If, after a thorough consultation, a heat pump is not the right choice, there are other heating systems that operate with little or no fossil fuels. However, their sustainability must be verified; for example, the source of pellets must be checked.

Pellet boiler in the basement, heat for the whole house

When it comes to biomass heating (e.g., wood), efficient and sustainable use is essential. Wood sequesters CO₂ and must come from sustainably managed forests. Ideally, only wood residues or waste should be used, such as pellets or wood chips derived from wood not intended for high-value products (forest wood, wood that is too thin, etc.).

Key takeaways:

  • Pellet heating is sustainable only if the raw materials are locally sourced and sustainable.
  • The carbon footprint is only neutral on paper, because the stored CO₂ is released during combustion.
  • The price of pellets varies and depends on the supply chain.

Solar panels on the roof – hot water for the shower

Solar thermal collectors convert sunlight into heat for water. The water can be heated for showering or washing dishes. When there is little sunlight, a storage tank retains the heat. The heating system can often remain turned off during the summer.

They are particularly recommended as a supplement to a pellet boiler to prevent inefficient operation at partial load during the summer.

Hybrid heating

In buildings with poor insulation or that have recently installed fossil-fuel heating systems, hybrid heat pumps can be used. In such cases, the heat pump is supplemented by a fossil-fuel boiler on very cold days. Once the building’s insulation has been upgraded, this boiler can be turned off.