Fuel Cell Vehicles

According to HowStuffWorks.com, a fuel cell is an electrochemical energy conversion device that converts hydrogen and oxygen into electricity and heat. Fuel cells are essentially batteries that recharge themselves without needing to be plugged in. They draw their power from hydrogen and oxygen.

Most of today's fuel cells use a process called proton exchange. Simply put, hydrogen gas (H2) is pushed into the fuel cell, where it reacts with a catalyst inside and splits into two hydrogen atoms. The energy produced during the reaction is used to power the vehicle. Meanwhile, oxygen, specifically O2, is being pushed into the fuel cell from the other side. It also splits in two, and the resulting solo oxygen atoms combine with the hydrogen atoms in the following arrangement: H2O. Look familiar? It should - it's water. That's the beauty of the fuel cell: once the fuel (hydrogen gas) has done its work, the only byproduct (the "exhaust" or "pollution") is distilled hot water. Put a bunch of fuel cells together and you have a fuel cell stack (size = small suitcase), which is really what's needed to produce enough power to run a car. The stack goes in the front of the car and replaces most of the standard internal combustion engine components.

Although Easy Breathers is focusing on fuel cells as power for transportation, they're also being developed for "stationary use" in buildings. So you power the building with fuel cells, which gives you an electricity source on site, and then your byproduct, distilled hot water, is simply the hot water for the building! Cool.

Here's what that electrochemical reaction we mentioned looks like (simplified): 2H₂ + O₂ => 2H₂O

• 2H₂ is 2 molecules of diatomic Hydrogen
• O₂ is one diatomic Oxygen molecule
• and 2H₂O is 2 molecules of water

Like electric vehicles, fuel cells vehicles are quiet and clean. Unlike EVs, they don't need to be plugged in to recharge their batteries. However, they do need fuel - they need hydrogen. The oxygen used in the fuel cell is pumped in straight from the outside air. Getting hydrogen is trickier, especially if your main goals are pollution reduction and efficiency.

Efficiency
A fuel cell powered by 100 percent hydrogen is about 80 percent efficient, meaning that about 20 percent of the potential energy of the hydrogen is lost during the reaction. Since hydrogen isn't really available at your local gas station, most fuel cells use a reformer, which is a piece of equipment that extracts hydrogen from conventional types of fuels like methanol or gasoline. Unfortunately, using a reformer cuts the efficiency of the operation down to between 25 and 30 percent. That's a little better than our gas-powered cars today, which are a dismal 20 percent efficient. Battery-powered electric cars vary between 25 and 65 percent efficiency - depending on how the electricity used to charge the batteries was generated. Number cruncher? Check this page to see where we got the stats: http://www.howstuffworks.com/fuel-cell4.htm.

So when can you buy a fuel cell vehicle?
If the vehicle fleet of the future is to rely on fuel cells, developers have to come up with a safe, efficient, reliable way to manufacture, store, transport, and distribute the fuel. For hydrogen fuel cells, that could mean converting existing gasoline/diesel stations to hydrogen stations. It could mean using natural gas from the line already at your house to fill up the reformer in the vehicle with natural gas. Or any number of other possibilities...

Fuel cell technology is very promising, even though it has challenges. Every major auto manufacturer is currently conducting or investing in fuel cell research, and most industry experts see fuel cell vehicles as the transportation of the future. Prototype and test vehicles abound, but estimates on when fuel cells might be manufactured on a large scale put the timeline at about 2010 to 2040.

More information
This profile of fuel cells really only scratches the surface. To learn more, check out these sites:

HowStuffWorks.com explains fuel cells in more detail, with handy diagrams: http://www.howstuffworks.com/fuel-cell1.htm

Ford Motor Company explains fuel cells and gives you a tour of their prototypes at http://www.thinkmobility.com/tech_fueloverview.asp?TID=527465.

The Hypercar™ prototype, the "Revolution," is a hybrid-electric vehicle powered by a fuel cell. Read more about it on this site: http://www.hypercar.com.

Fuel Cells 2000: The Online Fuel Cell Information Center: http://www.fuelcells.org/.