In the Jan/Feb 2003 issue of E Magazine, Jeremy Rifkin wrote an article "The Hydrogen Economy – After Oil, Clean Energy From a Fuel-Cell-Driven Global Hydrogen Web." After explaining that electricity is used to generate hydrogen, which is used to generate electricity, the article then proceeded to the next paragraph:

"People often ask: Why generate electricity twice, first to produce electricity for the process of electrolytic hydrogen and then again to produce electricity and heat in a fuel cell? The reason is that electricity can be stored only in batteries, which are cumbersome to transport and slow to recharge, while hydrogen can be stored at much lower cost. Internal-combustion engines capture only 15 to 20 percent of the energy in gasoline, and the conventional electric power grid is only 33 percent efficient. But as Amory Lovins' Rocky Mountain Institute (RMI) points out, 'Fuel cells can convert 40 to 65 percent of hydrogen's energy into electricity.'"

Mr. Rifkin notes that electricity can only be stored in batteries, which aren't very good, while hydrogen can presumably be stored at a lower cost. The cost comparison for generation of the electricity for the battery or hydrogen for the alternative is not provided.

His next sentence introduced the concept of inefficiency. ICE's (internal combustion engines) capture 20 percent of gasoline's energy and electric power plants are only 33 percent efficient. Would this mean that an electric power plant is more efficient than an ICE when charging a battery for an electric vehicle? Isn't this comparing an apple to an orange?

Next he quotes Amory Lovins, who says fuel cells can convert 40-65 percent of hydrogen's energy into electricity. Is this the same efficiency of the ICE and the power plant? Does that mean that a power plant operating on natural gas can generate electricity that, when converted to hydrogen to operate a car, is 3 times more efficient than a car burning the natural gas? (Natural gas has been used as a fuel for vehicles for years.) And does that mean that a car of the same weight when run by a fuel cell gets three times the mileage of an ICE using gasoline or natural gas? If the hydrogen is made from natural gas, is there more or less natural gas used for the hydrogen car than for an equivalent weight and efficiency ICE car using natural gas as the fuel?

A very important number is the cost of the electricity, generated by whatever process used, which is converted to the "form" of hydrogen. The December 2002 issue of BioScience Magazine contained an article entitled "Renewable Energy: Current and Potential Issues." The author, David Pimentel, notes "The energy required to produce 1 billion kWh of hydrogen is 1.4 Billion kWh of electricity." Later on the same page he says "The conversion of hydrogen into direct current (DC) using a fuel cell is about 40 percent efficient." One might conclude that this means 60 percent is wasted, or that, of the 1 billion kWh produced, only 400 million kWh is used. Using 1.4 billion kWh to produce 400 Million kWh in useful energy means a loss of about 70% of the original energy available.

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