Before we can zip around in zero-emission fuel-cell cars, the technology has to clear several roadblocks. Here’s how fuel cells work, how they’re being improved, and how long it will take before they hit the mainstream:

What’s the big deal?
Fuel cells have grabbed headlines and R&D dollars because they promise to ease pollution and petroleum consumption. A clean and quiet power source, fuel cells could someday power homes, cars and electronic devices more efficiently and with less pollution than conventional sources. They can run on pure hydrogen–a clean and abundant fuel–and release only water as a byproduct.

What are they exactly?
BusinessWeek recently likened fuel cells to tiny “chemical refineries.” These electrochemical energy conversion devices form water from hydrogen and oxygen and in the process, generate electricity and heat. Providing a DC (direct current) voltage, a fuel cell basically operates like a battery that can be recharged while it is generating power.

Fuel-cell markets fall under three general categories: 1) stationary (generators), 2) portable (electronic devices such as laptops, cellular phones and hearing aids) and 3) vehicle propulsion.

Brief history
In 1839, Sir William Grove combined hydrogen and oxygen, forming water and generating electricity. Today, fuel cells still work in essentially the same way. Their basic configuration consists of “two electrodes, a negative anode and a positive cathode, which are separated by a solid or liquid electrolyte that carries electronically charged particles between the two electrodes,” says Fuel Cell Today.

The U.S. government has been researching the benefits of the technology for more than half a century–with varying degrees of interest. After initial development, fuel-cell technology was largely ignored, overshadowed by the advent of the internal combustion engine and hindered by its limited practical application. But now, it has received renewed attention because of its environmental benefits and energy-saving potential.

Stumbling blocks?
Despite some inroads, mainstream use continues to elude fuel cells because of their high cost. According to a recent BusinessWeek article, “a fuel-cell system powerful enough for a car would add roughly $100,000 to sticker prices today.” Also tricky: storing and distributing hydrogen. An infrastructure of hydrogen refueling stations is a must, but less than 100 filling stations around the world supply hydrogen so far, according to BusinessWeek.

To address the hydrogen issue, a device called a reformer is usually employed. It converts hydrocarbon or alcohol fuels into hydrogen, which then enters the fuel cell. Reformers are problematic, however, creating heat and producing other gases along with hydrogen. Although several devices can help reformers clean up the hydrogen, they still produce impure hydrogen and greatly reduce the fuel cell’s efficiency–a huge issue for powering vehicles.

Meanwhile, when in comes to providing energy for portable products, tiny fuel cells have to tackle several critical issues, says a recent Design News article. These include standardization, energy density, and methanol crossover, says Sara Bradford, a Frost & Sullivan analyst.

On the bright side…
Fuel cells can extract hydrogen from such fuels as natural gas, propane and methanol. Many homes are already equipped with natural-gas lines or propane tanks so these fuels are very promising for home fuel cells. Meanwhile, methanol, a liquid fuel, can be easily transported and distributed, making it a contender for fuel-cell cars. In fact, for small fuel cells for electronic devices, methanol is already being positioned as the fuel of choice. Such micro fuel cells are set to debut on the market this year.

Meanwhile, to boost efficiency, some firms are forgoing the reformer entirely by developing advanced storage devices for hydrogen. Also, much progress has been made in increasing the fuel cell’s power density through engineering and material advances. Today, fuel cells can pack more power in smaller spaces. Now a device no bigger than a compact piece of luggage can run a car.

Forecast
According to Design News, this year will mark the “coming-out party” for micro fuel cells in portable products, such as laptops and industrial mobile-computing devices. But we may have to wait a couple of decades before fuel-cell cars can become mainstream enough to help reduce pollution or our dependence on petroleum, says BusinessWeek.

Sources:

Micro Fuel Cells: A Coming-Out Party in 2005
Randy Frank
Design News, January 10, 2005
www.designnews.com/article/CA491477.html

Hydrogen Cars Are Almost Here, But…
Otis Port
BusinessWeek, January 24, 2005
www.businessweek.com

How Fuel Cells Work
Karim Nice
How Stuff Works
auto.howstuffworks.com/fuel-cell.htm/printable