Geothermal heat pump and hot water heat pump???

Hello dear community,

At the moment, I am concerned with the question of domestic hot water heating. Photovoltaics and ground source heat pumps are already quite certain. Now the question arises how to heat the domestic hot water most efficiently. With the ground source heat pump or with an additional hot water heat pump? How efficiently does a ground source heat pump heat the domestic hot water in summer? The geothermal heat is cooler than the ambient temperature. Hot water heat pumps have the positive side effect in summer of cooling the air; moreover, they are apparently available in combination with ventilation. Then the ground source heat pump could be completely switched off in summer, which could possibly increase its lifespan. But of course, you would be introducing additional technology that can break down. I am rather a friend of as little as necessary. Are there any recommendable combination devices in this context that heat, ventilate, and produce hot water??? Three wishes at once...

I would be very grateful for suggestions and experiences.

Best regards Judyyy

We have a heat pump with which we heat the building and produce hot water. There are four of us in the household and we have a 300 l buffer tank. Even in the warmest summer, we have had no problems so far.

Now the question arises for me, how to most efficiently heat the domestic hot water

With the existing or already planned heat generators. Adding another derivative alongside a geothermal heat pump is nonsense, even if it might be a bit more efficient (which I doubt). Then the cost goes from 15€/month for hot water to 12€. Plus the installation effort, purchase price, and space consumption.

Forget active cooling via fans, unless it is a proper air conditioning system with corresponding cooling capacity. The effect is marginal, but the installation effort is comparatively high. If you are planning a geothermal heat pump anyway, look into passive cooling. Although it is also only a small but noticeable effect, it uses significantly less electricity and simultaneously regenerates the ground probes, which in turn benefits their efficiency in winter. Passive cooling is usually an add-on module for the heat pump and is priced between 1000-2000€.

Hello everyone, the same technology is planned for us, we are building Kfw 40+. Heat pump with geothermal baskets for heating (underfloor heating) and hot water (300-liter boiler, 4 people), but a second device is not cost-effective. Controlled residential ventilation is separate, photovoltaics and storage due to 40+ funding for 2 units.

We needed 329 kWh of electricity for the heat pump during the 6 summer months (without heating). At an electricity price of 23.35 cents, this amounts to a total of 76.82 euros or 12.80 euros per month. We use a 200-liter storage tank.

Since we have a photovoltaic system, the water is heated almost for free during daylight hours (plus taxes + investment costs).

Additional technology cannot be so cheap that it would even remotely pay off. Such a geothermal heat pump has a COP beyond 4... what should an additional system achieve? Then you might as well use DHW, but that doesn't make sense either.

Hello,

thank you very much for your numerous replies.



What does ST mean???

Regards
Judyyy