BIOMASS ‘The biodegradable fraction of products, waste and residues from agriculture (including vegetal and animal substances) forestry and related industries, as well as the biodegradable fraction of industrial and food waste’ (EU Renewables Directive)
A more practical definition has been provided by the Alternative Energy Association (AEA):
- Biomass is the resource that is grown or collected.
- Biofuel is a fuel manufactured from biomass (chips, pellets, bio-diesel etc.)
- Bioenergy is the use of the fuel to supply energy – be it heat, transport or electricity.
Biomass is a very broad term includes trees, crops, algae and other plants, as well as agricultural and forest residues. It also includes many materials that are considered as wastes by our society including food and drink manufacturing effluents, sludges, manures, industrial (organic) by-products and the organic fraction of household waste.
Biomass can further be divided, with different terms for different end uses: heating, power (electricity) generation or transportation. We tend to use the term ‘bioenergy’ for biomass energy systems that produce heat and/or electricity and ‘biofuels’ for liquid fuels for transportation.
At present BENI’s activities are focussed on developing a market for woodchip derived from SRC willow. This is currently the most readily available and easily grown source of biomass in Northern Ireland, but it is certainly not the only one. Other sources of biomass comprise forestry and its wastes, sawmill residues and clean waste wood. In the future it may include miscanthus (elephant grass) and fast-growing hardwoods. BENI supports research into all forms of biomass which may be grown in Northern Ireland.
The biomass sources in Northern Ireland which have been identified by Renewable Energy Association UK (REA):
- Forest residues
- Wood residues from sawmills
- SRC willow
- Other perennial energy crops
- Crop residues
- Poultry litter
For biofuels and gas:
- Annual crops (e.g oil seed rape)
- Meat and bonemeal
- municipal Solid Waste
- Landfill gas
- Farmyard manures
Advantages of biomass:
- Converts well to heat
- Security of supply
- Short supply chains – it’s grown locally
- Supply can be stored
- Long term pricing contracts available
- Low greenhouse gas emissions/carbon neutral
Disadvantages of biomass:
- Variable quality and heating value
- Higher boiler costs than conventional heat, but offset by lower fuel costs providing savings over the lifetime of a system.
- Less flexible operating systems (especially at smaller scale)