Sources of energy x 'a'

Science Project

Sources of Energy

A good source of energy would be one:• Which would do a large amount

of work per unit volume or mass.• Be easily accessible.• Be easy to store and transport.• Be economical.• Which does not pollute.

Fossil Fuels• Fossil fuels, energy-rich substances

that have formed from long-buried plants and microorganisms.

• Fossil fuels, which include petroleum, coal, and natural gas, provide most of the energy that powers modern industrial society.

• The gasoline that fuels our cars, the coal that powers many electrical plants, and the natural gas that heats our homes are all fossil fuels.

Disadvantages Of Fossil Fuel

• Acid rain and global warming are two of the most serious environmental issues related to large-scale fossil fuel combustion.

• Other environmental problems, such as land reclamation and oil spills, are also associated with the mining and transporting of fossil fuels.

• When fossil fuels are burned, sulfur, nitrogen, and carbon combine with oxygen to form compounds known as oxides.

• When these oxides are released into the air, they react chemically with atmospheric water vapor, forming sulfuric acid, nitric acid, and carbonic acid, respectively.

• These acid-containing water vapors—commonly known as acid rain—enter the water cycle and can subsequently harm the biological quality of forests, soils, lakes, and streams.

• Combustion of fossil fuels produces unburned fuel particles, known as ash.

• In the past, coal-fired power plants have emitted large amounts of ash into the atmosphere.

• However, government regulations also require that emissions containing ash be scrubbed or that particles otherwise be trapped to reduce this source of air pollution.

• While petroleum and natural gas generate less ash than coal, air pollution from fuel ash produced by automobiles may be a problem in cities where diesel and gasoline vehicles are concentrated.

Thermal Power Plant• In a thermal power plant, steam is

produced and used to spin a turbine that operates a generator.

• Shown here is a diagram of a conventional thermal power plant, which uses coal, oil, or natural gas as fuel to boil water to produce the steam.

• The electricity generated at the plant is sent to consumers through high-voltage power lines.

Bio Fuel•

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Hydro Power Plant

Wind Energy• Wind Energy, energy contained in

the force of the winds blowing across the earth’s surface.

• When harnessed, wind energy can be converted into mechanical energy for performing work such as pumping water, grinding grain, and milling lumber.

• By connecting a spinning rotor to an electric generator, modern wind turbines convert wind energy, which turns the rotor, into electrical energy.

Solar Energy• Solar Energy, radiation produced by

nuclear fusion reactions deep in the Sun’s core.

• The Sun provides almost all the heat and light Earth receives and therefore sustains every living being.

• The total radiation power (1.4 kilowatts per square meter, called the solar constant) varies only slightly, about 0.2 percent every 30 years.

Tidal Energy•

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Wave Energy• Energy produced for domestic or

industrial use by harnessing and converting the energy of sea waves is called wave energy.

• Wave energy would be a viable proposition only where waves are strong.

• A wide variety of devices have been developed to trap wave energy for rotation of turbine and production of electricity.

Ocean Thermal Energy• The water at the of the sea or ocean

is heated by the sun while the water in deeper sections is relatively cold.

• This difference in temperature is exploited to obtain energy in ocean-thermal-energy conversion plants.

• These plants can operate if the temperature difference between the water at the surface and water at depths up to 2 km is 293 k or more.

Environmental Consequences

• Exploiting any source of energy disturbs the environment in some way or the other.

• The source we choose depends on factors such as the ease of extracting energy from that source, the economics of extracting energy from the source, the efficiency of the technology available and the environmental damage that will be caused by using that resource.