Bioenergy with carbon capture and storage, or BECCS, sounds like the perfect net-zero solution: grow some form of plant material, burn that material for energy, capture the CO2 emitted during combustion and store it underground. You can then grow more plant feedstock in the same area, which sucks up carbon from the atmosphere, meaning at the end of it all, you have created energy at a net loss of carbon.
But despite its utopian pretensions, BECCS has yet again found itself at the centre of a scandal involving unsustainable practices in the sourcing of biomass feedstock. In October, the BBC’s Panorama alleged that UK-based power producer Drax bought logging licences to cut down two areas of environmentally-important forest in British Columbia – including large areas that have been identified as rare, old-growth forest.
A new report released in November by sustainability non-profit Forum for the Future outlined 30 strict conditions that must be met if BECCS is to deliver positive outcomes for society, climate and the economy. But after a series of similar controversies calling into question BECCS’s sustainable credentials, is it finally time to call it quits on the tantalising dream of this fanciful decarbonised energy technology?
Problems with sustainability and costs
First conceived in the 1990s, BECCS is the world’s only carbon removal technology that can also provide energy. BECCS plants can capture anything from the process emissions from biofuel and biohydrogen production to combustion emissions from biomass-fuelled heat and power generation, organic waste-to-energy and industrial applications fired by biomass (cement, pulp and paper) or from using biochar as a reducing agent (steel). Instead of being stored, the captured carbon can alternatively be used to create various products.
Today, only around two megatonnes (Mt) of CO2 are captured each year from biogenic sources, with around 1Mt of CO2 stored in dedicated storage. More than 90% is captured in bioethanol facilities, one of the lowest-cost BECCS applications due to the high concentration of CO2 in the process gas stream. From January 2021 to June 2022, companies announced plans for more than 50 new facilities involving BECCS, which would add around 20Mt of CO2 of capture capacity per year. Based on current projections, carbon removal through BECCS could reach around 40Mt of CO2 per year by 2030 – although that still falls well short of the 250Mt per year by 2030 required under the International Energy Agency’s (IEA) Net Zero Emissions by 2050 scenario.
Despite the IEA’s endorsement, the technology has its drawbacks. In 2019, campaign group Sandbag warned that Europe’s BECCS plans would accelerate rather than address the climate crisis by potentially destroying forests quicker than they can grow back, due to the “staggering” amount of tree cutting needed to fuel BECCS plants. The group warned that the amount of biomass pellets needed to fire Europe’s BECCS plants would equate to half the size of Germany’s Black Forest each year. Similarly, the Daily Telegraph reported earlier this year that the UK government’s BECCS targets would require burning the equivalent of the New Forest National Park every five months.
“You’ll eventually start eating into carbon stocks,” says Pieter de Pous, leader of the Fossil Fuel Transition Programme at environmental think tank E3G. “On a very fundamental level, there is an opportunity-cost issue of mobilising biomass for energy purposes because storing carbon in natural ecosystems is actually another way of taking carbon out of the atmosphere.”
Then there are the supply chain issues. In 2019, a decade-long investigation by media, independent watchdogs and NGOs revealed that global demand for wood pellets to burn for biomass energy – primarily in the UK and Europe – was devastating forests in the south-east US. The investigation exposed damaging logging practices used by Enviva – the world’s largest wood pellet manufacturer – to supply wood pellets to the bioenergy industry, including the clearcutting of iconic wetland forests. This involved chopping down vast quantities of native hardwood trees in biodiversity hotspots. Enviva would then ship the pellets from these ravaged forests to utilities overseas such as the UK’s Drax Power Station.
“Traceability is a big issue,” says Dr Alexandre Köberle, an advanced research fellow at the Grantham Institute at Imperial College London. “How can you tell where this material is coming from? It is being produced in the US, burnt in the UK by one company and then sunk into the North Sea by another – and as you scale the industry up, that will become even more of a problem.”
