In twenty years, will you still be driving a car with an internal combustion engine? Not if the future unfolds the way auto industry experts expect it to.
The car of 2020, it seems increasingly likely, will be fueled with methanol or hydrogen and driven by an electric motor powered by fuel cells–most likely, fuel cells developed and perfected by a Canadian company.
There’s been a flurry of fuel cell activity recently. On October 30, Ford announced it will offer the first commercial fuel-cell-powered vehicles, based on the Ford Focus and intended for business fleets, in 2004. Fuel-cell-powered cars for the general consumer should be ready by 2010.
Then, on November 1, energy companies and government officials in Sacramento, California, unveiled a hub (a complex including garages and a hydrogen refueling station) that will service 70 cars and buses powered by various types of fuel cells.
It’s not surprising California is the focus for testing fuel cell technology, because a major boost to fuel-cell research was California’s legislated target that 10-percent of all vehicles sold in the state by 2003 be zero- or low-emission vehicles, and depending on the fuel used, fuel cells produce little or no pollution.
That’s because fuel cells, like batteries, produce energy through a chemical reaction, rather than combustion–but fuel cells never run down. They produce electricity as long as they are supplied with fuel..
A fuel cell consists of two electrodes sandwiched around an electrolyte (a substance that conducts charged particles). Oxygen (air) passes over one electrode (the cathode) and hydrogen over the other (the anode). A catalyst on the anode encourages the hydrogen atom to split into a positively charged proton and a negatively charged electron. The proton passes through the electrolyte, while the electrons follow a different path, producing an electrical current. Eventually the electrons return to the cathode, where they are reunited with the protons to create hydrogen, which in turn combines with the oxygen to create water. As a result, the only thing that comes out of the tailpipe of a fuel-cell-powered vehicle is warm, moist air.
The ideal fuel would be pure hydrogen, but the first practical fuel-cell-powered cars will likely will be powered by methanol, instead, which is easier to store and distribute. An additional piece of equipment called a reformer removes hydrogen from the methanol, producing a small amount of carbon dioxide in the process–but far less than an internal combustion engine.
The first fuel cell was built in 1839 by Sir William Grove, a Welsh judge and amateur scientist. However, they weren’t well known until the1960s, when NASA started using them aboard the Gemini and Apollo spacecraft. Fuel cells still provide electricity and water on the space shuttle.
Fuel cells are distinguished by the type of electrolyte they use. Some operate at very high temperatures –for instance, molten carbonate fuel cells operate at 650 degrees Celsius, and solid oxide fuel cells at a whopping 980 degrees. The higher temperatures make these fuel cells very efficient, but also impractical for automobiles.
The fuel cells being developed by Canada’s Ballard Power Systems for use in cars operate at a more manageable 92 degrees Celsius. Called proton exchange membrane fuel cells, they have a very thin layer of electrolyte between two platinum-coated electrodes. Each cell produces about 0.6 volts, which doesn’t sound like much, but because they’re so thin, they can be combined into stacks to produce as much power as you want.
The cells have been getting smaller and smaller. In 1994 the first full-sized automobile to use the Ballard fuel cells, the NECAR 1 (New Electric Car), developed by Daimler-Benz (now DaimlerChrysler, was a Mercedes-Benz van in which the hydrogen supply and fuel cells took up all of the cargo area. The fuel-cell stack now down to the size of a suitcase, and if methanol is used, the fuel tank is comparable in size to an ordinary gasoline tank.
Even before fuel-cell-powered automobiles become commonplace, we can expect to see fuel-cell-powered buses. The Chicago Transit Authority and BC Transit have both been testing fuel-cell-powered buses in their fleets, and providing valuable feedback. (Riders like the buses because they’re quiet and don’t stink; drivers find them a little sluggish, but that should improve as the technology advances.)
Promising near-zero emissions and comparable performance to internal combustion engines–not to mention relief from high gasoline prices–fuel-cell engines are the way of the future.
Your current vehicle may well be the last gas-burner you ever own.
