ᐅ Geothermal heating combined with solar energy?

Hello fellow home builders,

we are currently finalizing our plans.

We were recommended a geothermal heat pump (drilling).
Now we are considering supporting it with a solar system (hot water storage tank).

Does that make sense?

What additional costs can we expect for a solar system with approximately 400L (105 gallons) storage?

Is this even feasible?

Best regards

Hello,

blackst4r schrieb:
...We were recommended a geothermal heat pump (drilling)....

Then have the entire system properly calculated and sized! Quite a few rather unusual "setups" are sold in this field.

blackst4r schrieb:
..now we are considering supporting this with a solar system (hot water storage) – does that make sense?

For the seller, yes! 😉 There has already been a lot written about this. Just try using the search function.

blackst4r schrieb:
..Is this even possible?

Technically, almost anything is possible. What is actually more sensible and effective is optimizing the entire system with a heat generator! Many heating system installers even have difficulties with that.

Best regards

Hello,

blackst4r schrieb:
We were recommended a geothermal heat pump (drilling)

Is such a system even realistically feasible for you? You listed NRW as your location; in many parts of NRW, groundwater is being extracted, so a geothermal heat pump doesn’t really make sense there.

blackst4r schrieb:
Now we are considering supporting it with a solar system (hot water storage). Does that make sense? What additional costs should we expect for a solar system with about a 400L (105-gallon) storage tank?

If this "consideration" is based on what your seller told you, €uro is right. If it is simply an unrefined idea from your side, then take a look around this forum.

“More” is rarely better. If the geothermal heat pump makes sense for your property, the calculation is correct, and the costs are manageable for you, you won’t need another energy source; the geothermal heat pump covers all functions.

Why do you want a 400L (105-gallon) storage tank anyway? Do you have that many children who would empty the tank quickly? 🙂

Kind regards

Thanks first of all to you 🙂

The borehole is planned to be 80 meters deep (about 260 feet), so it will not connect to the groundwater but serve as a geothermal probe.

The idea came from me, not from the seller.

Our builder has equipped 15 houses with geothermal heating this year.

The building area should be well suited for this.

I was told that a 400-liter (about 105-gallon) tank is sufficient for 4 people, while 300 liters (about 80 gallons) is too small... but it’s good if the geothermal heating is ultimately enough.

If the geothermal system doesn’t reach the required temperature in winter or more heat is needed, an electric heating element will switch on, which consumes a lot of electricity... that’s why the idea of adding a solar panel system came up.

Hello,

blackst4r schrieb:
If the geothermal heat doesn’t reach the required temperature in winter or more heat is needed, a heating element switches on, which consumes a lot of electricity.. that’s why the idea of a solar system came up.

A properly designed brine system can operate without a heating element! This is usually only needed during building drying. Therefore, it makes sense to have it available only "on loan" during the first year of operation.
Equipping multiple houses with a brine system is no problem. But which seasonal performance factors are actually achieved in practice? This is where the real difference becomes clear.
Instead of a solar thermal system, I would rather improve insulation or install photovoltaic panels on the roof. This way, you can avoid the seasonal performance killer that is the "combi storage tank." Possibly, a higher efficiency rating can also be achieved.

Best regards

Photovoltaics would exceed the budget after all.

Tomorrow I will know more about the system and the house insulation.

I will get back to you.

Thank you for the explanation.