Wood pellets are a highly compressed standardised product made from sawdust, normally without other additives.
Their advantages are:
• they are a consistent fuel with low moisture content which can be easily handled in automated systems;
• bulk density is around 4 times that of wood chip, requiring less storage room making them more convenient at a domestic scale. In other countries bags of pellets are commonly sold on filling station forecourts.
Their disadvantages are:
• supplies of locally made wood pellets are hard to find in the EU, most are imported at present;
• they take energy to make and are often transported long distances, reducing the environmental benefits of using a wood fuel;
• they are expensive, around twice the price of wood chip.

For the CARBOROBOT boilers the wood pellet is essential biofuel.