Wood sawdust briquettes. (Source: © juliedeshaies / stock.adobe.com)

Fuel produced by compressing wood waste, e.g. sawdust, into a compact form. Wood briquettes are usually made from waste from the wood industry, like sawdust, bark, chips, etc. After drying, they are finely crushed and compressed under high pressure and elevated temperature, usually without the addition of any binding agents. They are then used as fuel in ecological boilers.