ᐅ Gas Heating + Solar vs. Pellet Heating

Hello everyone,

We are renovating and extending our house. Currently, we are using electric heating but plan to switch as part of the renovation. Since there is no natural gas available on our street, my idea was to switch to a liquefied petroleum gas (LPG) heating system. We will be heating two residential units with the system (90 sqm (970 sq ft) + 130 sqm (1,400 sq ft)).

Our architect has suggested pellets as an alternative, so I need some additional input to help decide on the following questions:

Liquefied petroleum gas (LPG):
- What are the initial costs of an LPG heating system?
- How expensive is a solar thermal system for domestic hot water as a “green offset”?
- Is solar thermal eligible for subsidies, and if so, what level of support is available?
- Would you recommend buying or renting the gas tank?
- What does an inspection by a certified expert and maintenance cost if I buy the tank and have to arrange maintenance myself?

Pellets:
- How reliable are the feed systems that transport pellets from the silo to the burner?
- What is the noise level like when the pellet system is refilled?
- What subsidies are available (e.g., BAFA funding)?
- Is it possible to place the pellet silo in the basement, and what requirements must the silo meet regarding moisture protection?
- What about fine dust emissions?

Thanks in advance for your opinions.

Hi,
I have a liquefied petroleum gas (LPG) tank. I decided against purchasing it because of the rental fees. The tank rental costs 179€ per year. This includes all maintenance and inspection fees. If I had bought the tank, it would have cost me around 2000€. After 10 years, an inspection would be required, which currently costs about 300€ (as of today, who knows what it will be in 10 years).

So, there isn’t much difference. One downside of the rental tank is that you are tied to the supplier for your gas supply. However, the gas price has so far been in line with the market, so I don’t feel like I’m being indirectly overcharged through the gas price.

El_Burrito schrieb:
- What are the purchase costs of a liquid gas heating system?
- How expensive is a solar thermal system for domestic hot water as a "greenwashing" measure?
- Is it possible to get subsidies for solar thermal and if so, how much?

The costs are similar to those of any other gas heating system:
€6,000 - €8,000 for the system, hot water storage tank, flue, and connections
€3,000 - €10,000 for radiators or underfloor heating and piping, depending on size and requirements
€2,000 - €6,000 for drinking and hot water pipes to bathrooms and fixtures

For renovations, the Renewable Energy Heat Act (EE-WärmeG) usually does not apply (except for some local regulations and, I believe, in Baden-Württemberg), so you don’t need solar thermal as a greenwashing measure. If you need it for KfW subsidies towards an energy-efficient house, expect around €7,000 for 10m² (108ft²) for hot water and heating. The roof should ideally face south, and the collectors should be mounted at a 45°-70° angle or the roof should be sufficiently steep.

There are subsidies from BAFA for hot water support through solar: €500 + €500 if a new boiler is installed, or €2,000 + €500 for hot water plus heating.

Additionally, there are KfW single measure subsidies (10% grant) and sometimes regional programs through state banks or local grants.

Whether it’s worth it depends on your situation. In many cases, it’s a break-even game.

Pellet systems are also subsidized by BAFA and KfW. I don’t know the subsidy rates; these can be found on the BAFA website. Subsidies can be combined as long as other subsidies for the same measure do not exceed the BAFA funding.

What about a heat pump? Are you planning to renew the screed? Then you could install underfloor heating at the same time and use a heat pump efficiently, saving yourself the hassle of refilling pellets or gas.

Hello
First of all, thank you for the feedback. We want to keep the existing screed, which is why the heat pump was excluded from consideration.

Regards