Which heating system? Air source heat pump or gas

Hello everyone,

we are planning the construction of a city villa with approximately 160m^2 living space with Poroton T8 in 36.5cm thickness. The house also has a full basement which is to be heated.

A gas connection would be possible in the new development area. I am currently undecided about the choice of heating between a gas heating system and an air heat pump. At a later stage, this should be coupled with a photovoltaic system.

Geothermal or groundwater heat pumps are not an option for me due to the costs.

What type of heating would you choose and for what reasons? I tend to prefer the gas heating system because I assume it will still be available in 10-15 years. Unfortunately, I find it really difficult to make a decision or an appointment at the consumer advice center did not really help me.

If you live in a mild region, take the air-to-water heat pump. In the Allgäu, maybe not so much..

Advantages of air-to-water heat pump:
- maintenance-free
- no chimney sweep fees
- no chimney
- no gas connection
- no mixer / solar thermal
- no uncertain future (CO2 tax and co)

Prejudices:
- short lifespan: no one can guarantee you anything. But: properly designed and adjusted, without short cycling and low flow temperatures, you have a good chance of a long lifespan.

Costs:
For me, the air-to-water heat pump was cheaper according to the TCO calculation. Invest the saved money in better insulation, your air pump will thank you

We live near Frankfurt am Main. What always makes me skeptical are the numerous articles about inefficient air heat pumps and that the annual performance factors are very low. What use is this to me if I have excessively high electricity costs.

The inefficiency mostly comes from the fact that the design of the entire system was not calculated but estimated! Room-by-room heating load calculations and low flow temperatures are the key to good efficiency of the system. Unfortunately, many heating installers still live in the past. Gas and oil simply forgive one or the other mistake in the design.

To put the risk of a bad interpretation into perspective:

Assumption of actual heat demand approx. 10,000 kWh.

The difference between an annual performance factor of 3 (poor) and 3.5 (okay) amounts to about €10 per month (0.25€/kWh).

In Frankfurt with a modulating air-water heat pump, an annual performance factor >4 should easily be achievable.