ᐅ Comparison of Different Heating Systems

Nutshell schrieb:

How much does it actually cost per year to heat and provide hot water with an air-to-water heat pump plus underfloor heating in a KfW55 house of about 130sqm (1400 sq ft)? I mean in euros, the real cost, not estimated.

I still have a small section without external thermal insulation composite system (ETICS). So far, it’s not a finished KfW55 house. For 120sqm (1300 sq ft), with the electricity contract starting October 1st, the monthly bill is about €40-45 (including hot water, controlled mechanical ventilation present). Indoor temperature is around 22°C (72°F). Or that would be the expected cost. Some of the electricity is supplied by photovoltaics.

KarstenausNRW schrieb:

I still have a small area without exterior thermal insulation composite system (ETICS). So far, the 55-standard house isn’t fully completed. For 120 sqm (1,292 sq ft), the electricity contract starting 01.10 results in about €40-45 per month (including hot water, with mechanical ventilation installed). Indoor temperature is around 22.x degrees Celsius (72.x°F), or that would be the cost. Part of the electricity comes from the photovoltaic system.

That’s great!
Do you know how many kWh of electricity are needed for hot water and heating (not household consumption)? From both the grid and the photovoltaic system.

I have always needed around 7,200–8,200 kWh of gas for heating and hot water in my KfW 55 house. I have 5 sqm (54 sq ft) of solar thermal panels for hot water on the roof.

Nutshell schrieb:

Do you know how many kWh of electricity is used for hot water and heating (so not household consumption)? From the grid as well as photovoltaic.

Last year, a little over 2,000 kWh.
However, the house is only half insulated with external thermal insulation composite system (ETICS), according to the heat pump's meter. So it could also be 2,150 or 2,300 kWh, depending on the accuracy of the internal meter.

Nutshell schrieb:

How much does it actually cost per year to heat and provide hot water with an air-to-water heat pump plus underfloor heating in a KfW55 house of about 130 sqm (1400 sq ft)? I mean the real cost in euros, not just an estimate.

We have a bungalow with 105 sqm (1130 sq ft) and use about 1800 kWh per year for heating and hot water. The cost depends on your contract; we still pay 20 cents per kWh.

Nutshell schrieb:

I always needed around 7,200–8,200 kWh of gas for heating and hot water in my KfW 55 house. I have 5 m² (54 ft²) of solar panels for hot water on the roof.

For estimating consumption with a heat pump, take your gas usage and divide it by 4 or 3.5. This factor is the coefficient of performance (COP). A heat pump produces 3 to 5 kWh of heat from 1 kWh of electricity.

Heating is one thing, hot water is another.
If water is kept at 70°C (158°F) around the clock, 24/7/365, you will notice this very clearly in the energy consumption.