Introduction
History
Fuel Cell Concepts
Electrochemistry
Benefits and advantages
Challenges and potential ahead
Reference

Introduction:
U.S. energy dependence is higher today than it was during the "oil shock" of the 1970s. Currently, passenger vehicles alone consume 6 million barrels of oil every single day, which is 85% of oil imports. Fuel cells, a low emission, high efficiency and compact means of providing high quality of energy may be a solution to our problem and serve as a better alternative.

History:
Sir William Grove is widely attributed to the "Father of the Fuel Cell". Grove gained from his experiments in 1839 on electrolysis of water that there should be a possible process to reverse the separation of hydrogen and oxygen. In other words, reacting hydrogen with oxygen to generate electricity.

In 1889, the term fuel cell was introduced by Ludwig Mond and Charles Langer, who attempted to build the first practical device using air and industrial coal gas. However, all efforts were in vain as there lacked a understanding of materials and electrode kinetics. It was until 1932 when the first fuel cell device was invented by Francis Bacon. He improved on the expensive platinum catalyst employed by Mond and Langer with a hydrogen-oxygen cell using a less corrosive alkaline electrode and inexpensive nickel electrode.

About a quarter century later, in 1959, Harry Karl Ihrig demonstrated his famous 20 horsepower fuel cell powered tractor which is a significant improvement from Bacon's five kilowatt system capable of powering a welding machine. In addition, in the late 1950s, a little known federal agency back then called the National Aeronautics and Space Administration (NASA) began to search for a compact electrical generator to provide onboard power for an upcoming series of manned space missions. NASA discarded the options of using nuclear reactors, batteries and solar power as they were either too risky, too heavy and short lived or too cumbersome. Hence, NASA turned to fuel cells. Today, fuel cells have proven its role in space with the Apollo and Space Shuttle missions.
 
 

Fuel Cell Concepts:
Fuel cells make electricity by combining hydrogen ions, drawn from a hydrogen containing fuel, with oxygen atoms. The fuel cell uses these ingredients to create chemical reactions that produce either hydrogen -or oxygen bearing ions at one of the cells' two electrodes. These ions then pass through an electrolyte which conducts electricity, such as phosphoric acid or carbonate, and react with oxygen atoms. The result is an electric current at both electrodes, plus waste heat and water vapor as exhausts products. The voltage is limited to about 1.23 V per pair of electrode, but fuel cells can be stacked together until the desired amount of power level is reached.

Electrochemistry:

The oxidant (fuel and air) is fed to the cell's electrodes. Ions are transported through the electrolyte to create a current.
Overall reactions:
Natural Gas +Air => Steam + Carbon Dioxide + Electricity + Heat
Reforming Reactions:
Natural Gas + Steam => Hydrogen + Carbon Monoxide
Anode Reactions:
Hydrogen +Carbon Monoxide+Carbon Ions=> Steam +Carbon Dioxide+Heat +Electrons
Cathode Reaction:
Carbon Dioxide+Oxygen +Electrons=> Carbonate Ion

Benefits and advantages:
Fuel cells have several benefits, they are as follow. Fuel cell could dramatically:

1.  reduce urban air pollution- If 10% of automobiles nationwide are powered by fuel cells. Regulated air pollutants would be cut by one million tons per year and 60 millions tons of greenhouse gas (carbon dioxide) would be eliminated.
2. decrease oil imports by 800,000 barrels a day, an amount equivalent to 13% of total imports.
3. reduce the trade deficit
4. produce America jobs. Arthur D. Little projects that each 1,000 MW of energy created by fuel cells will create 5,000 jobs. If just 20% of the cars used fuel cells, 800,000 jobs would be created.

• Fuel cell power system markets could exceed $3 billion worldwide by 2000 and global demand for transportation fuel cells in 2007 will reach $ 9 billion.
• If just 205 of cars used fuel cells, oil imports could be reduced by 1.5 million barrels every day.
• If every new vehicle sold in the U.S. next year was equipped with a 60 kW fuel cell, the country's available electricity supply would double.
• 10,000 fuel cell vehicles running on non-petroleum fuel would reduce oil consumption by 6.98 million gallons per year.

References:
http://216.51.18.233fcbenefi.html-Fuel Cells 2000's Benefits of Fuel Cells Page
http://www.ttcorp.com/fccg-Fuel Cell Commercialization Group.
http://www.sciam.com/exploration/122396explorations.html-Scientific American: Explorations: Beyond Batteries: 12/96
http://www,nfcrc.uci.edu/fcinfo/what.htm-what is a fuel cell?