Generators, Motors and How We Get Electricity

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Generators, Motors and How We Get Electricity
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Topics

• What is electricity?
• Energy Conversion
• The Faraday Effect
• Motor vs. Generator
• AC/DC
• Energy Trends - the case for Green

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What is Electricity?
Electricity is energy transported by the motion
of electrons
We do not make electricity, we CONVERT other
energy sources into electrical energy
Conversion is the name of the game
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Energy Conversion Options for ElectricityNon-Ther
mal Paths

•  Source to Electrical
•  
• Source Converter
• Sun Photovoltaic (photon to electron)
• Chemical Fuel Cell
•  
• Source to Potential/Kinetic to Mechanical to
  Electrical
•  
• Source Converter Kinetic to Mechanical Mech to
  Electrical
• Dam Penstocks Turbine (water) Generator
• Tides Machine Turbine (air or water) Generator
• Wind N/A Turbine (air) Generator

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Energy Conversion Options for ElectricityThermal
Paths

•  Heat to Mechanical to Electrical
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• Source Heat to Mechanical Mech to Electrical
• Geothermal Turbine (vapor) Generator
• OTEC Turbine (vapor) Generator
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• Stored Energy to Heat to Mechanical to
  Electrical
•  
• Source Reactor Heat to Mechanical Mech
  to Electrical
• Fuel Combustor Turbine (gas or vapor) Generator
• U, Pu Reactor Turbine (gas or vapor) Generator
• Sun Collector Turbine (gas or vapor) Generator
• H, H2, H3Reactor Turbine (gas or
  vapor) Generator
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• More a modifier or concentrator than a reactor

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Faraday Effect
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Electric Motor
M
Electrical Energy
Mechanical Energy
DC Motor
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Model Electric Motor
Beakman Motor

1. Electric Energy
2. Coil
3. Magnetic Field

What do you need?
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Electric Generator
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Mechanical Energy
Electrical Energy
Stationary magnets - rotating magnets -
electromagnets
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AC/DC (not the band)

• Alternating Current
• Large-scale generators produce AC
• Follows sine wave with n cycles per second
• 1, 2, 3-phase?
• US120 V,60 Hz
• Europe 240 V,50Hz
• Transforming ability

• Direct Current
• Batteries, Photovoltaics, fuel cells, small DC
  generators
• Charge in ONE direction
• Negative, Positive terminals
• Easy conversion AC to DC, not DC to AC

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Generator Phases 1 Phase 2 Phase 3
PhaseSmooth Power
Force Driving Motor (Red)
Single Phase Two Phase
Three Phase
Polyphase Systems ? 3 phases for smoother torque
delivery
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Where do we get our Electricity?

• Fossil Coal, Natural Gas, Oil 550 Gigawatts
  (GW)
• Nuclear 200 GW
• Hydro 75 GW
• Geothermal 2.3 GW
• Other Renewable Wind, Solar, OTEC 13.6 GW

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Energy Usage Per Capita (1999)
TOE/person-year
TOE - Tons of Oil Equivalent (40 Million Btus)
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Oil Resources
Have Oil
Use Oil
Saudi Arabia 26 Iraq 11 Kuwait
10 Iran 9 UAE 8 Venezuela
6 Russia 5 Libya 3 Mexico
3 China 3 Nigeria 2 U.S. 2
U.S. 26 Japan 7 China 6 Germany
4 Canada 4 Russia 3 Brazil 3 S.
Korea 3 France 3 India 3 Mexico
3 Italy 2
The U.S. uses more than the next 5
highest consuming nations combined.
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U.S. Renewable Energy Resource Assessment
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Barriers to Change

• US energy infrastructure is large and deeply
  entrenched
• 400,000 miles of gas and oil pipelines
• 160,000 of high voltage transmission lines
• 176,000 gasoline stations
• 1000s of oil and gas wells drilled annually in
  the US and Canada

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Barriers to Change

• oil and gas are readily available as a world
  commodity at low cost -- equivalent to 4 to 5 /
  million Btu
• US coal is even more abundant and cheaper
  approximately 1/million Btu
• US electricity prices remain low relative to
  other commodities

The average American family spends only 3 to 4
of their income on energy!!