A biomass heating system is only as good as the woodfuel it’s fed, otherwise it cannot fulfil its potential. There are several certifications in the industry to indicate the quality and sustainability of wood pellets. Read below to learn the difference between ENplus®, BSL, and RHI, and what makes them important.

What does ENplus® mean?

ENplus® is a certification for wood pellets made of solid biomass. It was introduced in 2010 to guarantee the quality of the product. An impartial third-party body assesses aspects like pellet size, mechanical durability, density, ash and moisture content, calorific values, and the percentage of additives. ENplus® certification not only sets the criteria for the production of pellets but for their distribution as well. 

There are three quality classes outlined by the standard: A1, A2, and B, which differ in their calorific value, permitted ash content, its melting temperature, etc. Class A1 are premium wood pellets used in private household boilers or stoves. They have a high calorific value and produce the least amount of ash, about 0.5%-0.7%. ENplus® A1 wood pellets are made from either hardwood or softwood, homogeneous or mixed.

Class A2 is used in larger installations. They are produced from a combination of raw materials, such as whole trees without roots and other by-products and residues from wood processing that are not chemically treated. The percentage of ash they produce does not exceed 1%. They have a lower calorific value compared to A1.

Industrial pellets can be certified as “EN B”. Their ash percentage can be up to 3% and they cause higher levels of pollution.

Note: Another certification scheme exists for different types of woodfuel, called Woodsure. It applies to firewood, woodchip, briquettes, hog fuel, etc. Woodsure grants the Ready to Burn certification mark to woodfuels with a moisture content of up to 20%.

Why choose a certified pellet and how to recognise it?

If all of them serve their purpose and produce heat, does it matter what wood pellets you use? Choosing pellets of certified quality and origin has several benefits:

• - Higher efficiency - Although higher-quality pellets are generally more expensive, their higher calorific value means they produce more heat per unit compared to lower-quality ones.

• - Sustainability - Certified pellets contribute to sustainable forest management and a responsible wood processing industry.

• - Eco-friendliness - They reduce carbon emissions and contain low levels of harmful substances that have a negative effect on human health.

• - Credibility - The certification does not incur significant extra costs for ENplus® pellet producers. It encourages healthy competition and eliminates bad actors in the industry, thus protecting the reputation of wood pellet producers and of pellets as a whole.

How can you tell if pellets are certified?

The first way to recognise the ENplus® pellet certification is by looking for the ENplus® logo on the bag. It must be accompanied by the company’s ID (number and two letters indicating the country of origin). Note that only ENplus® - certified companies are allowed to use the logo and all bag designs are subject to approval by the International Management of ENplus® (EPC) or the respective National Management, where present.

A second, extra step you can take is checking the ENplus® database and looking up the name or ID number of the producer, trader, or service provider. The list provides information on each company, as well as the status of their certificate (active, suspended, or terminated).

Any misuse of the logo, counterfeiting certification documents, etc., results in the suspension of the certified company’s certificate and its inclusion in an ENplus® blacklist.

Tips for choosing the right pellets

There are several basic guidelines one can follow when deciding what pellets to buy:

1. Consider the information provided on the label - Even pellets from reputable brands may slightly differ in their characteristics. High-quality pellets must have:

• - Low ash and dust content

• - High ash melting temperature

• - Consistent wood pellet size

• - Low moisture content

• - High heat output (kW/h)

2. Check the certifications on the bag - as mentioned above, these will guarantee the traceability and transparency of the supply chain and transport and answer the question “Are wood pellets sustainable indeed?”.

3. Use a trusted supplier who can assist you with their experience and input, directing you to the best manufacturer and brand.

4. Before buying your supply for the entire winter, you can conduct a test at home to evaluate first-hand how the pellets perform in your heating system.

What is the Biomass Suppliers List (BSL)?

The Biomass Suppliers List (BSL) is a list of eligible woodfuels under the Renewable Heat Incentive (RHI) scheme. Fuel types registered on the BSL include logs, woodchip, wood pellets, and wood briquettes. To register their woodfuel, biomass suppliers must prove that it is at least 60% less carbon intensive than the average EU fossil fuel equivalent and that it complies with the UK Timber Standard for Heat and Electricity’s definition of legal and sustainable woodfuel. There are several different supplier types such as Self-Supplier, Trader, and Producer.

Unlike ENplus®, BSL is not a quality scheme and does not guarantee the quality of the fuel.

What is a BSL fuel number?

A BSL authorisation number is a unique number that pertains to a particular product. It’s printed on your invoice when you purchase BSL-certified woodfuel and must be kept in order to be presented to the government under the RHI scheme.

What is the purpose of RHI and what does it stand for?

RHI (Renewable Heat Incentive) is a government financial incentive which aims to promote the use of renewable heat. It is administered by Ofgem (the Office of Gas and Electricity Markets). There is a domestic RHI (DRHI) scheme for households, as well as a non-domestic RHI (NDRHI) scheme for businesses, public sector and non-profit organisations.

Under the DRHI, eligible households who have a renewable heating system and meet the criteria are entitled to receive quarterly payments over a period of 7 years. As of 31 March 2022, the DRHI is closed to new applicants.

Is biomass renewable or nonrenewable? 

Biomass is considered a renewable energy resource, particularly if it comes from a sustainable source. That is why biomass pellets are eligible under the UK’s RHI scheme.