The purchase of wood fuel needn't be a complicated process, but there are important factors to consider to make sure you are getting it right. Our experts offer their insights into procuring high quality, sustainable wood fuel.
We also have a free Guide to Wood Fuel Purchasing available to download at the end of this article!
Purchasing high quality wood fuel is important for efficient and effective energy conversion. Poor quality fuel can mean poor combustion, increased emissions or unwanted by products such as tar and clinker. These can damage equipment and require expensive repairs.
Fuel quality can be defined as the physical properties of the material such as moisture, ash and energy content as well as particle size or size distribution.
Each biomass boiler commissioned will be done so with a particular fuel requirement, such as wood chip or wood pellet and an appropriate moisture content range because fuel handling and feeding requirements will slightly alter depending on the choice.
To ensure you are purchasing the best quality fuel for your own application it is highly recommended that you purchase fuel from a certified supplier, where an independent body has guaranteed that fuel is produced to a defined standard. These include the Woodsure certification scheme and the ENplus scheme. The Biomass Suppliers List (BSL) is another important reference available to identify fuels that are sustainability sourced.
Unlike fossil fuels which can be bulk purchased, wood fuels have a much larger range in energy content, which is generally between 2.9 and 4.4 MWh/tonne. This range is related to the fuel quality, specifically moisture content. High moisture content means lower energy per tonne. This means that when purchasing woodfuel, moisture content of the feedstock should be at the forefront of your thinking.
Wood fuel should always be bought based upon its energy content (£/kWh). Purchasing by weight (£/tonne) can lead to discrepancies depending on bulk density and moisture content. When purchasing by weight, moisture content of the material as received should be supplied on the delivery receipt, with a predetermined agreement in place between the parties about how moisture content is calculated. Purchasing of delivered heat is another way to ensure efficiency and losses are the problem of the supplier and not the customer.
We have recently seen a renewed focus globally on lowering carbon emissions and sustainability of fuel supply, with a move away from chipping virgin timber for bioenergy currently taking place. This move comes from the EU RED III directive, which priorities locking away carbon into long term storage such as construction (Revised Renewable Energy Directive EU/2023/2413). The alternative solution that we recommend is using residues or by products from arboriculture or other forestry activities as your primary fuel source. Significant volumes of these resources are available throughout the UK, where Reheat estimate that up to 213 million tonnes of residues equivalent to approximately 1,203 TWh of energy will be available from forest residues alone up to the year 2050. This could produce almost two years worth of the entire UK’s heat requirements (760 TWh).
With using waste or residue resources as your primary energy source, it is critical that you take quality into consideration, and that you actively manage the fuel delivered to your site to ensure no issues arise. At Reheat, we have experience in supply chain arrangement, fuel quality optimisation, system service and maintenance and ongoing client support in all facets of energy from biomass.
Contact us to discuss your wood fuel purchasing requirements, fuel quality assurance questions or identifying sustainable resources for you and discover how Reheat can support you.
