In a residential household of 160 m2 with underfloor heating a biomass boiler was replaced with a new one of 16 kW because the old one did not reach the performance expected. The innovation consists of using a set of additional RES systems to be as independent as possible from the grid, and included 5 kW of photovoltaic panels, 1 kW of wind power and 4 panels for solar thermal energy, additionally to the biomass boiler. The house is occupied by 2 persons, but there are times when they are up to 6. The boiler feeds an inertia tank for domestic hot water, and the heating is divided in 2 zones, one for the underground heating and the other for conventional heating.
The household had installed a biomass pellet boiler beforehand, so the owner had his preferences clear. The old system gave him several problems and did not achieve the desired comfort. Since they wanted a biomass system, they bought a new boiler of higher quality. The installation process was quite easy since there was an old biomass boiler already, so the technicians just had to connect the new system. On the other hand, because of all the renewable systems installed in the household the electricity bill is almost null and as the resident comments, the environmental impact is really low. The system was financially helped with regional aid.
|New heating system in use
|Previous replaced heating system
|Useful energy demand (kWh/m2a) – Before and after building shell renovation
|Before: 175 kWh/m2 a
After: 100 kWh/m2aa
|Installed capacity (kWth) – Before and after
|Before: 28 kW
After: 16 kW
|Input energy – Before and after
|Before: 28,000 kWh
After: 16,000 kWh
|Initial investment (purchase and installation)
|Yearly savings on the energy bill (compared to previous system)
|Yearly energy savings (compared to previous system)
|Yearly CO2 emission reductions (only heating system replacement)
|13 t CO2
This best practice is issued from the activities of Work Package 4 “Preparation of instruments for replacement campaigns” of the REPLACE project. Read it to discover many more best practices illustrating the benefits of innovative low-carbon and renewable heating and cooling systems.
- Publication date
- 8 May 2023