Fire officers placed a 200m safety cordon around the plant as flames and a huge pall of smoke rose above the factory.

The blaze was confined to the biomass plant and took three hours to put out before the cooling-down process began with regular checks throughout yesterday. No-one was hurt.

Sixty firefighters were called to the site. A full-scale investigation into the cause of the blaze has been launched. Fire officials are investigating early indications that thermal oil ignited and ruptured a pipe.