Heat production: Heat- only systems

Slideshow of images for Wales Energy Crops Information Centre

The use of biomass for heat production is one of the oldest technologies in the world. Today biomass-heating systems are clean, high tech and efficient. They can take a range of fuel types including logs, wood chips and pellets. Miscanthus and Short Rotation Coppice can both be utilised as chips or pellets. If you would like to grow your own crops to supply your own fuel, the calculator on the Miscanthus page can be used to give you an idea of the cropping requirement for various systems sizes. Economic comparisons between fossil fuels and biomass fuels are available on the economics page of the website

Heat-only systems can range in size from stoves, heating a single room through to boilers and burners providing heat for larger buildings such as schools, leisure centres etc. Log-fuelled boilers are available for wood, though wood-chip or pellet based systems would be used for Miscanthus and SRC. Manual loading and automatic loading systems are available, with the later being the more expensive of the two. Heating technologies can supply warm air heat, or be used to heat water for radiators or under-floor heating.

Biomass heat offers a number of opportunities:

Fuel production of wood chip or pellets for own use or for commercial sale.
Opportunities to become an Energy Services/Supply Company (ESCO)
Self sufficiency
Local community scale heating projects

Pellet or chips?

Pellets	Chips
Positive	Positive
Smaller fuel store required	Cheaper than pellets to produce and buy
Reliable fuel source	Production of chips – rural job creation
Lower moisture content	More readily available
Less boiler service and maintenance required
Production of pellets – rural job creation
Negative	Negative
Cost more	Higher moisture content
Currently not as available	Fuel quality harder to maintain
	More maintenance work
	Less flowable than pellets

The use of pellet or chips may come down to size of storage facility and the source fuel. Miscanthus can also be baled, though bales are more applicable to larger scale operations and for delivery to power stations.

Choice of boiler system will depend upon:

heat load
heat use patterns throughout the year.
original fuel source i.e. wood or Miscanthus due to different ash characteristics etc.
fuel type (pellets, logs, chips, straw)
whether a manual or automatic system required.

The cost of the boiler system will also be dependent on the above details and talking directly to the manufacturers and suppliers will give you the best estimate of costs. Case studies may give you more of an idea of the type of system you would like to install and these are often available on supplier websites such as these examples from Talbotts and Econergy . Boiler suppliers will be able to help you decide which system is most appropriate. The Wood Fuel Wales website is a valuable resource of information that will enable you to find installers and suppliers located in your area as well as giving a wealth of further information. Although dedicated to wood as a fuel the information is also applicable to Miscanthus.