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sensible_heat
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Natural gas to liquid hydrocarbons is nothing new. http://www.google.com/search?q=gas+to+liquids Maybe they are just trying to do it in one step, which might lead to an improved process. Seems to be mostly marketing so far.
@Dave Kelly - I agree this does not appear to be the most feasible way to recycle CO2 into fuels. But that does not mean research should not continue on the process (you yourself should certainly not invest if it does not look promising; I do not plan to either). @Will S - The EROEI is most likely similar to PV, e.g. high. You invest energy in building the system, then you collect free energy for its lifetime, which quickly "pays back" for the energy you invested. It will not use waste heat to run the system since it needs heat at 1400 oC or whatnot. Why would you need to use waste heat to come out greater than unity?
@Alain - You are completely right! Except for how you use the term "catalysts" - In the case of this process, the solid redox materials used are part of the reaction, for example they split CO2 or H2O to CO or H2 by oxidizing iron to iron oxide in one step (transferring the oxygen atom), then reduce the iron oxide back to iron in the high temperature step, releasing oxygen (they actually use mixed-metal oxides with iron and other metals, but this is just an example). @HealthyBreeze - Synthetic photosynthesis type processes are much more efficient than natural photosynthesis. The best land-based biomass is around 1% efficient in sunlight-to-chemical energy and biofuels from traditional crops like corn are closer to 0.2%. I can provide references if desired (or just look it up). Even with commercially available photovoltaics (10-20% efficiency) and electrolyzers (60-80% efficiency) you are at 6-16% efficiency, so you will need about 1/10th the land of land-based biomass. Algae is a bit better but not as high as non-biological methods. @Engineer-Poet - There are certainly better CO2 sources, such as aluminum and other industrial plants, and CO2 captured from the atmosphere (http://www.scientificamerican.com/article.cfm?id=washing-carbon-out-of-the-air), but it is not completely ridiculous to use CO2 from a coal power plant. If you are running coal power plants you can either sequester the CO2 you have produced, or recycle it. To recycle it you obviously need renewable or nuclear energy. Solar electricity is not yet economical to replace the coal power plant. It is possible that their solar heat-driven process could be inexpensive enough to produce fuel (and would be competing with gasoline and biofuels, not with the electricity of the coal power plant). Heat is cheaper than electricity which is what attracts the researchers to such a process rather than electrolysis. Finally, at this stage there is no reason to believe this process will ever become economical, but the research should continue until it is clear whether or not it could be.
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Jun 2, 2010