Reheat consultant, Martha Carrdus, provides her insights into the sustainability and quality requirements for woodfuel used in Renewable Heat Incentive (RHI) biomass systems.

The Renewable Heat Incentive (RHI) was designed to incentivise the installation of low-carbon heating and places a strong emphasis on using sustainably sourced and high-quality woodfuel, metering accuracy and requirements, and annual maintenance (explored in Reheat's 8 Step RHI Compliance Checklist). Failing to comply with these requirements can result in suspended payments, enforcement action, or even exclusion from the scheme. This article provides an overview of compliance requirements for sourcing, producing and purchasing woodfuel.

Woodfuel refers to logs, pellets, briquettes, woodchips, and hog fuel derived from woody biomass. To comply with RHI regulations, all fuel must meet criteria for both sustainability and quality. RHI participants are required to submit monthly or quarterly evidence, depending on system capacity and technology, demonstrating the sustainability credentials of the fuel used, often by submitting a valid BSL number.

Biomass system operators typically fall into one of the following categories:

• Purchasing and burning Biomass Suppliers List (BSL)-certified woodfuel from third parties
• Producing and supplying BSL-certified woodfuel (for self-use or third-party distribution)
• A combination of producing and purchasing BSL-certified woodfuel

Fuel Sustainability: Biomass Suppliers List (BSL)

Launched in 2014 by the Department for Business, Energy and Industrial Strategy (BEIS), the BSL verifies that woodfuel used in RHI-accredited systems is sustainably sourced and legally harvested. You must use BSL-registered fuel or be registered as a BSL self-supplier for sustainability compliance.

BSL certification takes into account:

• The origin, legality, and traceability of raw materials
• The distance fuel has travelled

Participants must maintain accurate fuel records and retain all documentation to ensure compliance with the regulations. Records should include fuel type, moisture content, and purchase details, including the unique BSL number (e.g., BSLXXXXXXX-XXXX) on all receipts and delivery notes.

There are different roles (e.g.producer, producer-trader, self-supplier) associated with the Woodsure and BSL schemes with different capabilities, costs and restrictions associated with each of them. Individuals and organisations should ensure that they apply for appropriate certification for their circumstances. Participants can register as self-suppliers using the BSL framework if they produce their own fuel. Alternatively, they may opt for self-reporting through the Fuel Measurement and Sampling Questionnaire (FMSQ) if more appropriate for their setup.

Fuel Quality: Woodsure Certification

From 1 April 2022, all woodfuel used in RHI-accredited biomass systems must meet quality standards. The Woodsure scheme certifies that suitable and consistent quality management systems are in place. This includes:

• Correct moisture content and support for clean air standards
• Proper processing (drying, chipping, and splitting) of raw materials
• Fuel specification and product declaration

In some instances, RHI recipients may choose to self-report on their fuel quality by completing a Fuel Measurement and Sampling Questionnaire (FMSQ) but BSL certification is still required.

A note on Waste Wood

High quality waste wood can be a cost effective and low carbon fuel source for biomass systems providing certain regulatory conditions are met. The fuel needs to be properly classified (e.g. as BSL-approved Grade A waste) and meet fuel quality standards (via Woodsure or FMSQ) to ensure compliance with Ofgem, Environment Agency and DEFRA standards. Permits from the Environment Agency may be required to burn waste wood (even clean types) depending on the location, capacity and usage of the biomass system(s).

Consultancy Support from Reheat

Navigating RHI compliance and the Woodsure and BSL schemes can be complex. Reheat offers expert RHI consultancy services to help clients understand and meet both Ofgem and BSL regulations. Whether you are sourcing fuel, producing it, or both, Reheat can guide you through certification, documentation, and reporting and compliance processes.

Simply contact our team: rhi@reheat.uk.com

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