Sustainable Transportation Fuels From Off-Peak Wind Energy, CO₂, and Water

Doty Energy is developing advanced processes to permit the production of fully carbon-neutral gasoline, jet fuel, diesel, ethanol, and plastics from exhaust CO₂ and off-peak clean energy (wind and nuclear) at prices that can compete with fossil-derived products. Converting CO₂ into fuels will eliminate the need for CO₂ sequestration, reduce global CO₂ emissions by 40%, and provide a nearly insatiable market for off-peak wind. It has long been known that it is theoretically possible to convert CO₂ and water into standard liquid hydrocarbon fuels at high efficiency. However, the early proposals for doing this conversion had efficiencies of only 25% to 35%. That is, the chemical energy in the liquid fuels produced (gasoline, ethanol, etc.) would be about the 30% of the input energy required. The combination of the eight major technical advances made over the past two years should permit this conversion to be done at up to 60% efficiency. Off-peak grid energy averaged only $16.4/MWhr in the Minnesota hub throughout all of 2009 (the cheapest 6 hours/day averaged only $7.1/MWh). At such prices, the synthesized standard liquid fuels (dubbed “WindFuels”) should compete even when petroleum is only $45/bbl. A more scalable alternative for transportation fuels is needed than biofuels. It is in our economic and security interests to produce transportation fuels domestically at the scale of hundreds of billions of gallons per year. WindFuels can scale to this level, and as they are fully carbon-neutral they will dramatically reduce global CO₂ emissions at the same time. Switching 70% of global transportation fuels from petroleum to WindFuels should be possible over the next 30 years. WindFuels will insure extremely strong growth in wind energy for many decades by generating an enormous market for off-peak wind energy. WindFuels is based largely on the commercially proven technologies of wind energy, water electrolysis, and Fischer Tropsch (FT) chemistry. Off-peak low carbon energy is used to split water into hydrogen and oxygen. Some of the hydrogen is used to reduce CO₂ into carbon monoxide (CO) and water via the Reverse Water Gas Shift (RWGS) reaction. The CO and the balance of the hydrogen are fed into an FT reactor similar to those used to produce fuels and chemicals from coal or natural gas. The processes have been simulated, and key experiments are being carried out to help optimize process conditions and validate the simulations.