The eco guide to heating your home

The heat is on when it comes to staying in a warm flat or house. But renewable coal and woodstoves are worth investigating

Cranking up the thermostat will cost you - and the planet: heating a room by an extra degree for a year equals 310-360kg of extra carbon dioxide released into the atmosphere.

Of course fossil fuels belong in the ground. Some will argue that not all coals are as bad as each other, emitting different levels of carbon dioxide per million BTU (British thermal unit), and it is likely that you live in a smokeless fuel zone. Ecoal50 Smokeless Coal uses 50% renewable material. (Peat briquettes - from peat bogs, which are the UK's Amazon basin in terms of carbon storage - are out of bounds.)