Bioenergy with carbon capture and storage – better known by the acronym “BECCS” – has come to be seen as one of the most viable and cost-effective negative emissions technologies.
Even though they have yet to be demonstrated at a commercial scale, negative emissions technologies – typically BECCS – are now included by climate scientists in the majority of modelled “pathways” showing how the world can avoid the internationally agreed limit of staying “well below” 2C of global warming since the pre-industrial era.
Put simply, without deploying BECCS at a global scale from mid-century onwards, most modellers think we will likely breach this limit by the end of this century.
But where did the idea for this “saviour” technology come from? Who came up with it? Who then developed and promoted the concept?
Continuing our week-long series of articles on negative emissions, Carbon Brief has looked back over the past two decades and pieced together the seminal moments – the conferences, the conversations, the papers – which saw BECCS develop into one of the key assumed options for avoiding dangerous climate change.
The interactive timeline above shows these moments in sequential order. But Carbon Brief has also spoken to the scientists who were instrumental to the concept first taking hold…
Beginnings of BECCS
In April 2001, a PhD student from Sweden travelled to the University of Cambridge to present his latest unpublished work to the 12th Global Warming International Conference and Expo. Kenneth Möllersten, who was studying at the Royal Institute of Technology in Stockholm, had spent much of the past 12 months thinking about how the Swedish paper industry might be able to financially benefit from the Kyoto carbon emissions trading system through capturing its factory emissions and sequestering them underground.
Sitting in the audience at Möllersten’s talk was a scientist called Michael Obersteiner based at Austria’s International Institute for Applied Systems Analysis (IIASA). Obersteiner approached Möllersten afterwards.
“He was quite excited and wanted to collaborate, so we decided that we should try to do something together,” says Möllersten, who now works as a senior scientific advisor for the Swedish Energy Agency.
A few weeks later, the two men picked up the conversation over the phone, explains Obersteiner:
Paper in Science
The short, yet influential paper that Möllersten and Obersteiner ended up writing, along with a diverse group of other scientists, was published in the high-profile journal Science the following September. Titled, “Managing climate risk“, it was the first time that the concept and potential of BECCS – even though it wasn’t named as such – was raised in a peer-reviewed paper. (“Initially, we were calling the concept BCRD – Biomass-energy with Carbon Removal and Disposal,” remembers Möllersten.)
The paper makes some eye-catching claims:
But Obersteiner says the paper has, subsequently, been misinterpreted by some: “I think I am the inventor of the term BECCS as a tool to allow for ambitious climate targets. But the BECCS concept was unfortunately misused for regular [emissions pathway] scenarios and not in a risk management sense.”
He adds: “The argument of the 2001 paper was to use BECCS as a backstop technology in case we got bad news from the climate system (e.g. signs of abrupt climate change, unpleasant carbon cycle feedback). Thus, the strategy should be to plan climate mitigation for a still ambitious climate target without BECCS, but still prepare for it in terms of large scale afforestation and regeneration to be prepared for the backstop, if needed. All of the integrated assessment models (IAMs) are deterministic [ie, have a single outcome per model] and do not allow for risk management thinking.”
Sweden’s paper mills
Möllersten says the first spark for the idea of BECCS came to him in 2000 when he was preparing to give a presentation at the 5th biannual Greenhouse Gas Control Technologies (GHGT) conference in Cairns, Australia. Working the idea through with Jinyue Yan, his PhD supervisor, Möllersten claims today that he “cannot remember the exact moment when we thought about this”, but he can recall the background:
Next came the calculations, says Möllersten:
Möllersten had a specific application in mind for his theoretical idea, but it was Obersteiner, he says, who took this germ and developed it into a climate mitigation risk strategy for their Science paper:
Keith and Rhodes
But at broadly the same time that Möllersten, Obersteiner and their colleagues were developing the fledgling idea of BECCS over in Europe, two scientists based at Carnegie Mellon University – a private research university in Pittsburgh, Pennsylvania – were also thinking along similar lines.
