The second week of February, 2015, proved to be a busy week in all things carbon dioxide removal (“CDR”). First and foremost, the National Academy of Sciences came out with an extensive report on CDR that garnered significant media attention (including my own). The full report is worth the read, but if you only read two lines, I'd recommend the following in terms of importance for the CDR field:
"Even if CDR technologies never scale up to the point where they could remove a substantial fraction of current carbon emissions at an economically acceptable price, and even if it took many decades to develop even a modest capability, CDR technologies still have an important role to play.”
“If carbon removal technologies are to be viable, it is critical now to embark on a research program to lower the technical barriers to efficacy and affordability while remaining open to new ideas, approaches and synergies.”
Second, a great article was published in Nature Climate Change on the potential for bioenergy with carbon capture and storage ("bio-CCS") to generate net-negative electricity for the Western US. A summary of the report is available from UC Berkeley, and the research has garnered considerable outside media coverage. The biomass fuel supply curve developed by the report's authors is particularly interesting, and suggests that 100MM+ ton CDR from bio-CCS is possible in the western US largely from waste and residue feedstocks (which hold the potential to be more sustainable than dedicated feedstocks, assuming wastes aren't valued for other competing uses...).
Above: Biomass supply curve in Western US from Nature Climate Change "Biomass enables the transition to a carbon-negative power system across western North America"
Third, the AAAS Annual Meeting hosted a session titled, “Going Negative: Removing Carbon Dioxide From the Atmosphere” that looked into a wide range of CDR-related issues. The highlights from the session included:
- Pete Smith from the University of Aberdeen kicked off the session with the conclusion that there is no magic bullet for CDR – pros and cons exist for all approaches – and that more RD&D is needed to develop viable CDR approaches. In addition, Pete noted that sustainability will be critical for developing CDR solutions, and that a negative emission technology strategy will have to develop hand in hand with food-, water-, and biodiversity-security strategies.
- Jen Wilcox from Stanford summarized some of the key findings from the NAS report on CDR. One of the more interesting results she highlighted was from a paper she authored that estimated the amount of CDR potential in the existing fly ash, cement kiln dust, and iron/steel slag industries today -- which could present low-hanging fruit for turning today's industrial wastes into valuable inputs for tomorrow's CDR process (even though the study finds that such industrial sources represent about 0.1% of total US emissions). More importantly, Jen highlighted that CDR and CCS technologies share a number of open research questions, and could benefit from an overlapping research agenda.
- Peter Byck from ASU presented his video Soil Carbon Cowboys and discussed the exciting scientific research his team is planning to conduct to assess the potential of adaptive management practices of livestock rearing. And Lisamarie Windham-Myers from the USGS shared her work with soil carbon sequestration, highlighting groups like the Marin Carbon Project.
- The final two presentations of the session, from Ken Caldeira of Carnegie Institution for Science and Jae Edmonds of Joint Global Change Research Institute, provided an interesting point of conclusion for the session. In particular, Jae's work showed that integrated assessment models of energy systems enthusiastically build bio-CCS projects as a means to decarbonize the energy sector. Bio-CCS (as well as its cousin direct air capture and sequestration, or "DACS") are highly industrial systems, which contrast greatly to the ranching and "carbon farming" techniques highlighted by Peter and Lisa Marie in the previous two sessions. The industrial CDR approaches lag far behind the biological approaches in terms of early enthusiasm outside of the academic community, and it will be critical for these industrial approaches to find an enthusiastic supporter base in industry (or elsewhere) for them to gain traction and meet the promise identified in the integrated assessment models.
Fourth and finally, interesting CCS innovations were on display at the ARPA-E conference in DC. Such innovations from ARPA-E programs like IMPACCT will prove critical for enabling both fossil and bioenergy CCS projects in the future. CCS was only a small fraction of the overall ARPA-E conference, and the session dedicated to CCS focused on the nascent market for utilizing CO2 in industrial applications. I am hopeful that the ARPA-E conferences in the future will highlight more innovations with shared CDR applications, including direct air capture, gasification, and thermochemical biomass conversion technologies.