Hydrogen Fuel Cells as an Alternative Automobile Power Source

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Hydrogen Fuel Cellsas an Alternative Automobile
Power Source

• By Kenneth Noyce
• Physics 3150
• Energy and Sustainability

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Questions to be answered

• What is a Fuel Cell?
• How does a Fuel Cell work?
• How can a Fuel Cell be used in a car?
• What are the advantages of a Fuel Cell?
• What are the disadvantages of a Fuel Cell?
• How efficient would a Fuel Cell car be?

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What is a Fuel Cell?

• An electrochemical conversion device
• A better known electrochemical conversion
  device is a battery.
• A Fuel cell is a thermodynamically open system
  whereas a Battery is a closed system.

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What is a Fuel Cell?

• A fuel cell such as the one pictured to the
  right converts chemical potential energy stored
  in the fuel into electrical energy through a
  process of oxidation of the fuel.

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How does a Fuel Cell work?

• 1. Hydrogen fuel is broken into positive
  hydrogen ions and Negative electrons.
• 2. The hydrogen ions pass through an electrically
  insulating membrane which forced the electrons
  through an external circuit.
• 3. The Hydrogen ions and electrons then react
  with oxygen to form water as a byproduct.

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How does a Fuel Cell work?
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How can a Fuel Cell power a car?

• Currently there are 2 types of automobile
  engines, Internal Combustion, and Electrical. A
  fuel cell can be used to power an electrical
  engine similarly to how gasoline is used to power
  an internal combustion engine.

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How can a Fuel Cell power a car?

• Car would have a hydrogen tank rather than a gas
  tank.
• The chemical energy stored in the hydrogen would
  be converted into electrical energy in the fuel
  cell.
• The electrical energy produced by the fuel cell
  would power the cars electric motor.

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What are a Fuel Cells Advantages?

• Emissions
• Water is the only emission produced by a Fuel
  Cell
• Fuel availability
• Hydrogen comes from electrolysis of water
  which is a readily available substance.

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What are a Fuel Cells advantages?

• Reusability
• A fuel cell has an extremely long life unlike
  the batteries used to power current electrical
  cars
• Motor Efficiency
• Electric motors can easily achieve 90
  efficiency whereas internal combustion engines
  are typically only 30 efficient.

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What are a Fuel Cells disadvantages?

• Cost
• Fuel Cells are currently very expensive
  (2000-20000/kW) due to both their platinum
  content and production costs.
• Weight
• Fuel cells are much heavier than batteries
  with the same power output.

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What are a Fuel Cells disadvantages?

• Operating Temperature
• Most Fuel Cells cant operate at temperatures
  below freezing.
• Energy content of Hydrogen
• Hydrogen production requires more energy than
  is stored in the hydrogen making it an energy
  storage fuel.

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How efficient is a Fuel Cell?

• Fuel Cells range from 50 to 80 efficient
  depending on the operating temperature, and the
  current drawn from the fuel cell.
• Hydrogen production through electrolysis can
  obtain 80 efficiency.
• Electrical motors can attain 95 efficiency.

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How efficient is a Fuel Cell car?

• The maximum theoretical efficiency of a Fuel
  Cell powered vehicle from hydrogen production to
  driving assuming 10 losses due to friction is
• µ .8 x .85 x .95 x .9 .59 59 efficient
• The actual efficiency would be less than this,
  but would still be much higher than the average
  10 efficiency of most cars on the road today.

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References

• www.wikipedia.org
• www.bp.com
• www.hydrogenhighway.ca.gov
• www.shell.com

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Questions?