Background: The Oxford Martin School convened a “Greenhouse Gas Removal Conference” over the three days spanning September, 30 to October 2, 2015. Around 100 people from academia, industry, and NGOs attended to share updates on promising carbon removal research and innovation, and to discuss strategies for the field to gain the policy support it needs to flourish. Being one of, if not the only, conference dedicated to the concept of carbon removal, the event provided a good look into the state of the carbon removal field today. Here’s are the three most important things I took away from the event:
1. Research and development of carbon removal solutions is progressing in a number of the carbon removal fields. For one, there was encouraging data presented by the community of researchers that are investigating ways to enhance the natural ability of silicate minerals to sequester carbon directly from the air. While there still were a number of presentations that relied on back-of-the-envelope calculations to suggest the potential of this technique for carbon removal, work such as that by Dutch researcher Francesc Montserrat is staring to show real laboratory-scale enhanced weathering processes actually doing what the scientists have suggested they will do.
In addition, the direct air capture (DAC) field is commercializing rapidly. Climeworks announced closing a commercial sales contract on a 1,000 t/yr plant in Germany, Carbon Engineering talked about getting close to inking commercial off-take contracts for solar fuels; Global Thermostat showed calculations showing how they could get below the $50/t price point for DAC CO2. The big caveat here is that DAC developers aren’t focusing on carbon removal in the short-term, as the markets for DAC sequestration aren't large enough. That said, many of the practitioners in the DAC companies that I spoke with expressed confidence that as soon as carbon prices (or other mechanisms for supporting carbon sequestration) rise considerably, DAC companies will have a clear path to delivering net-negative carbon emissions.
2. But there are still numerous uncertainties surrounding all of the carbon removal solutions, particularly around the sustainable scale potential. Biosequestration (e.g. reforestation, soil carbon sequestration, bioenergy with carbon capture and storage) still remains a highly uncertain prospect for carbon removal. Guy Lomax from the Nature Conservancy shared details of his most recent analysis that estimated that such biosequestration approaches are likely quite large, but not enormous – "you can't sequester the geosphere in the biosphere" was the quote that resonated the most with me from his talk. On the bioenergy with carbon capture front, scientists from Greenpeace and from DAC company Carbon Engineering alike shared the view that the sustainable biomass potential is likely constrained significantly,given the indirect land use considerations and potential competition for land with food crops. This view on biomass constraints doesn't seem to be shared with the climate modeling community: Andy Wiltshire from the UK Met Office shared that the average build out of bioenergy with carbon capture in modeling scenarios sequesters over 160 billion tons of carbon dioxide over the next century (equivalent to four times current emission levels today) -- which would involve bioenergy production on land larger than all of India.
3. The policy and governance conversation around carbon removal is fairly advanced – likely much further advanced than the actual solutions are themselves. This is both a good and bad thing. On the one hand, these discussions are critical for thinking through potential future impacts of carbon removal and how to provide incentives to scale up carbon removal solutions in an appropriate and ethical manner. On the other hand, because there are still so many uncertainties as to which solutions are even going to be viable, these discussions are founded on numerous hypothetical situations and assumptions, making it difficult to extract the most relevant conclusions. This is reflected most in the conversations where carbon removal was still conflated with solar geoengineering, much to the detriment of the overall conversation.
Conclusion: The impact of events like this will hopefully be to stimulate further research and collaboration – building the networks necessary for growth of the field. What’s needed now is to expand the conversation to involve new voices, scale up research, and get deployments happening. To this point, my favorite presentations was from Ned Garnett from the UK's Natural Environment Research Council, who shared his advice on how to get this research funded, telling the audience:
- Don’t just identify the problem, identify the innovative carbon removal research needed to address the problem;
- Identify any international development angles to carbon removal, as these are seen as higher priority in funders' minds today;
- Find independent forums to deliver advice; and
- It is critical to have a competitive process for awarding research grants in this field
Bottom line: a very interesting three days of carbon removal conversation in Oxford, and I look forward to more conferences in the future to continue to track the progress of the field and see how it grows over time.