Hybrid Gas/Air-Water Heat Pump or Gas with Power-to-Heat

Could you explain that?

Gas + heat pump means that you install TWO heating systems. It is a substantial investment. And in the end, it doesn't matter whether you buy gas or electricity in winter. Financially, it's the same.

I thought until now that it would be more economical than just an air-water heat pump, where we have to buy a lot of electricity in winter, or just gas, where we wouldn't be able to use our own electricity for heating at all. So my logic was: before excess electricity is just fed in, it could support the heating during the transitional periods or at least provide hot water in summer.

In summer, the photovoltaic system produces hot water. But via the detour of the heat pump. In autumn and spring, it supports the heating. Provides part of the electricity for the heat pump. In winter, you buy electricity as usual.

In winter, the photovoltaic system would never be sufficient and would cause significantly higher costs than a gas heating system.

The photovoltaic system does not produce costs but generates income. And gas consumption compared to electricity consumption is (more or less) identical. So why install two heating systems in one house? Decide on one option and add the photovoltaic system to it. Optimize your self-consumption and enjoy a good investment.

An existing house where the heating system is being replaced? If yes, please provide some data about the house such as previous consumption etc.

Exactly as writes, maybe you can save a few euros on consumption, but you will not save the higher investment even in 100-200 years. Either gas or air-water heat pump, depending on investment costs it's not much different. I am a fan of air-water heat pump + photovoltaics, I have no electricity/heating costs and the investment averages about 1000€/year over 20 years.

Correction to the above, I actually wanted to say: "In winter, however, the photovoltaic system would never be sufficient and the air-to-water heat pump would cause significantly higher costs than a gas heating system."

Here are a few data points about the house:
- large living area (approx. 270 sqm)
- year of construction 66; insulation only rather mediocre
- windows are now being replaced halfway (the other half is from 2008; only double-glazed, but in very good condition; we will postpone the replacement by a few years)
- only radiators, no underfloor heating
- the last gas bill covered approx. 42,000 kWh; so approx. 156 kWh/m2. According to various internet portals, that would be slightly below average. However, I suspect that our hot water consumption will be higher than that of the previous owners.

Regarding the investment: If we receive a BAFA subsidy of 30% for the hybrid heating system, the price difference between the gas condensing unit and the hybrid gas-air-to-water heat pump would be significantly lower.

Regarding motivation: The option of a pure air-to-water heat pump would obviously be my favorite for environmental reasons. But I am worried that this heating system would not suit our house, insofar as it would be uneconomical due to the high electricity demand in winter. So I have been thinking about how we can integrate a renewable energy share and at the same time keep the "safe" gas option for the harsh winter months.

I have a question : Gas consumption and electricity consumption are more or less identical? What does that mean (kWh / costs?)? Sorry, I have only gotten into construction issues a few weeks ago and need to catch up...

Thanks for all your answers. I’m also looking forward to further critical feedback. Better to learn now than after the heating system installation ;-)

For an energetically poor house like yours, only gas! You should have said that earlier ;-)

The option of a pure air-to-water heat pump would of course be my favorite for environmental reasons.

Only for new builds or appropriate renovations. And then only with green electricity.

I have a question @nordanney: Gas consumption to electricity consumption is more or less identical? What is meant by that (kWh / costs?)

In terms of costs.

Heat pumps are for low-energy houses (new builds/renovations) with underfloor heating. To be effective, they require low flow temperatures. With your house, it would definitely lead to a financial disaster.

I am definitely seeing gas in these data at .