In 2000, David Keith was an assistant professor at the university’s department of engineering and public policy. Along with a PhD student called James Rhodes, he, too, had begun to flesh out some early thinking about the potential of achieving negative emissions through the combination of bioenergy and CCS.
“I had been thinking about CCS and biofuels for quite a while,” says Keith (who also presented a paper at the GHGT-5 conference in Cairns in 2000). “I’d say the idea was in the air. I started to give some talks about the combination of biomass and CCS in the late 90s. At that point, as I recall, we were thinking about biomass that implied negative emissions. What I don’t remember is when I first started to draw a cost line for biomass on plots of electricity cost vs carbon price – the biomass line starts high and slopes down.”
Keith has trawled through his archives for Carbon Brief, but says he can only find a single Powerpoint presentation from 2000 which mentions biomass with CCC: “I remember that we were talking about it in the Carnegie Mellon’s Center for Integrated Study of the Human Dimensions of Global Change in 1999 or 2000, but don’t have any slides in a readable format. I have an email to Jamie Rhodes sent on 7 November 2000. That’s the first mention of biomass and capture in an email with him.”
Rhodes, who is now a private consultant and inventor based in California, says this chimes with his memory, too:
Rhodes says he can’t recall when the term “BECCS” first came to be used:
‘Crude engineering analysis’
In April 2001 – the same month Möllersten was giving his talk in Cambridge – Keith expressed his thinking to date in an editorial commentary for the journal Climatic Change. He argued that an “integrated analysis is needed to account for the strong linkages between the use of sinks and the use of biomass energy, linkages that are inadequately addressed in most estimates of the cost of CO2 mitigation”. The article went on to undertake a “crude engineering analysis” of using “biomass to produce electricity in a power plant that captures the CO2 and sequesters it in geological formations”. He concluded:
But Keith also used the article to raise concerns about the large scale use of bioenergy for climate mitigation: “It is my expectation that measured use of biomass that focuses on arresting or reversing some of the environmental damage wrought by recent exploitation – for example, by halting and reversing global deforestation and by improving denuded soils – will provide environmental and social benefits, but that large scale use of cropped biomass for energy will not.”
Even at this early stage, scientists were seeing problems associated with deploying BECCS at scale, as well as the positives.
Over the following years, as the timeline above shows, BECCS’ prominence grew in the academic literature and conference schedules – not least through the efforts of these pioneering scientists. For example, Keith admits that he “spent a fair amount of time pushing to get BECCS into the Intergovernmental Panel on Climate Change (IPCC) special report on CCS “with some success”, which was published in September, 2005.
Integrated assessment models
But a key tipping point in the story of BECCS came when climate scientists started to increasingly include it in their modelling for sub-2C emissions pathway scenarios, often to the point that they grew reliant on it.
“Model teams picked up BECCS around 2005,” says Detlef van Vuuren, a senior researcher at the PBL Netherlands Environmental Assessment Agency and who has been a key figure behind many of the low-carbon emissions scenarios used by the IPCC. He says:
In little more than a decade, BECCS had gone from being a highly theoretical proposal for Sweden’s paper mills to earn carbon credits to being a key negative emissions technology underpinning the modelling, promoted by the IPCC, showing how the world could avoid dangerous climate change this century.
As a result, Van Vuuren now believes that climate scientists and policymakers stand at a crucial crossroads:
“I believe by far the most important question now is how to make decisions in the period up to 2020 on mitigation strategies for the next centuries in the light of the fact that most scenarios in the literature rely on negative emissions in the second half of the century to meet stringent targets. Should decision-makers follow the results of these models, and take the risk that these technologies will potentially not emerge and thus locking us in in higher concentration levels? Or should decision makers implement even stronger short-term emission reductions – even the “with-BECCS” scenarios are ambitious – and thus keeping options open? It would be good if science could help decision-makers with that crucial question.”
Timeline made by Carbon Brief using Timeline.js.
Expert analysis directly to your inbox.