bob F > wrote

>>> How can that be true, no hot water is wasted in a cold fill dishwasher.

>> But heating it may cost more, if the water heater is gas, for instance.

> No,

Yes, he did say MAY.

> because a tank water heater works 24/7 no matter how cheap

Plenty of the water heaters dont store the hot water.

> (and that's strictly temporary) gas may be.

Not necessarily.

> The dishwasher fills with a couple of liters of water, rinses, drains, then 3 liters that it heats.

Yes, but a dishwasher that uses piped hot water doesnt have to use hot water all the time.

> It takes less than a minute to heat because it is so little water. Same for the rinses.

The rinses arent necessarily done with hot water. Only my last one is.

> We are encouraged to use our dishwashers in Italy because it uses less water and energy than handwashing.

The energy claim is very dubious, particularly with drying.

> Potable water and energy are both a potential big problem here.

But they dont necessarily use less total energy, particularly with drying.