By Dr. James Hansen
There is enough popular misinterpretation of recent news about the cost of carbon capture that I should comment on that.
David Keith has done some of the most credible work on direct air capture of CO2, so his recent paper1 in Joule reporting on the cost of carbon capture deserves attention. Media reports emphasized that these reported costs were lower than costs estimated in a report by the American Physical Society (APS) in 2011. This caused some people to believe that we may be on the way to a “get out of jail free” card, the hope of many that technology will come to the rescue, so we do not need to be so concerned about the mess we are leaving for young people.
Unfortunately, the new news on carbon capture costs provides no support for the notion that we can solve the climate problem without fossil fuel phase-out. On the contrary, the Keith et al. study reinforces our concerns.
Many people failed to notice the matter of units. Keith reports a cost of $113-232 per ton of CO2 for plant designs in which the resulting CO2 is ready for sequestration. The cost per ton of carbon (tC) is higher by the factor 44/12. So the reported cost is $414-850/tC.
Furthermore, none of the four cases include the cost of carbon storage! According to the 2015 National Academy of Sciences report on CO2 removal2, the costs of geological sequestration are $37-73/tC. So the total costs for capture plus storage would be $451-923/tC.
Note that we used the cost range $113-232/tCO2 from the Keith paper. They also give a cost range $94-232/tCO2, which is what the media picked up on. However, the $94 case has the CO2 being used to make a liquid fuel that, when burned, puts the CO2 back in the air! So there is no negative emission. In fact, that total process would have positive emissions, at least to some degree.
In Young People’s Burden3, we were aware that the cost estimates from the APS study were high. Based on many studies referenced in our paper, we chose $150-350/tC as an optimistic estimate of the potential future cost. The low end of the cost range $451-923/tC based on Keith et al. is about 30% higher than the upper end of our range!
In Young People’s Burden we show that even our very optimistic cost of carbon capture results in an unbearable debt for young people, if high emissions continue unabated. The new estimates only reaffirm that conclusion. There is no prospect for a Get-Out-of-Jail-Free card.
One of the legal cases4 now underway is an effort to block the Trump government from opening up a huge new area of coal mining in Montana. The total coal resources in the basin in question are twice the quantity produced in the entire U.S. since 1949! Burning even a fraction of these resources would leave an astronomical cost for young people, as I show in the linked declaration5 I submitted to support the case against expanding that mining. It makes no sense to exploit these resources, serving only to enrich a handful of people. Most of the coal would be shipped to the Far East, but, in the end, I do not believe that the United States can escape either the moral or legal obligations from such a willful disregard of the consequences for young people. It makes no sense to approve such expansion of coal mining, and I believe that chances of blocking that expansion are good.
James Hansen, former director of the NASA Goddard Institute for Space Studies, is director of the Climate Science, Awareness and Solutions program at the Columbia University Earth Institute.
Footnotes and Links:
1 Keith, D.W., et al.: A Process for Capturing CO2 from the Atmosphere, Joule, 2, 1-22, 2018.
2 National Academy of Sciences: Climate Intervention: Carbon Dioxide Removal and Reliable Sequestration, Washington, D.C., 154 pp., https://doi.org/10.17226/18805, 2015
3 Young Peoples Burden: https://www.earth-syst-dynam.net/8/577/2017/
4 Montana Environmental Information Center v. U.S. Office of Surface Mining and Signal Peak Energy, LLC. Doc. 86.
5 Hansen Declaration: http://www.columbia.edu/~jeh1/2018/Hansen.2018.MontanaDeclaration.pdf