Introduction: Energy Unit Technology Foundations Stuarts Draft High School
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.
Classifications of Energy Sources Limited Oil Coal Natural gas Uranium Unlimited Solar Wind Gravitational Tidal Geothermal Fusion Renewable Wood Biomass Gasification Biomass Fermentation Animal Power Human Muscle Power
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.
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.
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.
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.
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.
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.
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.
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.
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 &quot;solar cells&quot;) 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.
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.
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.
Potential Energy Defined as energy that is stored in an object due to its position, shape, or other feature.
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.