Fuel Quality

The fuels listed on the Biomass Suppliers List (BSL) have been authorised because they meet the sustainability and legality requirements of the Renewable Heat Incentive (RHI) scheme. The fuels listed on the Biomass Suppliers List (BSL) have been authorised because they meet the sustainability, legality and fuel quality requirements of the Renewable Heat Incentive (RHI) scheme.

The BSL is not a quality certification scheme but currently recognises ENplus and Woodsure schemes.

  • Please be aware that the Government has introduced a suspension of fuel quality for pellets only and came into force 23rd November 2022 for a period of up to 1 year.   This means that the fuel quality requirements for wood pellets for use in biomass boilers and plant where the owner receives Renewable Heat Incentive payments via OFGEM are not required while this suspension is in effect.  Fuel quality remains an important consideration for purchasers of pellet fuels for biomass boilers and plant, as it can affect the operation and efficiency of your boiler and incorrect quality could lead to RHI payments being suspended, store clear outs, higher emissions or boiler breakdowns. Things to check: We recommend that you check the following before you order any pellets and ensure you talk to your supplier to confirm if the pellets you are ordering are right for your boiler:
    • Your boiler warrantee which may be invalidated if the correct fuel specification is not used 
    • Your maintenance contract, if any 
    • Your boiler emissions certificate – which will mention the fuel specification for the boiler 
  • For more information please read BSL guidance on Documents and Guidance page

Fuel Quality and the BSL

Early in 2021 legislation was introduced that made a number of changes to the Renewable Heat Incentive. The changes to the RHI which impact upon accredited Biomass Suppliers List (BSL) fuel suppliers came into effect on the 1st April 2022. The legislation places requirements on both self-suppliers AND commercial suppliers (Producers, Traders and Producer-Traders).

Revisions to the Regulations

The Domestic Renewable Heat Incentive Scheme and Renewable Heat Incentive Scheme (Amendment) Regulations 2021 were laid before Parliament on the 25th January 2021. The legislative changes for BSL authorised fuel suppliers are identified in Schedule 4A.

Schedule 4A of the legislation

In order to meet fuel quality standard EN 15234-1: 2011, ISO 9001: 2015 or EN ISO 17225-4: 2014or an equivalent standard, suppliers must be certified by the Woodsure Certification Scheme or an equivalent certification scheme meeting the standard in paragraph 2 or 3. For pellets, they must meet the ENplus A1 standard or an equivalent standard. 

Getting Certified – Commercial Suppliers

Details on how to join ENplus® and Woodsure are detailed below along with the application processes. For Woodsure the application process will require sampling of woodfuel.

Suppliers who are already certified by ENplus® or Woodsure are not required to take any action, but must ensure they remain certified. Note, the Ready to Burn certification is not an equivalent scheme as it is limited in focus to moisture content and legality.

Evidence of meeting the requirements via an equivalent standard or certification scheme should be submitted to bslhelpdesk@woodsure.co.uk. The BSL Administrators are not responsible for assessing suitability of equivalent standards or schemes. 


ENplus® operates as a third-party certification scheme for wood pellets. The UK Pellet Council is the National Licenser for the  ENplus® scheme in the UK and all applications from UK based pellet producers and traders must be made through them.

Please contact UKPC General Secretary & Standards Manager, Dr Matthew Goodwin at mgoodwin@pelletcouncil.org.uk for an application pack or if you have any queries regarding the certification process. HETAS is the UK Certification Body for ENplus®.

The application pack contains the following:

  • A description of the application process as it applies to both pellet producers and traders
  • A copy of the handbook which details the various requirements that must be satisfied
  • Application form and trader declaration
  • Spreadsheet to record details of trader storage facilities and delivery vehicles
  • Information on the derogations that pellet traders may apply for with reference to the handbook requirements for “on board weighing” and “active air extraction”
  • Charging structure


Woodsure is the UK’s only woodfuel quality assurance scheme, providing certification services for firewood, woodchip, briquettes, hog and pellets. 

Fuel manual templates are available on the Woodsure website and will form part of your application process. Please select and download the templates relevant to your business.

Wood briquettes


Additionally guidance is available on sampling as part of the certification process:

Sampling from a store

You can download the Woodsure Application Pack on the Woodsure website. Prior to applying please feel free to call the Woodsure team on 01684 278188 to discuss your requirements. Alternatively you can email Woodsure on info@woodsure.co.uk.

Getting Certified – Self Suppliers

Woodsure has published it’s bespoke route for self suppliers to produce a quality manual and application process early in 2022. Domestic self-suppliers may be subject to random fuel sample analysis, non-domestic self-suppliers will require an annual fuel sample test.

Get in touch

To find out more about the requirements you can contact the BSL Helpdesk on helpdesk@bsladmin.org

Supporting Notes

Guidance on what type of supplier you are can be found on the BSL website:


Self Suppliers

A Self-Supplier is a supplier who uses their own wood to fuel their own biomass boiler. Self-Suppliers are not able to sell their fuel to anyone else. They use their Biomass Suppliers List (BSL) authorisation to claim their Renewable Heat Incentive (RHI) payments.

Click here for a detailed definition of self suppliers.

Commercial Suppliers

There are three types of commercial supplier on the Biomass Suppliers List (BSL): Producer, Trader and Producer-Trader. All three are allowed to sell their fuel to a third party, however they do not have to.