Physical chemist and entrepreneur John Morgan wrote a fascinating post for Brave New Climate in January. The possibilities of the US Navy and Palo Alto Research Center (PARC) research underscore the importance of innovation to deliver energy and especially transport fuel solutions that are workable (i.e., solutions that are compatible with Roger Pielke’s Iron Law).
The seawater CO2 extraction is a big win if the costs hold at scale, because the costs look to be MUCH lower than direct air capture. If the huge energy inputs required are supplied by nuclear (especially if the nuclear supply includes 800C process heat via high temperature gas reactor), then the synfuel is long-term carbon neutral. Innovation in direct air capture is still extremely important because it is clear that the planet will greatly exceed current carbon goals before it becomes truly zero carbon.
Two papers published last year described a new approach to zero emissions synfuel, looking at direct carbon dioxide extraction from seawater. The new insight in these papers is that CO2 is very soluble in seawater, where the concentration is about 140 times higher than in the atmosphere. This could make seawater extraction a lot cheaper than direct air capture.
Please read John’s entire post – it is well-sourced and well-written, and I believe accurate.