Biomass for heat and power in the UK
The bioenergy industry is heavily subsidised by public money but large-scale biomass burning damages nature and the climate.
In 2019, bioenergy was classed as the UK’s single biggest source of renewable electricity. However, burning wood biomass emits more CO2 than coal. A misleading ‘zero carbon’ rating in UK energy policy gives biomass plants access to substantial tax breaks and renewable energy subsidies. Most of our bioenergy comes from imported wood pellets and chips. This is increasing our carbon emissions and putting unacceptable pressure on forests around the world.
Dirtier than coal
Wood burned for energy emits more carbon per kilowatt hour when it is burned than coal. Bioenergy backers argue burning wood can be carbon neutral as the trees regrow. It takes decades for new trees to regrow and lock in the carbon that was released by burning. The trees would have continued to suck carbon out of the atmosphere if they remained standing.
Under international climate rules, bioenergy can be counted as zero emissions in our energy sector because carbon emissions are supposed to be counted where trees are harvested. Most of the trees burned in the UK are harvested overseas, so they are classified as zero carbon in the UK. Often, this carbon accounting is inadequate and many emissions are ignored. Millions of tonnes of bioenergy emissions are completely missing from climate accounts.
Threats to nature
Woody biomass imports burned in the UK are sourced either through logging existing forests or new plantations. Both can seriously harm ecosystems. Harmful practices such as logging in sensitive and protected forest habitats, home to threatened and rare wildlife, are widespread in the UK biomass supply chain. This is in spite of government and corporate sustainability standards. Alternatives, like new energy crops displace food crops to vital wildlife habitats.
Why protect forests?
When left in the forest, deadwood, branches, and tree stumps provide shelter for birds, such as woodpeckers and owls, and other incredible wildlife. Deadwood supports a huge range of smaller organisms from insects to fungi, as well as micro-organisms essential to the food chain. It protects soil from eroding into streams and serves as a source of nutrients and moisture for young trees.
Can bioenergy work?
Bioenergy can play a small role in the UK's low-carbon energy mix. But only within an industry based on genuine waste materials sourced domestically. Decision makers should not lock the UK into a system reliant on large scale biomass crops and imported timber. The government must prioritise genuinely low-carbon renewables such as solar and wind and phase out fossil fuels.