Biomass: The renewable energy source supporting the zero-carbon transition

What is biomass?

Biomass is organic matter, such as wood or plant materials, which is used for power generation, in industry and as an alternative source of heating. Biomass is used in the same way as coal, but with much lower associated carbon emissions.

As the largest provider of renewable electricity in the UK, Drax Power Station in Yorkshire uses biomass as a low carbon flexible technology to meet electricity demand alongside other sources. These can be weather-dependent or ‘intermittent’ renewable sources, such as wind and solar, and other more established technologies such as nuclear, hydro and gas.

Where does it come from?

Biomass can be produced from different feedstocks (or materials), including agricultural or forestry residues, dedicated energy crops or waste products such as uneaten food.

The type of biomass used by Drax is high-density, compressed wood pellets.

These pellets are sourced from responsibly managed working forests in the US, Canada, Europe and Brazil, and are largely made up of low grade wood produced as a by-product of the production and processing of higher value solid wood products (e.g. saw-timber for construction and furniture).

Drax makes science-based decisions to inform the type of wood it sources. Its sourcing is designed to maximise the positive carbon contribution sustainable biomass can deliver and helps to protect and improve the forest ecosystem.

These wood pellets are shipped to the UK and used at Drax’s power station in North Yorkshire – and any carbon emissions from its biomass supply chain, including forestry, manufacturing and transportation, are reported to the energy regulator, Ofgem. Overall, generating power with biomass at Drax is over 80% lower carbon than coal and over 60% lower carbon than gas.

How do we know it’s sustainable?

Biomass producers and users must meet a range of stringent measures for their biomass to be certified as a sustainable and responsibly sourced. Thanks to these robust measures, monitoring and reporting, biomass is a cleaner and more sustainable option than fossil fuels.

In order to ensure its biomass reduces emissions in the most effective way possible, it commits to maximising carbon benefits by: Using:

• Responsibly sourced sawmill residues.
• Forest residues from regions with high rates of decay, or where this material is extracted to roadside as part of standard harvesting practice.
• Thinnings that improve the growth, quality or biodiversity value of forests.

Only using roundwood that:

• Helps to maintain or improve the growing stock, growth rate and productivity of forests.
• Helps to improve the health and quality of forests, for example by using storm, pest or fire damaged wood.
• Is not merchantable for use as saw-timber products.

And not using:

• Biomass that drives harvesting decisions that would adversely affect the long-term potential of forests to store and sequester carbon.
• Biomass that increases harvesting above the sustainable capacity of forests.
• Biomass that displaces solid wood product markets.
• Biomass that comes from stumps.

Scientists – such as the United Nations’ climate change body, the IPCC – agree that the carbon emitted by biomass power generation is cancelled out by the increased rate of carbon uptake in the working forests where trees continue to flourish.

This means biomass power generation is carbon neutral and once wood pellet supply chain emissions are counted, biomass is classified as low carbon.

What’s more, with Drax’s pioneering BECCS project, the power station is aiming to go beyond carbon neutral and become carbon negative, storing more carbon dioxide than it releases over its lifecycle.

How is biomass used to generate renewable electricity?

Biomass is used to make renewable energy in the form of steam used to drive massive turbines, which in turn generate enough electricity to power entire cities. This works similarly to how other thermal fuels such as coal and gas generate power, but crucially with significantly lower carbon emissions.

Over the last 10 years or so, renewable energy sources that depend on weather conditions such as wind and solar power have proliferated, helping to green up the grid and reduce the carbon intensity of the UK’s energy network.

However, this increase has also introduced new challenges for power system stability. The grid needs to be kept finely tuned. As biomass is a power source that can be “turned up” or “turned down” when needed, it helps to provide balance to the grid and helps to meet energy demand at those times when the sun isn’t shining, or the wind isn’t blowing.

The biomass used at Drax accounts for around 12% of the UK’s total renewable energy electricity mix. Analysis by researchers working at Imperial College London recently found that during the decade 2010-2019, biomass generated more power than solar panels and provided an outsize contribution to reducing emissions and wholesale power prices.

Who do we work with to ensure we’re sourcing your electricity sustainably?

Drax works with a several partners to ensure that its biomass is responsibly sourced and is part of the Sustainable Biomass Program. Our parent company has also established an Independent Advisory Board, composed of leading scientists and sustainability specialists to help ensure that its biomass production continues to contribute to the environment in a positive way.

Where can I go to find out more?

If you’re interested in finding out more about Drax and biomass, check out Drax’s commitment to giving up coal ahead of the government’s 2025 deadline, its responsible sourcing policy and ForestScope – a data visualisation tool highlighting the steps Drax takes to ensure its wood pellet supply chain is better for our forests, our planet and our future.