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Fuel Cell Biology

Initially used in the ?60s by NASA to power space shuttles, fuel cells can potentially be adapted to provide electricity for everything from cars to laptops.

By ELLIOT CURRY

One car that consistently separates itself from all the rest is the concept car. Besides being beautiful, exotic and so technically advanced that the Batmobile looks like a 1980 Accord, the link among most of today?s concepts cars is their usage of the fuel cell as a power source.

By now, most people know what the fuel cell is and how it works, but a few misconceptions have perpetuated in recent years. A fuel cell is radically different from a battery, although the technology it employs is more than 150 years old. Initially used in the ?60s by NASA to power space shuttles, fuel cells can potentially be adapted to provide electricity for everything from cars to laptops. What makes the fuel cell such an important topic is its prospected role in initiating and sustaining independence from oil.

With current federal funding from the Department of Energy reaching nearly $82 million for the coming year, the fuel cell is intended to play a pivotal role in the future of domestic and foreign policy. When finally released to the masses, the fuel cell will represent a complete departure from our current philosophy of energy production. At the moment, the United States burns 20 million barrels of oil a day, and each year, a single passenger car emits 77.1 pounds of hydrocarbons and a staggering 575 pounds of poisonous carbon monoxide.

The fuel cell releases no harmful emissions -- its only by-product is pure water. With the increasing concerns over air pollution and the associated environmental and health risks, the implementation of the fuel cell represents a significant step in improving air quality and national health. In addition, a fuel cell is 10 to 30 percent more efficient than a combustion engine when used in an automobile.

A fuel cell is interesting in that it utilizes a very straightforward design. It?s merely composed of an anode (a negative electrode), a polymer electrolyte membrane and a cathode (a positive electrode), placed together in the respective order. Hydrogen is typically pumped into a chamber next to the anode, where a platinum catalyst breaks the hydrogen molecule into positively charged hydrogen ions and electrons. The ions are able to pass through the membrane to the cathode, while the electrons that were separated from the ions, longing to be with the cathode, travel through a circuit, thus powering the electric engine. The electrons then leave the engine and finally reach the cathode, where they react with the ions and oxygen that has been pumped from the air outside to produce water.

When paired with an electric engine, this simple design has less moving parts than the classic combustion engine, lending it a potentially longer lifespan. Because the fuel cell?s applications extend beyond cars, estimates are that it will be eventually used to run power plants, heat houses and power PDAs. While the future of this technology seems promising and close at hand, there?s a reason we?re only seeing the fuel cell in the concept car stage.

The dilemmas facing the fuel cell are not minute. Experts speculate that its inception into mainstream use won?t occur until 2020. Cost is currently the greatest obstacle. Each cell uses platinum as a catalyst to separate the hydrogen molecules, and since one cell produces only about 1.16 volts of electricity, multiple cells are needed to power a vehicle. It?s estimated that platinum reserves around the world are not large enough to support a mass conversion to the fuel cell in automobiles. Additionally, the anode and cathode, which are made by hand, are extremely difficult and costly to produce. The fuel cell of today costs nearly $4,500 per kilowatt. It?s estimated that the cost needs to drop to $400 per kilowatt for mass production to be profitable.

There?s currently no infrastructure for the transportation and sale of hydrogen. Even more concerning, car manufacturers have yet to produce a tank suitable for storing compressed hydrogen. Car manufacturers are working with metal hydrides and carbon composites, but continue to have difficulties creating a tank of adequate size that meets expected standards. There are further problems, including reaction difficulties in cold weather and most troubling, shortened lifespan under constant use in experimental trials.

In the late ?90s, the top car manufacturers estimated that they would have fuel cell vehicles in full production by 2002. In 2006, with none in production, realism has set in. While the fuel cell might in time be a saving grace, dependence on oil won?t be eliminated overnight by a currently ill-equipped innovation, no matter how eagerly it?s anticipated.

Published: April 01, 2006
Issue: Spring 2006