4. Variability of fuels and equipment

The reference biomass for fuel applications is wood: it accounts for the vast majority of biomass fuels and has been used for many years in appliances designed primarily for this fuel. The fairly recent development of pellet appliances has led to a diversification of biomass sources, creating new problems. So, among the main difficulties linked to the characteristics of biomass in domestic heating appliances today, the main ones are:

• fuel humidity ;

• cleanliness;

• diversification of sources (corrosion and pollution problems in particular).

Matching the heating appliance to the fuel used is therefore a key factor in the system's smooth operation. Finally, installation is an important feature that can enable a heater to operate under widely...