Carbon-Neutral Liquid Fuel
Vehicle-compatible, scalable, and cost-competitive energy storage
PARC is developing a commercially viable approach to making carbon- neutral liquid fuel from sunlight and seawater that has the potential to be cost-effective, scalable, efficient, and, most important, realizable within the existing fuel infrastructure.
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Using hydrogen or electricity to power our transportation system requires constructing entirely new vehicle and fuel infrastructures. A more desirable solution would be to develop infrastructure-compatible liquid hydrocarbons. While biofuels present a possible solution, deploying biofuels on a global scale is difficult because of the land-area requirements. Approaches that take the “bio” out of biofuels are therefore very attractive.
PARC’s non-biological approach for producing liquid fuels is feasible for wide-spread deployment, and has the potential to compete with fossil-fuel prices.
Advantages to PARC’s approach include:
- Reducing CO2 emissions from automobiles and airplanes (replacing 50% of U.S. motor gasoline and jet fuels with carbon-neutral fuel would prevent 710 million metric tons of CO2 emissions)
- Enabling an increase in the production of renewable energy by storing excess renewable energy in vehicle- compatible fuels
Atmospheric capture of CO2 as a carbon source for renewable synthetic hydrocarbons has been explored, but the large air contactors required render this method, so far, prohibitively expensive. To avoid this barrier, we propose a completely different approach: extracting CO2 from the sea. Seawater contains a vast resource of CO2, in equilibrium with the atmosphere but at higher concentration than is found in air. CO2 can therefore be extracted from seawater without the large- area contactors required for direct atmospheric capture.
PARC, in work performed for DARPA*, has recently demonstrated that bipolar membrane electrodialysis can be used to extract CO2 from seawater in a process with the potential to achieve very high efficiency (see Eisaman et al., Energy Environ. Sci., 2012 DOI: 10.1039/ C2EE03393C). As long as the energy for the process is renewably produced, the overall process is carbon-neutral since the CO2 released into the atmosphere when the fuel is combusted was originally captured from the atmosphere by the sea.
To fully realize the potential of our innovation, we are seeking additional funding and/or commercialization partners to build a complete end-to-end renewable fuel prototype unit.
*This work was supported by DARPA contracts NBCHC090074 and HR001-10-C-0147. The views, opinions, and/or findings contained in this article/ presentation are those of the author/presenter and should not be interpreted as representing the official views or policies, either expressed or implied, of the Defense Advanced Research Projects Agency or the Department of Defense. Content of this datasheet has been approved for public release, distribution unlimited.