Peat

Peat is the first stage of coal formation. It is not strictly a coal or it can be termed as the most immatured coal. Freshly mined peat contains 90 % moisture and 10 % of solid. It cannot be utilised unless air dried to reduce moisture content to 30 % or less. Its heating value (around 20 MJ/kg) is slightly greater than wood.

As peat contains very high level of moisture and ash, it creates problems in the gasification process. Small downdraft gasifiers fueled with dry peat-pallets have been successfully tested in gas-engine system.