Bioenergy with carbon capture ‘will not deliver negative emissions’

Environmental groups have warned that bioenergy with carbon capture and storage (BECCS) will not deliver the “negative emissions” touted by advocates, whilst also being expensive and damaging to the environment.

Organisations including Friends of the Earth, WWF and Greenpeace expressed their opposition to the technology in an open letter to the Department for Business, Energy and Industrial Strategy (BEIS) written as part of their response to a consultation on potential options for removing greenhouse gas from the atmosphere.

Drax recently revealed it was applying for planning permission to install carbon capture and storage equipment on the two of the four biomass units at its power station in Selby. The company claimed this would allow it to become the world’s first “negative emissions” power station.

“BECCS relies on the premise that because forests and other plants absorb carbon as they grow, bioenergy is carbon neutral,” the letter explained. “Proponents argue that when biomass is burned to fuel a power station, capturing and sequestering the smokestack CO2 emissions would thus make the process carbon negative.”

However, putting aside the emissions created in processing and transporting the wood pellets burnt at Drax, most of which are sourced from the US, the letter said it was wrong to consider biomass generation as being carbon neutral. In addition to the emissions produced during combustion, carbon dioxide trapped in the soil is also released during harvesting.

It said even in the best-case scenario, in which trees are replanted and regrow immediately, replacing older trees with saplings reduces the amount of carbon stored in the forest, and that carbon capture and storage can never mitigate this “foregone sequestration”, which has often been “neglected” in carbon accounting.

“Together, this means that forest biomass harvest for energy, even under BECCS, has a negative impact on the climate, with consequences that can persist for decades or more—far outside Paris Agreement timeframes,” it stated. “This holds true even under the industry’s definition of sustainable biomass sourcing of thinnings from managed forests.”

The letter said pellets produced using “damaging logging practices” such as the clear-felling of mature hardwood forests, “routinely enters the UK energy market”, warning: “This biomass is high-carbon and its sourcing contributes to forest degradation, yet it takes place under existing governmental and corporate sustainability standards.”

It said any attempts to produce the fuel domestically will have “serious implications” for land use, agriculture and biodiversity in the UK: “Reducing the land available for food production risks either greater intensification of agriculture or a reduction in agricultural output. If biomass production has to rely on agricultural intensification in combination with monoculture biomass plantations, it risks damaging biodiversity if forests are converted to plantations heavily reliant on agrochemicals.

“Once the carbon costs of pesticide use, fertiliser use, harvesting and transportation are factored in, any climate mitigation that is realised may be lower than if the same land was used for another carbon-absorbing activity, such as native tree-planting,” it added.

Furthermore, the letter said biomass generation is a “hugely expensive and inefficient source of power”, with recent figures from the think tank Ember putting the subsidies to Drax in 2020 at £832 million, including £258 million in tax breaks: “Rather than prioritising additional subsidies to run BECCS at Drax, a high priority from a climate perspective would be to replace Drax and other industrial scale bioenergy with low-carbon renewables.”

It said BECCS “sacrifices genuine opportunities” to remove carbon dioxide from the atmosphere: “Protecting and restoring natural carbon sinks, including forests, peatlands, grasslands and wetlands are the most effective and proven ways of sequestering carbon and are thus critical. In addition to pulling CO2 out of the air and storing it in organic materials, these approaches can secure food supplies, improve the resilience of ecosystems and communities, and enhance biodiversity.”

Drax has previously said it is aiming to be able to generate power from biomass without subsidies by the time its current Contracts for Difference expire in 2027, but that it would be seeking subsidies to capture and store the emissions.

In a report published in 2017, Chatham House claimed that biomass is a more carbon intensive source of power than gas or even coal. The think tank did not sign the letter but expressed its support for its message. Daniel Quiggin, senior research fellow for its energy, environment and resource programme, said: “It’s an incredibly risky bet for the government to overly rely on bioenergy with carbon capture and storage.

He continued: “Government attention needs to focus primarily on low-carbon technologies that are affordable now and balance some of the risks of BECCS by separating the net-zero target into a decarbonisation target and a separate CO2 removal target.”

Jonathan Marshall, head of analysis at the Energy and Climate Intelligence Unit, commented: “These warnings come amid concerns that energy and climate models are over-egging the potential of BECCS. The heavy reliance on a technology that is facing increasing questions over its true sustainability is likely to cause concern for policy makers, especially in sectors where decisions are being delayed today on the back of expectations that negative emissions technologies will come to the rescue.

“The government is currently making big calls on the future of greenhouse gas removals, at the same time as stalling on actions that can cut carbon now. Pushing this dangerous mindset has been a long-term strategy of oil and gas companies; we should expect our policy makers not to fall into the same trap.”

A spokesperson for Drax said: “Climate change experts and scientists at the UN’s IPCC and the UK’s Climate Change Committee have stated sustainable biomass is critical to reach global climate targets – both in generating renewable electricity and in delivering negative emissions with bioenergy with carbon capture and storage.

“BECCS is the most cost-effective negative emissions technology available now. It has been proven to work at Drax – the first unit could be operational as soon as 2027, permanently removing millions of tonnes of CO₂ from the atmosphere every year.

“Drax is committed to ensuring best practice in health and safety, operational efficiency and sustainability across the group and intends to invest accordingly to deliver this outcome.”