There are also real cost challenges that have yet to be ironed out. Carbon capture and storage (CCS) technology is still in its infancy and continues to be expensive and under-deployed, with the limited capacity coming online likely to be focused on hard-to-abate industries such as cement and steel. “We don't expect anyone ever to do CCS seriously in the power sector,” says de Pous. On the bioenergy side, there is a fundamental problem in that – unlike wind, solar and batteries – the costs will actually go up as the industry scales “because your feedstock is your main cost factor: limited supply, more demand,” says de Pous. “So, to make it work, you are going to need to sustain very generous subsidies indefinitely.”
In fact, just days after the UK government committed to increased forest protections at COP27, a new report commissioned by the US NGO Natural Resources Defense Council (NRDC) revealed that it spent almost £2bn to subsidise the logging of forests for bioenergy in 2021 – the vast majority going to Drax. This was the highest out of the 11 European countries analysed and constituted a 70% increase from 2015. In the future, subsidies for just one UK BECCS project are forecast to hit £3.8bn ($4.59bn).
BECCS: where is it working?
Yet, the UN IPCC's Sixth Assessment Report concluded there is a role for BECCS in the net-zero transition, and many companies are investing in the technology. The largest operating BECCS project to date is the Illinois Industrial CCS bioethanol plant, which has been capturing 1Mt of CO2 per year for permanent storage in a deep geological formation since 2018. The Red Trail Energy bioethanol project also recently came online in North Dakota. Other small-scale bioethanol facilities are capturing CO2 in Europe and the US, but these either sell the CO2 to greenhouses for yield boosting or use it for enhanced oil recovery.
A large-scale biomass-fired power plant in Japan was retrofitted with carbon capture in 2020, although a storage site for the CO2 has yet to be identified. That same year, Drax’s UK power plant, the largest biomass-fired plant in the world, started a pilot capturing up to 1tCO2 per day at one of its four 660MW biomass units – however, the CO2 is released after capture.
Globally, around 40 bioethanol facilities are planning to capture CO2 before 2030, totalling more than 15Mt of capture capacity, according to the IEA. There are also plans to capture around 15Mt of biogenic CO2 from heat and power plants, with around two-thirds from dedicated bio-power plants and a third from waste-to-energy plants.
In industry, five cement plants are planning to integrate biomass feedstock into the clinker production process and retrofit carbon capture, utilisation and storage (CCUS). Note, however, that some cement plants plan to use BECCS for carbon neutrality rather than removal, such as the Brevik Norcem plant in Norway, the Cementa Slite plant in Sweden and the K6 Lumbres project in France. There are also a couple of projects targeting CCUS retrofits at pulp and paper mills in Norway and Indonesia, and plans for two hydrogen production facilities to run partly or fully on biomass.
However, “I am not aware of anywhere in the world where BECCS is currently being done sustainably,” says Köberle. De Pous concurs.
To get to that point, the IEA concedes the industry needs to evolve in key areas: the capture technology needs to become more efficient and less energy-intensive, with much hope pinned on the development of solid absorption capture and biomass gasification technology. Biomass facilities should also be focused within industrial clusters to leverage economies of scale and aggregation. Finally, the BECCS value chain – the biomass supply, feedstock pre-processing, bioenergy plants and CO2 storage – are rarely co-located, which means additional mapping and infrastructure is needed to connect them in a sustainable and traceable manner.
However, de Pous believes the IEA’s faith in the technology is built on false premises. “The energy system modellers have misunderstood the issue of opportunity costs and competing land use. They talk about lots of degraded land ready to be exploited, not understanding there is a reason the land is degraded. There is no virgin land left out there that is not already performing a function.”
An arrow in the quiver
It remains an open question whether, despite all its negative press, BECCS should keep its place in countries’ net-zero armouries, or whether the time and resource would be better spent elsewhere. As well as the IEA, the UN’s IPCC and the UK’s independent advisory panel, the Climate Change Committee, have both given the technology their blessing.
The 2021 Coalition for Negative Emissions’ report, produced by various stakeholders within industry, found that at least one gigatonne (Gt) per year of negative emissions from BECCS is needed globally by 2025, and 4Gt annually by 2030, to keep global warming within the Paris Agreement’s target of 1.5°C of warming. That could be mobilised sustainably from agricultural residues, woody residues and energy crops grown on degraded land, states the report.
