ᐅ It takes a long time for hot water to arrive.

Yes, water usage is low, electricity consumption is five times higher

Air circulation should definitely be incorporated in new buildings. However, that opportunity has likely passed...

It’s an older building. And no, the electricity costs are extremely low. We use 600 kWh per year for hot water with the tankless water heater, and that already includes the electricity for the pressure booster pump, which runs on three-phase power!

When showering at 41°C (105.8°F), it only consumes about 5 kW. No circulation pump, no long pipes from the basement, and no heat loss from constantly keeping hot water stored in a tank.

So where could it possibly be any cheaper?

The circulation operates very precisely and is time-controlled. Additionally, it is specially insulated. This keeps heat loss very manageable.

Just without an instantaneous water heater. I have the same hot water costs in a 4-person household with daily showers for everyone and a weekly bathtub bath. With circulation and all the extras... of course, the conditions are different, but that’s how it is...

Elina schrieb:

So where else could it be cheaper?

With a heat pump, you have about four times lower electricity costs.
Now you can offset the additional installation costs; in your case, the tankless water heater might actually be cheaper, but I can’t judge that.
In general, considering average consumption as well as installation, maintenance, and repair costs, a tankless water heater is the most expensive option you can choose.