What is their common relationship to energy?
(Revised 2001 edition)
What is their common relationship to energy?
(Revised 2001 edition)
1. At the left, click on the Energy Source Icon of your choice.
2. A brief description of the energy source will appear in this panel.
3. Numbered buttons below the description will take you to a web site.
4.The web site may provide additional sites for information.
5.To return, click on any Energy Source Icon on the left, or click on the browser return.
Coal is a rock that burns as it releases energy. It is mostly made of the chemical element carbon. Some coal is brown and crumbly, and some coal is hard, black, and glossy. The greater the percentage of the coal that is carbon, the higher its rank or potential energy. Coal is among the fossil fuels along with oil (petroleum), and natural gas. The fossil fuels are considered non-renewable energy resources.
Natural Gas as we know it is made up mostly of methane. Methane, a combination of hydrogen and carbon, is formed when plants and animals (organic matter) are trapped beneath the sedimentary layers of the earth. Millions of years ago these organisms died and were buried along with mud and sand, usually on the floors of lakes, oceans and river beds. The organic matter was slowly broken down by bacteria.
This process consumed most of the oxygen, nitrogen, phosphorus, and sulfur and left behind deposits high in hydrogen and carbon. As the layers of sediment increased, so did the pressure and temperature, creating fossil fuels. Higher temperatures produced lighter petroleum, while lower temperatures produced thicker asphalt-type materials. Eventually the petroleum migrated, or moved out of the source rock and into reservoir rocks where man could extract the fuel for processing and use.
Petroleum (oil) is a member of the fossil fuels, which include, coal, oil, and natural gas. These were all formed from the decay of plants and animals that lived millions of years ago. These organisms died and were buried along with mud and sand, usually on the floors of lakes, oceans and river beds. The organic matter was slowly broken down by bacteria.
This process consumed most of the oxygen, nitrogen, phosphorus, and sulfur and left behind deposits high in hydrogen and carbon. As the layers of sediment increased, so did the pressure and temperature, creating fossil fuels. Higher temperatures produced lighter petroleum, while lower temperatures produced thicker asphalt-type materials. Eventually the petroleum migrated, or moved out of the source rock and into reservoir rocks where man could extract the fuel for processing and use.
Wind power is a renewable resource. Wind is a form of solar energy. About 2% of the solar radiation that falls on the earth is converted to wind energy in the atmosphere. At any given moment, half of the earth's atmosphere is exposed to the sun, and an equal amount is in shadow. The cyclical heating and cooling transforms the biosphere into a huge heat engine, generating energy, some of which is manifested as wind.
Like solar energy, the major drawback to the use of wind as an important energy source is the problem of storage. Wind can be used to generate electricity, but only if the winds constantly remain over 8-10 mph. Thus, effective storage mechanisms, such as batteries, must be used if wind is to be a substitute for current sources of energy.
Mankind has been making use of wind power for centuries. One of the first known uses was to propel sailing ships. This was followed, centuries later, by the development of windmills. Windmills enabled the Netherlands to become one of the world's most industrialized nations by the 17th century. In the United States, windmills played an increasingly important role in the nations development from the early 1800's through the first quarter of the twentieth century.
Geothermal Energy can be harnessed from the Earth's natural heat associated with active volcanoes or geologically young inactive volcanoes still giving off heat at depth. Steam from high-temperature geothermal fluids can be used to drive turbines and generate electrical power, while lower temperature fluids provide hot water for space-heating purpose, heat for greenhouses and industrial uses, and hot or warm springs at resort spas. For example, geothermal heat warms more than 70 percent of the homes in Iceland, and The Geysers geothermal field near Santa Rosa, in Northern California produces enough electricity to meet the power demands of San Francisco.
The Earth's crust, on which we live and depend, is in large part the product of millions of once-active volcanoes and tremendous volumes of magma that did not erupt but instead cooled below the surface.
Solar Energy, provided by the sun is the most inexhaustible and cleanest source of energy known. Its heat and light arrive week in and week out - free. But not in uniform amounts each day, or in concentrated form, and not at all at night. Consequently, the barriers to greater use of solar energy by a world faced with dwindling energy resources are significant: mainly, diffusion and the inability economically to store solar energy, use it directly, or convert it to electricity.
Hydropower produces about 20% of the world's electricity. In the United States, this resource accounts for 12% of the nation's supply of electricity. This 12% can be thought of in the following ways: (1) Hydropower produces more than 90,000 megawatts of electricity annually, which is enough to meet the needs of 28.3 million consumers. (2) Hydropower accounts for over 90% of all electricity that comes from renewable resources (e.g.- solar, geothermal, wind, biomass). (3) Hydropower is generated at only 3% of the nations 80,000 dams.
The process starts with the annual hydrologic, or water cycle, providing seasonal rain and runoff from snowpack. The runoff from rain and snow collects in lakes, streams and rivers and flows to dams downstream. The water funnels through a dam, into a powerhouse and turns a large wheel called a turbine. The turbine turns a shaft that rotates a series of magnets past copper coils in a generator to create electricity. The water then returns to the river. From the powerhouse, transmission lines carry electricity to communities.
The principle of producing electricity by heat is the same in nuclear power production as in coal or oil based energy production. By heat, the water is boiled to high pressure steam. The steam rotates the turbine. The generator attached to the turbine generates electricity. In a nuclear power plant the heat needed for producing electricity is generated in a nuclear reactor by the fission of atomic nuclei.
In the energy production, nuclear energy replaces fossil fuels, mainly coal, which pose significant environmental hazards. Of the new energy forms, nuclear power is so far the only one ready for large-scale energy production. In addition, nuclear power is economical and the annual fuel reserve of a nuclear power plant can be transported in just a few truck loads.
Biomass describes all solid material of animal or vegetable origin from which energy may be extracted. Plant products (such as corn husks, branches, or peanut shells), waste paper, and cow dung are examples of biomass fuels. Biomass can be heated, burned, fermented, or treated chemically to release energy.
Since all biomass is produced by photosynthesis, basic research in photosynthesis may provide systems that directly convert sunlight into fuels. Although biomass already has many uses - from direct burning of wood and wood residues to converting animal wastes to gas-it will play a greater role in the future as research continues and the cost of oil continues to rise.
What other sources of energy for electricity can you find that are not listed among the Energy Sources on the left?
What are renewable energy sources?
How is Hydrogen used as a source of energy for producing electricity?
How are tidal and wave motion used as a source of energy?
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