Analysis // Ben FrankelWater is key to the hydrogen economy

Here are two themes we have been writing about, combining to create a persuasive security argument and a compelling business proposition. The security argument has to do with lessening dependence on oil, the business propsition has to do with water (yes, water). Here goes: One way to enhance the security — and homeland security — of the United States and, for that matter, of many other countries, is to reduce these countries’ dependence on oil. One way to reduce the dependence on oil is to move toward what is called a hydrogen economy. What would a transition to a hydrogen economy entail? A lot of water, that’s what. Michael Webber, associate director at the Center for International Energy and Environmental Policy at the University of Texas at Austin, has published an interesting and useful study in Environmental Research Letters providing the first analysis of the total water requirements with recent data for a transitional hydrogen economy. The hydrogen economy is not exactly around the corner — the National Research Council (NRC) expects it to be here somewhere between 2037 and 2050). In its 2004 study, the NRC predicts an annual production of 60 billion kg of hydrogen. Webber estimates that this amount of hydrogen would use between 19 and 69 trillion gallons of water annually as a feedstock for electrolytic production and as a coolant for thermoelectric power. This amount transltes to 52 to 189 billion gallons per day, which is between 27 percent and 97 percent increase from the 195 billion gallons per day, 72 trillion gallons annually, used today by the thermoelectric power sector to generate about 90 perecnt of the electricity in the United States. During the past several decades, water withdrawal has remained stable, suggesting that this increase in water use intensity could have unprecedented consequences on the natural resource and public policy.

“The greatest significance of this work is that, by shifting our fuels production onto the grid, we can have a very dramatic impact on water resources unless policy changes are implemented that require system-wide shifts to power plant cooling methods that are less water-intensive or to power sources that don’t require cooling,” Webber told PhysOrg.com. “This analysis is not meant to say that hydrogen should not be pursued, just that if hydrogen production is pursued through thermoelectrically-powered electrolysis, the impacts on water are potentially quite severe.” Webber’s estimate