Quality standards are required to describe both combustion equipment and wood fuels. Minimum standards for factors such as moisture content, ash content and calorific value are vital to ensure trouble free operation and so that users can buy with confidence.
The standards being adopted by most wood fuel suppliers in the UK are set out in the following quality rating – CEN/TS 14961:2005
There is a wide range of wood fuel and other forms of solid biofuel (collectively termed ‘biomass’) suitable for energy use; however most types of combustion equipment works effectively with very few types and forms of fuel.
Even with a specific form of fuel, such as wood chips, there can be major differences in characteristics and properties between different batches chipped using different chippers, from different material, with different moisture content.
CEN/TC 335 is the technical committee of the European Parliament developing the draft standard to describe all forms of biomass fuels within Europe, including wood chips, wood pellets and briquettes, logs, sawdust and straw bales.
The fuel specifications and classes for all biomass fuels are set out in CEN/TS 14961:2005, which defines certain parameters and property classes including:
- Particle size
- Moisture content
- Ash content
- Net energy content
- Bulk density in kg/m3 loose
- Chlorine content
- Nitrogen content
Many other properties may also be specified, including concentrations of many other elements and volatile matter and ash melting behaviour. Different specifications are required for different fuels, and for pellets and briquettes these include mechanical durability and particle density.
The SHWF is seeking to set up a Quality Assurance scheme to ensure that the wood fuel produced in the Surrey Hills is of a high and consistent quality.
As part of this there is a need to establish a local testing lab to assess the quality of various wood fuels against the CEN 14961 Standard and the appropriateness of various wood materials as a fuel. Currently there are only two UKAS accredited labs in the UK – one in Scotland and one in Burton on Trent.
The SHWF is working with various partners to establish local testing facilities which would enable a Quality marque to be awarded to local wood fuel suppliers whose fuel meets the required standards. Such a marque will give confidence to the end user and do much to encourage the growth of the local wood fuel industry.
As the scheme is developed, further details will be published on this website but if, either as user of wood fuel or a producer, you have any questions please contact us.
Surrey Hills Enterprises 01483 661150