Britain’s biomass generation carries big emissions risk, report claims

A study released today (17 October) by US-based environmental organisation the Natural Resources Defense Council (NRDC) examines the ‘full system costs’ of wind and solar energy relative to biomass for replacing coal and meeting the UK’s clean energy targets for the period 2020-25.

Considering the latest technology costs; the cost of ensuring reliability of supply, and carbon costs, the NRDC concludes that wind and solar power are likely to be less expensive than burning trees for biomass, and that many forms of biomass – such as that from forests – have been producing higher carbon emissions than coal and natural gas for decades.

Burning wood for electricity emits around 40% more carbon pollution than burning coal to produce an equivalent amount of energy, the NRDC reports, as the carbon that trees have accumulated over long periods of time is released into the atmosphere when burnt. Moreover, the use of trees for biomass disrupts vital carbon sinks and impedes ongoing forest carbon sequestration.

“The science already shows that burning biomass on a mass scale for electricity increases carbon pollution and is extremely harmful to the environment,” said Sasha Stashwick, a senior advocate with NRDC. “The emissions risks associated with biomass are simply too big to be ignored, and now we see that the economics of biomass don’t make sense as the UK strives to replace coal and decarbonise its power sector.

“This report clearly indicates that when accounting for total economic costs, cleaner alternatives like wind and solar are the lower-cost solution for a coal-free UK – it’s just good economic sense.”

‘Misunderstanding’

However, the report has been discredited by the Renewable Energy Association (REA), which in 2013 founded the Wood Heat Association to support the modern wood heat & biomass generation.

The REA’s head of policy and external affairs James Court told edie: “It is a shame that yet again, misleading reports are fundamentally distorting the facts with a misunderstanding of how the biomass industry works. The REA and wider industry are always eager to engage with any report into the carbon savings that biomass can achieve, something this organisation did not try to obtain.

“The wood used in biomass power production is typically from low-value wood such as harvest residues, thinnings, tree tops, limbs, and sawmill residues, as well as misshapen and diseased trees not suitable for other use. This is sourced from actively managed timber producing forests in the UK, EU, and US. 

“It is also worth noting that forest cover in both the US and UK is higher now than at any point over past 60 years as a result of better forest management from across the wood product industry. The evidence shows that demand for wood products keeps forest-land forested. This call to leave this low value wood unused and rotting while we continue to burn fossil fuels does not stack up.

“Carbon savings delivered by UK biomass power generators are independently audited, including a full life-cycle analysis. The rules in the UK insist on significant savings relative to fossil fuels and Drax are achieving carbon savings of over 80%. The picture is even clearer for the UK’s wood heating industry, which shows an average of 87.47% greenhouse gas emissions savings compared to the EU fossil heat average, with heat being one of the most difficult areas to decarbonise.

“As with any industry, if biomass is done badly there will be poor results, but the UK has the one of the highest standards for sustainability and accountability, and biomass has a key part to play in decarbonising the UK’s heat and power sectors in a reliable, cost-effective and low-carbon way.”

Biomass conversion

Biomass has played an increasingly significant role in Britain’s energy mix, with generation levels more than tripling from 6.6 TWh in 2009 to around 22.4 TWh in 2015, or 9% of total national generation. The Government hopes that an increase in biomass boilers in homes and businesses will help to meet an EU target of getting at least 15% of the nation’s energy from renewable sources by 2020.

Increases in biomass power are predominantly due to conversions of existing coal plants. Drax Power is now responsible for 38% of total generation from biomass in the UK, having converted three of its coal plants to burn biomass since 2013.

This is not the first time biomass power generation in the UK has been heavily scrutinised. Last year. A Government study found that biomass boilers in the non-domestic sector were around 10-20% less efficient than expected.

Luke Nicholls