Tidal and wave energy sources come out as clear winners in their potentail as a green fuel source for the future in a paper published by Stanford professor of civil and environmental engineering, Mark Z. Jacobson. The best ways to improve energy security, mitigate global warming and reduce the number of deaths caused by air pollution are blowing in the wind and rippling in the water, not growing on prairies or glowing inside nuclear power plants, says Jacobson.

Jacobson says he has conducted the first quantitative, scientific evaluation of the proposed, major, energy-related solutions by assessing not only their potential for delivering energy for electricity and vehicles, but also their impacts on global warming, human health, energy security, water supply, space requirements, wildlife, water pollution, reliability and sustainability. His findings indicate that the options that are getting the most attention are between 25 to 1,000 times more polluting than the best available options. The paper with his findings will be published in the next issue of Energy and Environmental Science but is available online now. Jacobson is also director of the Atmosphere/Energy Program at Stanford.

To place the various alternatives on an equal footing, Jacobson first made his comparisons among the energy sources by calculating the impacts as if each alternative alone were used to power all the vehicles in the United States, assuming only "new-technology" vehicles were being used. Such vehicles include battery electric vehicles (BEVs), hydrogen fuel cell vehicles (HFCVs), and "flex-fuel" vehicles that could run on a high blend of ethanol called E85.

Jacobson said that while some people are under the impression that wind and wave power are too variable to provide steady amounts of electricity, his research group has already shown in previous research that by properly coordinating the energy output from wind farms in different locations, the potential problem with variability can be overcome and a steady supply of baseline power delivered to users.

Jacobson's research is particularly scathing about nuclear and clean coal. Notably, during the recent presidential campaign nuclear power and clean coal were often touted as energy solutions that should be pursued, but nuclear power and coal with carbon capture and sequestration were Jacobson's lowest-ranked choices after biofuels. "Coal with carbon sequestration emits 60- to 110-times more carbon and air pollution than wind energy, and nuclear emits about 25-times more carbon and air pollution than wind energy," Jacobson said. Although carbon-capture equipment reduces 85-90 percent of the carbon exhaust from a coal-fired power plant, it has no impact on the carbon resulting from the mining or transport of the coal or on the exhaust of other air pollutants. In fact, because carbon capture requires a roughly 25-percent increase in energy from the coal plant, about 25 percent more coal is needed, increasing mountaintop removal and increasing non-carbon air pollution from power plants, he said.