Unlike other forms of renewable energy, biomass systems require a fuel and this represents a lifetime cost: 

• Wood pellets - £2.35 per large 20kg bag or around £90 per tonne – equating to 1.91 p/kWh
• Wood chips - £30 per tonne (at 25% moisture) – equating to 0.8p/kWh.

This compares to 1.5p/kWh for natural gas and 1.64-2.56 p/kWh for heating oil. However, it is important to note that fuel costs are dependant on the distance they need to be transported; the nearer the supplier the cheaper the fuel.