ᐅ LWW, Gas, or Geothermal Operating Cost Experiences

Hey everyone,

We are currently planning our small house and are facing the big question of which type of heating system to choose.

Gas heating + domestic hot water
Heat pump (air-to-water)
Geothermal energy

I have researched the different types extensively. It is also clear that the initial investment costs vary.

Which heating system is the most cost-effective in terms of operating expenses?

Here are a few key details:
KfW-55 standard
About 140m² (1,500 sq ft)
Controlled ventilation system
Underfloor heating on ground floor and upper floor

Thank you very much for your advice

Hello,

when it comes to ongoing operating costs, I would definitely recommend geothermal energy.

We built our house last year, also using geothermal heating, and have just completed our first winter. I record the daily electricity consumption and the heat output, and compare these in an Excel spreadsheet.

During periods when temperatures dropped as low as -14°C (7°F), our consumption was between 20 and 25 kWh per day. At 17 cents per kWh, that comes to between €3.40 and €4.25.

Now that outside temperatures are between 0°C and 10°C (32°F and 50°F), consumption has dropped to between 9 and 16 kWh per day. I don’t think you can get much cheaper heating during winter.

The annual performance factor (Seasonal Coefficient of Performance) ranges between 3.93 and 4.27.

Our key specifications:
KfW55 standard
170 m² (1,830 sq ft)
Mechanical ventilation with heat recovery
Underfloor heating on ground and upper floors

Best regards
Michael

Thank you for your figures. Does anyone else have comparison values for air-to-water heat pumps and gas?

I now have a concrete offer for our house, where basically the only decision left is which heating system to choose (and whether to go with brick cladding or not, but I can handle that myself).

Gas including solar included
Air-to-water heat pump around €3,500 (about $3,700)
Geothermal heat pump around €13,000 (about $13,700)

No problem, but I don’t quite understand your offer.

Gas including solar and also heat pump for 3500€? Why combine gas and heat pump?

Regards,
Michael

No, sorry, that means 1 item per paragraph.

So
- Gas is included in my offer
- Heat pump 3500€ (instead of gas)
- Geothermal energy 13000€ (instead of gas)

Take a look at the available funding options, as you can deduct these from the relevant costs.

Last week, we received our grant of 5,000€ (about 5,450 US dollars) for the ground-source heat pump. I believe the subsidies for air-to-water heat pumps are significantly lower.