News / How biomass is helping us along the way to a zero-carbon future

How biomass is helping us along the way to a zero-carbon future

6th March 2020

Renewable energy sources have proliferated in the last decade, helping the UK to transition to a cleaner, greener energy future. However, this has also caused some instability on the energy grid, as sources such as wind and solar power are intermittent.

The energy network requires finely tuned balance to function, and biomass is one answer that brings security back to the grid: helping to stabilise the system and create room for even more renewable energy sources on the system. In the UK alone, biomass accounts for around 31% of renewable energy generation.

Read on to learn more about biomass, the underrated renewable energy source which is helping to power homes and businesses across the UK.

Biomass: the basics

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 low carbon, flexible biomass 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.

How biomass is helping us along the way to a zero-carbon future - Gif Image

Understanding where biomass comes from

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

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 (such as saw-timber for construction and furniture).

Drax makes decision based on scientific evidence 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. – Drax reports on the carbon emissions from its biomass supply chain, including forestry, manufacturing and transportation, 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 we can be sure that biomass is 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 through a range of measures. These include only using responsibly sourced sawmill residues; forest residues from regions with high rates of decay or where this material is extracted to the roadsides as part of standard harvesting practices; or thinnings that improve the growth, quality, or biodiversity values of forests.

Where using roundwood, Drax sources only the low-grade by-products which cannot be used for saw-timber products, with the aim of helping to maintain or improve the growing stock, growth rate and productivity of forests; helping to improve the health or quality of forests (by using damaged wood); and is unusable by the saw-timber industry.

Drax has also committed to not using biomass where doing so would adversely affect the long-term potential of forests to store and sequester carbon, or when doing so would displace solid wood product markets or push beyond the sustainable capacity of the forest. Drax also does not biomass that comes from tree stumps.

There is scientific consensus, including the UN’s climate change body, the IPCC, 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 biomass is helping us along the way to a zero-carbon future - Biomass Image

How biomass energy generation works

Biomass is functionally similar to other thermal fuels such as coal and gas - its use creates steam, which is used to drive massive turbines, generating electricity - 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 flexible, 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.

Drax’s commitment to sustainable biomass sourcing

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 learn more about biomass?

To find out more about sustainable biomass, you can read about Drax’s commitment to giving up coal before the government’s 2025 deadline, and its responsible sourcing policy. You can also see ForestScope, a visualisation of the steps Drax takes to ensure its biomass supply chain is better for our forests, our planet and our future.

Download a biomass sustainability factsheet here

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