biomass

Biofuels are wood and oil derived from plants.  They have the potential to supply carbon dioxide neutral heating energy.  They deliver their heat through boilers which can either be a great option where heat pumps or solar are not viable or provide a supplementary heat to a heat pump heating system.

In the UK market, biofuels are predominantly in the form of wood - often in pellet form - which offers a clean CO2 neutral heat method since the wood being burnt is simply releasing CO2 that it trapped during its growth.  Wood used in biomass is often the waste product from other processes and would otherwise have been wasted.

The key factors that need to be considered include

Source and supply of pellets:  subject to market demand and transport costs.  You should also consider whether they are from a sustainable source (Is the original source of timber being replaced?).

Pellet storage:  Pellets can take up large volumes of space so storage can be problematic.  Mostly pellets are delivered by the tonne.

Quality of supply:  Consistency of quality is essential if boilers are to burn properly.  Pellets can not be allowed to become damp.