UK sued for counting wood burning with carbon capture as ‘negative emissions’

Pictured: Wood biomass pellets. Image: Drax

Plaintiffs say BECCS technology relies on flawed accounting assumptions because it sees the carbon captured from wood burning as negative emissions when the process is at best neutral from a climate perspective.

“The government’s rationale for BECCS as providing negative emissions violates international carbon accounting protocols underpinning the Paris Agreement, to which the UK is a signatory,” said a statement from The Lifescape Project and the Partnership for Policy Integrity (PPI), two environmental groups that are the complainants in the case.

“Burning forest biomass and relying on BECCS for negative emissions will not contribute to the government’s legal obligation to achieve net zero by 2050,” they warned.

Carbon payback period

The UK government’s biomass strategy, published in August, contains a chapter on BECCS, which explains how the technology can deliver negative emissions.

BECCS relies on a simple assumption: Because trees and plants suck up CO2 from the atmosphere when they grow, burning biomass for electricity and capturing the related emissions to store them underground will result in negative emissions.

However, scientists say the negative emissions will only be realised once new trees are planted and grow sufficiently to absorb the same amount of carbon dioxide – a process called the ‘carbon payback period’ that can take several decades.

“Biomass energy is classed as renewable because it is assumed that the carbon in harvested materials will be removed from the atmosphere through regrowth and, over time, the carbon emitted on combustion will be reabsorbed,” said the European Academies Science Advisory Council (EASAC), an association bringing together the national scientific academies of the 27 EU member states, plus Norway and Switzerland.

But while in the case of solar and wind energy, typical carbon payback times – linked to mining and manufacturing – are just months to a few years, the payback period for biomass is highly uncertain and depends very much on the type of biomass used.

“Short-rotation crops and residues from sustainable forestry operations may have short payback periods but harvesting whole trees and additional extraction of stemwood has been shown to have payback periods of many decades or even centuries,” EASAC said in a commentary published last year.

“This delay is too long to contribute to meeting Paris Agreement targets” of reaching climate neutrality by 2050 in EU countries, it warned, urging policymakers to “suspend expectations that BECCS can deliver significant CDR removals by 2050”.

Carbon accounting ‘gimmick’

Even supporters of BECCS acknowledge some caveats. The UK’s own biomass strategy, for instance, says genuine carbon removals are only possible “if the biomass is ‘well regulated’ meaning if it is sourced, sustainably with appropriate certification” to avoid deforestation.

Campaigners, meanwhile, say BECCS can at best be counted as zero emissions but cannot possibly contribute to negative emissions in the short term.

Indeed, under UN accounting rules, harvesting wood is considered a source of carbon that adds CO2 to the atmosphere and is treated as zero in the energy sector to avoid double-counting the emissions.

Counting the emissions again when biomass is burned is therefore either a mathematical mistake or a carbon accounting trick, said Mary Booth, director at PPI, one of the complainants in the UK legal case.

“This is an accounting gimmick,” Booth told Euractiv, insisting that BECCS provides no net change in carbon emissions.

“Previously, the carbon was embodied in the trees and was thus not in the atmosphere. Now, the CO2 is held below ground, so is still not in the atmosphere. But there has been no new ‘removal’ of CO2 from the atmosphere,” Booth stressed.

“They are committing the first deadly sin of carbon inventories – they are double-counting the removal of the carbon. It’s really not an exaggeration to say that the whole scheme is based on the inability or unwillingness of policymakers to do the math!”

EU repercussions

According to campaigners, the UK legal case could reverberate beyond Britain and have repercussions across the Channel, where the European Union is promoting BECCS as a negative emissions technology.

On 30 November last year, the European Commission put forward a scheme to certify removals of carbon dioxide from the atmosphere with new EU-wide rules for third-party verification, management of certification schemes, and functioning of registries.

BECCS was listed in the proposal as one of the main technologies to ensure permanent storage of CO2, alongside carbon farming techniques like agro-forestry and carbon storage in products such as wood-based construction materials.

In addition, the EU executive announced €180 million in funding for a project to convert an existing heat and power biomass plant in Stockholm into a “world-class, full-scale” BECCS facility.

Supporters of the project say the Stockholm BECCS plant has the potential to remove around 7.0 Mt CO2eq over the first ten years of operation and pave the way for a new market of net carbon removals.

But Booth said the project is based on the flawed assumption that biomass is always zero emission, pointing to evidence showing that wood pellets used in UK biomass plants and imported from America have contributed to logging biodiverse forests in the US Southeast as well as Canada, contributing further to climate change.

“In the case of the Swedish BECCS project, assuming the wood comes from Sweden, if you did the math and added up all the sinks and all the emissions from the energy sector and the land sector… you’d see that the BECCS project yields zero emissions, at best, not negative emissions,” Booth told Euractiv.

“This comes back to the old problem – they want to treat biomass as actually having ‘zero’ emissions, based solely on the accounting convention of counting biomass as zero in the energy sector,” Booth said.

The project promoter, Stockholm Exergi, did not respond to Euractiv’s request for comment.

Frederic Simon, EurActiv.com

This article first appeared on EurActiv.com, an edie content partner