Wood is a cheap option to buy but has a very low calorific value which means it burns away quickly. This means it's incapable of maintaining sufficient high water temperatures to sustain a comfortable heating environment. It also has a high tar and residue content which can easily transfer to your chimney causing potential flue way blockages, regular sweeps of the chimney are required, more than the minimum of once a year.
It is very important to burn well seasoned or kiln dried wood and store it correctly. There are two types of wood, hardwood which has a higher calorific value or softwood which is lower, therefore hardwood gives you slightly more heat over a longer period of time, compared to the softwood.
Coal is slightly more expensive to buy than wood but it does have a higher calorific value, giving you a longer period of burning time along with an increase in heat.
The downsides are that coal has a higher ash content meaning the appliance will need cleaning more regularly than when burning wood.
Smokeless fuels that are manufactured or natural have the highest calorific value out of all the solid fuels. It gives you the longest burn period and highest heat output making this type of fuel the most suitable for solid fuel heating systems.
A natural smokeless fuel would be Anthracite and a manufactured smokeless fuel would be Taybrite, for example.
The photos above show the importance of burning the correct fuel and having your chimney swept on a regular basis. Using un-seasoned wood and being left with out a sweep for two years, it has created a complete blockage of the terminal and the flue liner has lost some of its internal diameter.
Please always use a HETAS registered Installer and have your chimney swept by a qualified Chimney Sweep.