Similarly, a recent National Renewable Energy Laboratory report indicates that by 2035, the US will need 100Mt of carbon removals from BECCS to offset remaining positive carbon emissions in the power sector. The deployment must start by 2026 and the installed capacity range must be 7–14GW by 2035.
In the UK, a Drax-commissioned study by the energy consultancy Baringa, found that Drax’s BECCS project will save the country £26bn in reaching its 2050 net-zero target. Baringa reached that figure by calculating the opportunity cost of having to start another project afresh as well as the value of facilitating decarbonisation earlier in the country’s pathway. “BECCS is critical to energy security as well as global efforts to urgently address the climate crisis because no other technology can deliver reliable, renewable power, whatever the weather, whilst permanently removing carbon dioxide from the atmosphere,” a Drax spokesperson told Energy Monitor.
Others are less convinced, however. An analysis done by Tim Searchinger, a senior research scholar at the Princeton School of Public and International Affairs and senior fellow at the World Resources Institute, found that to produce 20% of human energy needs from bioenergy by 2050 would require an amount of biomass equal to all the plants harvested annually across the entire world: all the crops, crop residues, wood and grasses eaten by livestock. “The world does not have the room,” Searchinger writes. “Every time we dedicate land to bioenergy, we sacrifice the opportunity to use that land for some other human need, ranging from food to carbon storage. The trade-off is a bad one because bioenergy is an inefficient use of land.”
Furthermore, a 2021 NRDC analysis revealed that a large portion of lifecycle CO2 emissions deriving from bioenergy actually occur offsite – away from the biomass power station – and are therefore uncapturable by the addition of CCS at the smokestack. These emissions – equal to approximately 60% of the stack emissions at the plant – come from logging the trees, converting them into wood pellets at manufacturing facilities and transporting them across the world. The analysis indicates that employing BECCS at a power station like Drax’s, while relying on the biomass supply chains that dominate the company’s fuel supplies today, is responsible for roughly 80% as much carbon as a coal plant per megawatt-hour, even after accounting for subsequent forest regrowth and on-site carbon capture at the power plant.
“There aren't any countries in the world presently using BECCS from biomass combustion at scale," says Elly Pepper, deputy director for NRDC. "Since it hasn't been proven at scale, no country can or should rely on it. Very few countries have captured carbon from mixed waste combustion – which would be classified as partial BECCS – except on a very small, really experimental scale,” she adds.
“I think both bioenergy and CCS are plays of operators to keep coal plants running a bit longer,” says de Pous. “Neither are scalable solutions.”
As with most debates surrounding potential climate solutions today, the arguments around BECCS can quickly devolve into research paper tit-for-tats between advocates and detractors – with the veracity of the findings often difficult to discern. However, for what it is worth, one of the most reputable analyses of the issue sees merit in both camps. The 2019 analysis from Imperial’s Grantham Institute concludes that BECCS could be a useful tool in the net-zero transition but should be deployed on a relatively small scale and only in areas where it has already proven to be beneficial – primarily for biofuels rather than power production.
“It is not a silver bullet; it is one arrow in your quiver,” says Köberle, a co-author of the report. “CCS isn’t scaling fast enough to support these 10–15Gt per year sequestration scenarios, so the limited capacity you do have should be saved for bioliquids rather than bioelectricity.”
He points out that electricity has many cheap, carbon-free alternatives such as wind and solar power; whereas biofuels have few, particularly for aviation and freight transport. To that end, second generation “drop-in” biofuels can be synthesised by breaking down the molecules in biomass and reassembling them to imitate fuels used in engines.
“Maybe having 100 or so BECCS power plants globally is not a problem – to provide some baseload power – but the feedstock has got to be sustainably sourced agricultural or forestry residues," adds Köberle. “There is a value in BECCS, but how it is done is extremely important – and the Enviva/Drax example shows exactly how not to do it.”