Introduction: Energy Unit

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Introduction Energy Unit

• Technology Foundations
• Stuarts Draft High School

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Energy

• Energy creates the power to drive tools and
  machines, to process materials into manufactured
  products and to create structures.
• Power is generated from nonrenewable energy
  sources such as coal, oil, and gas, or can be
  generated from natural resources such as
  geothermal, solar, and gravitational energies.

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Classifications of Energy Sources
Unlimited Solar Wind Gravitational Tidal Geotherma
l Fusion
Renewable Wood Biomass Gasification Biomass
Fermentation Animal Power Human Muscle Power

• Limited
• Oil
• Coal
• Natural gas
• Uranium

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NONRENEWABLE RESOURCES

• COAL
• Although coal is found in many places throughout
  the world, nearly half of it is located in the
  United States. Of the 700 million tons of coal
  mined each year in the United States, two- thirds
  is burned to fuel electric generating plants. The
  remainder is used to provide heat for buildings
  and to make steel and other industrial products.

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NONRENEWABLE RESOURCES

• GEOTHERMAL POWER
• Geothermal energy comes from the tremendous heat
  trapped deep within the earth. Natural steam
  geysers are used to generate electricity. Hot
  water can also be pumped out of the ground to
  heat buildings. Geothermal sources account for
  less than 1 of the total energy produced In the
  United States. Most of the sources are in the
  western third of the nation.

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NONRENEWABLE RESOURCES

• NATURAL GAS
• It is estimated that there is only enough natural
  gas in the world to last for 20 more years. Most
  of the recoverable supplies are found In the
  U.S.S.R., the Middle East, and the United States.
  Natural gas provides about 32 of the total
  energy used in the United States. Some natural
  gas is used for home heating and cooking, but
  most is used in industry.

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NONRENEWABLE RESOURCES

• NUCLEAR POWER
• Nuclear power requires uranium as the fuel
  source. When uranium atoms are split (fission),
  heat is released. Water is circulated through the
  reactor to keep it cool. As the water turns to
  steam, it is forced through a turbine to generate
  electricity. There are 52 nuclear generating
  plants, which provide about 1 of our total
  energy in the United States.

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NONRENEWABLE RESOURCES

• OIL
• Oil is a fossil fuel that is recovered by
  drilling wells either on land or from offshore
  rigs. The world produces about 20 million barrels
  of all each year - one-third of which is used by
  the United States. Only about 35 of the oil in a
  well can be recovered. Some oil is used to heat
  buildings and to generate electricity. The
  remainder is distilled (cooked) to produce
  gasoline and other by-products.

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RENEWABLE RESOURCES

• BIOFUELS
• Biofuels are organic (once-living) matter such as
  trees, sugarcane, corn, manure, and seaweed. Some
  of these organic materials can be burned directly
  to produce heat. Others are converted into
  flammable liquids or gases. Corn can be distilled
  to produce methanol, which is then mixed with
  gasoline to produce gasohol. Biofuels provide
  about 2 of our energy in the United States.

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RENEWABLE RESOURCES

• WATER POWER
• Moving water holds a tremendous amount of
  potential energy. Dams are built to direct
  failing water through turbine blades to generate
  electricity. About 3 of our total energy in the
  United States comes from waterpower. Small
  generators are being developed to generate
  electricity from small streams and rivers.

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RENEWABLE RESOURCES

• OCEAN POWER
• Experiments are currently under way to capture
  power from the tides. Other efforts are being
  directed toward using temperature changes and
  wave action to produce electricity. There may be
  enough energy in the oceans to power all the
  Industrial machines in the world. But we still
  need to discover some practical ways to harness
  this power.

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RENEWABLE RESOURCES

• SOLAR POWER
• The sun's energy can be used to directly heat
  buildings or to provide hot water. It can also be
  converted to electricity. Photovoltaic devices
  (often called "solar cells") are expensive and
  can as yet produce only small amounts of
  electricity. Although solar power presently
  provides less than 1 of our energy, future
  developments may make it a convenient and
  inexpensive source of energy.

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RENEWABLE RESOURCES

• WIND POWER
• Windmills have been used for many years to pump
  water or to grind flour. Modern wind devices are
  being developed to generate electricity. Small
  wind turbines can light a home or run small
  appliances. Less than 1 of our energy is now
  being produced by wind power, but larger, more
  efficient generators are being tested.

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Forms of Energy

• All forms of energy are related.
• Each form can be converted into any other form.
• Remember, you can not create or destroy energy,
  only change its form.

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Potential Energy

• Defined as energy that is stored in an object due
  to its position, shape, or other feature.

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Kinetic Energy

• Defined as energy in motion.

• A generates 1,210,000 ft-lbs of energy!
• B generates only 4,840 ft-lbs of energy.