hydrogen fuel cells:the power of tomorrowBY ALLEN DEARMOND AND LAUREN CUMMINGS

Generates electric power using a fuel and an oxidant Unlike a battery, chemicals are not stored in the fuel

cell; they must be replenished Possible fuel sources: hydrogen, alcohols, hydrocarbons, gasoline Possible oxidants: oxygen, chlorine, chlorine dioxide Refueling of an internal combustion engine, efficient and quiet like a battery

what is a fuel cell?

types of hydrogen fuel cells Polymer Electrolyte Membrane (PEM)

Fuel Cells Direct Methanol Fuel Cells Alkaline Fuel Cells Phosphoric Acid Fuel Cells Molten Carbonate Fuel Cells Solid Oxide Fuel Cells Regenerative Fuel Cells

science of hydrogen fuel cells Anode (-) and Cathode (+) on each side of the fuel

cell, divided by an electrolyte Hydrogen gas is channeled through anode side;

oxygen passes through cathode Platinum catalyst oxidizes hydrogen atoms into H+

and electrons Electrons pass along external circuit; conduct

electricity before entering cathode Electrolyte allows H+ to pass into the cathode In cathode, catalyst combines H+ , O2- and

electrons, forming H2O and heat

science of hydrogen fuel cells Anode:

2H2 => 4H+ + 4e-

Cathode: O2 + 4H+ + 4e- => 2H2O

Net Reaction:2H2 + O2 => 2H2O

Exact opposite of electrolysis

science of hydrogen fuel cells

optimization of fuel cells Catalyst: increases rate of reaction without

being consumed in the process Platinum is main catalyst used in PEM fuel

cells Platinum is expensive and highly sensitive to

poisoning New platinum/ruthenium catalysts being

researched for use in hydrogen fuel cells Reaction requires lower temperatures and

high humidity and pressure

present-day applications Little-to-no pollution, doesn’t need to be recharged 2500 fuel cell systems have been installed globally Used to power landfills and water treatment plants 50 fuel cell buses Every major automotive manufacturer has

designed a fuel cell-powered vehicle Mercedes-Benz projects 40% efficiency in compact

cars running on Hydrogen fuel cells Hydrogen Fuel Initiative (2003)

present-day applications

present-day applications Fuel cells require specific humidity, pressure,

etc. Catalysts are pricey and sensitive to

poisoning Difficult to produce hydrogen Difficult to store optimum amounts of

Hydrogen If fuels other than hydrogen are used, some

greenhouse gasses are emitted Very few cars currently running on hydrogen

the future of fuel cells Used to power personal electronic devices: cell

phones, iPods, laptops Enough energy to run for days, or weeks (instead

of hours) Potentially power all cars, airplanes, ships, etc. 60 million tons of carbon dioxide could be

eliminated from yearly greenhouse gas production

Development of cheaper and more reliable catalysts

Higher demand = cheaper

the future of fuel cells Economic crisis has greatly slowed

technological advancements Past predictions for 2010 seem unlikely Hydrogen cannot be the only alternative

fuel source to solve the energy crisis Many more years of research before

mass production will be possible

conclusion Hydrogen fuel cells are efficient, and

clean Also expensive, and require specific

humidity, temperature, pressure With more technological advancements,

could be used in mass production for various applications

Not an instant fix for the energy crisis, but definitely a major component

works cited Basic Elements: Fuel for the Future. Miramar High School. 3

March 2009. <http://library.thinkquest.org/04apr/00215/energy/fuel_cells/fuel_cells.htm>

Fuel Cells. Princeton University. 3 March 2009. <http://www.princeton.edu/~chm333/2002/spring/FuelCells/>

Fuel Cells. U.S. Department of Energy. 9 March 2009. <http://www1.eere.energy.gov/hydrogenandfuelcells/fuelcells/fc_types.html>

Hydrogen.gov United States Government. 10 March 2009. <http://www.hydrogen.gov>.

Nice, Karim and Jonathan Strickland. “How Fuel Cells Work.” 18 September 2000. How Stuff Works.com. <http://www.howstuffworks.com/fuel-cell.htm 3 March 2009>.