by Victoria Harvey, Carbon Removal Research Associate at BeZero Carbon
As the IPCC reiterated this week, carbon removal is now “unavoidable” if we want to meet climate targets. At present two technologies dominate this conversation: Bioenergy with Carbon Capture & Storage (BECCS) and Direct Air Capture (DAC). As their journey to gigatonne scale begins, policymakers and investors desperately need to understand the obstacles ahead.
We urgently need more DAC and BECCS. The Intergovernmental Panel on Climate Change (IPCC), has stated that we need up to 780 and 310 billion tonnes of removal for BECCS and DAC, respectively, by 2100 to meet the 1.5 degree climate target. To date, less than two million tonnes have been removed.
But these two technologies have not been without controversy. BECCS is consistently faced with questions over sustainable biomass sourcing. Most recently with reports highlighting large-scale deforestation in British Columbia for low-carbon British energy. DAC, on the other hand, has faced pushback from campaigners who worry about moral hazard and see it as a “dangerous distraction” from emissions reductions.
Despite these important concerns, we cannot delay when it comes to removing carbon. The 1.5 degree target will not be kept alive without large-scale carbon removal, including BECCS and DAC among others, so it is vital to confront and navigate around these challenges.
This begs the question: what is their real potential and what could stop them scaling? In a first-of-its-kind Scalability Assessment for Carbon Removal from the carbon ratings agency BeZero Carbon, these intricacies begin to be unravelled. It reveals the nuance within carbon removal: what can be a barrier for one technology can be an opportunity for another.
For example, the energy component of DAC is a potential block to scaling, whereas for BECCS it is a potential accelerator. DAC is energy intensive, creating an emerging demand for an already competitive renewable energy supply, with additional indirect impacts due to this sourcing. At a project level, advancements are being made to reduce this barrier and improve efficiency. But overall, energy and its implications are a very significant barrier to scaling DAC. Meanwhile, the primary purpose of BECCS is a low-carbon energy supply, with its carbon removal contribution as a secondary function. The ability to sell this energy instead makes this a catalyst for scaling.
The inverse is true when looking at factors such as land and localised impacts, where BECCS has the largest barriers and DAC has some of the lowest. As BECCS scales, competition for land could become a prominent barrier due to its need for biomass, and preferably waste biomass such as dead wood from forests. As already mentioned, this constraint can also affect local communities and environments, in turn impacting the public perception of the method. In contrast, DAC requires a very small area of land to set up a system and the co-impacts are less present.
Despite these differences, they do face common challenges. When evaluating their ancillary value chains – the transportation and storage of the carbon – both methods face notable barriers owing to the underdeveloped nature of carbon storage. At present there are six times more DAC technology providers than storage providers. This value chain imbalance needs to be addressed and stabilised for scaling of both technologies.
Many more intricacies and comparisons can be unpicked from this assessment, across a number of carbon removal methods. But, why does this matter? And what does this mean?
As the world clambers to scale this new market and keep 1.5 and net zero alive, governments and markets need to understand these barriers and start to break them down. For example, there are opportunities to support the collection of waste feedstocks and discourage the movement of waste biomass to landfill. There are also potential commercial opportunities in nurturing non energy-intensive project developers and building carbon transportation and storage infrastructure for both mineralisation and injection.
Despite their central stage in the removal conversation, BECCS and DAC are challenged with unique barriers. As we enter the next chapter of the carbon removal journey, it is crucial that policymakers and investors become more realistic about the barriers ahead. If we break these down and address them through more targeted market and policy support we will better realise gigatonne scale.