Energy is the quantitative property that must be transferred to an object in order to perform work on, or to heat, the object. Energy is a conserved quantity; the law of conservation of energy states that energy can be converted in form, but not created or destroyed.
3. Energy
• Energy is “the ability to do work” on an object
• Heat (thermal)
• Light (radiant)
• Motion (kinetic)
• Electrical
• Chemical
• Nuclear energy
• Gravitational
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4. Energy
• Two Primary Types of Energy
• Potential Energy – stored energy
• Kinetic Energy – motion energy
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5. Energy
• Two Primary Types of Energy
• Potential Energy – stored energy
• Kinetic Energy – motion energy
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6. 1st Law of Thermodynamics
• Law of Conservation of Energy
• Energy can be transformed from one form to
another, but can be neither created nor destroyed
• When energy passes, as work, as heat, or with
matter, into or out from a system, the
system's internal energy changes in accord with the
law of conservation of energy.
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7. 1st Law of Thermodynamics
• Equivalently, perpetual motion machines (machines
that produce work without the input of energy) are
impossible.
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8. Energy Generation
At the center of nearly all power stations is a generator, a
rotating machine that converts mechanical power (primary)
into electrical power (secondary) by creating relative motion
between a magnetic field and a conductor.
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9. Energy Consumption
• Electricity is an essential part of modern life and important
to the U.S. economy.
(Lighting, heating, cooling, refrigeration, appliances,
computers, electronics, machinery, and public
transportation systems.)
• U.S. retail sales of electricity by sectors in 2016:
• Residential–38%
• Commercial–37%
• Industrial–25%
• Transportation–0.2% (mostly by public transit systems)
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10. Energy Consumption
Cooling is the single largest use of electricity by the U.S. residential
sector
1. Space Cooling (air conditioning)
2. Water Heating
3. Lighting
4. Space Heating
5. Refrigeration
6. Televisions
Clothes washers and dryers, computers, dishwashers, small appliances,
and other electrical equipment was about 40% of total U.S. residential
sector electricity use in 2016.
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12. Energy Consumption
• Top 10 Countries by Electricity Use
• Electricity consumption in the United States was
about 3.85 trillion kilowatthours (kWh) in 2016
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20. Nonrenewable Energy
• Fossil Fuel - a natural fuel such as coal or gas,
formed in the geological past from the remains of
living organisms
• Coal
• Oil
• Natural Gas
• Nuclear
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21. Nonrenewable Energy
• Coal is a combustible black sedimentary rock
composed primarily of carbon.
• the largest source of energy for the generation of
electricity worldwide
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