ᐅ Gas, solar, ventilation, or heat pump?

Hello,

I am considering which heating system to use for a new build of about 115m2 (1,237 sq ft).
I would like a ventilation system with heat recovery.
How much does such a system usually cost?
Or, my general contractor suggests ventilation combined with an exhaust air heat pump. However, I am uncertain about using a heat pump at all. I think geothermal energy is fine but too expensive. How does an exhaust air heat pump work with domestic hot water?
The roof is oriented east-west; does solar make sense in this case?

Thanks in advance for any advice.

Hello,

perlenmann schrieb:
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I’m considering which heating system to use. New build about 115m2 (1237 sq ft)

There are countless options. Only an external expert consultation can provide comprehensive advice here.

perlenmann schrieb:
..
I would like ventilation with heat recovery.
What does such a system cost roughly?

Around 6,000 to 10,000 euros, depending on configuration and design!

perlenmann schrieb:
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Or what my general contractor suggests, ventilation with an exhaust air heat pump. But I’m doubting whether a heat pump is even suitable. I think geothermal is okay but much too expensive. How is it with an exhaust air heat pump combined with domestic hot water?

You would need to calculate the energy balances for that!

perlenmann schrieb:
..
Roof orientation is east-west; does solar make sense at all then?

In terms of primary energy balance, definitely yes, as every kWh saved helps the environment. The economic viability of a solar thermal system in a single-family home is often marginal.

Best regards

I don't consider an exhaust air heat pump to be effective. Either install a complete ventilation system with heat recovery or leave it out entirely.
A solar system is only conditionally recommended; it depends on the other heat sources. I am currently installing a ground source heat pump, which is very efficient with an annual performance factor of 4.8, so in my view, a solar system is not worthwhile. I would rather choose photovoltaic panels, which can reduce the electricity costs for my heat pump if necessary.

Heat Pump Seasonal Performance Factor 4.8

luemmelchris schrieb:
I don’t think an exhaust air heat pump is effective. Either go for a complete ventilation system including heat recovery, or skip it altogether.
A solar thermal system is only recommended in certain cases, depending on the other heat sources. I am currently installing a ground source heat pump with a seasonal performance factor of 4.8, which is very efficient in my opinion, so a solar thermal system is not worth it. I would rather install photovoltaics, which can reduce the electricity costs for my heat pump if needed.

Hello, good day,

A seasonal performance factor of 4.8 for heat pumps and the earth is flat! 🙄

These values only appear in the glossy brochures of manufacturers! Reliable figures are around 3.7, and only under ideal conditions that occur in about 15% of cases in practice. The investment in a ground source heat pump in Germany, whether deep drilling or surface collectors, "pays off" after about 27 to 31 years.

For my planned single-family home, my first preference is therefore a gas condensing boiler.

Best regards

F.W.

Hello,

freedy911 schrieb:
....For my planned single-family house, the first preference is a gas condensing boiler.

Considering only heating operation and domestic hot water preparation, gas condensing boilers are often a favorite. Unfortunately, room temperatures and cooling loads increase during the summer heat period because summer thermal insulation is often seriously neglected (an increasing trend). Cooling degree days (CDD) also rise. If cooling becomes necessary as a result, heat pumps have the advantage since gas condensing boilers do not offer an option for cooling.

Best regards