Alternative Energy Sources

Alternative Energy Sources

Mankind needs an energy source to live. This can be wood, coal, and petroleum. The need for energy also brings its problems like pollution. But the main problem is that its limited resource. Nothing is infinitive so this brings the so-called energy problem. Strictly speaking, no energy problem exists, but as the modern society grows the need for energy also grows. Therefor scientists try to find new resources of energy. But first lets see how they separate energy resources.
Scientists separate energy resource into two groups:
1. Renewable Resources.
2. Nonrenewable Resources.
Renewable Resources
Renewable resources are the ones that replenish themselves naturally in a relatively short time and will therefor always be available. Geothermal energy, hydroelectric power, peat, ocean thermal energy, solar energy, tidal energy, wind power, and fuel wood are renewable resources but they also are limited to their usage for example geothermal can be limited if not used properly. We will get more into it below. These are also alternative resources of energy.
Geothermal Energy
Geothermal energy is the heat below the ground level. This can change from hot water to hot rocks. This system is being used recently. Geothermal energy can be used for heating use and power generation.
Heating Use
Geothermal fluids may be used directly in houses, greenhouses or in the industry if the heat is close to population. This use is not used in many countries. However, 65% of Iceland's homes and greenhouses use this method of heating like The United States, Denmark, and Sweden.
Industrial use of this method is limited to industries needing less than 200° Celsius.
Power Generation
Geothermal fluids are most used for power generation. Italy has been using geothermal steam from 1904 to produce power. China, Indonesia, Japan, Kenya, Mexico, New Zealand, the Philippines and the Soviet Union use this system of power generation. The largest plant is in the United States near San Francisco, California. The present power generation capacity is 2000 megawatts. This place is the only place in the United States known to generate electricity. Other resources are not enough for power generation. It is been used since 1960.
The water for power generation mustn't be lower than 200°Celcius
Hot, Dry Rocks
This is new technique it uses hot rocks. By injecting cool water through deep wells the water heats. This method is used only near Los Alamos, New Mexico, four deep wells, comprising two closed loops, have been drilled into solid rock on the rim of a dormant volcano. Well depth about 4 km, the heat of the rocks at this depth reaches about 240°Celcius. Cold water is forced into two of the wells under very high pressure, opening minute fractures and creating a network of cracks that multiplies the hot surface area and acts as a heat reservoir. The pressurized water-now heated to 190°Celcius-shoots up the remaining two wells to the surface where, in a heat exchange, it vaporizes a secondary liquid. The process has been used to power electric generators at the site.
Hydroelectric Power
Hydroelectric power is the largest energy source in our planet after wood. It is falling waters energy.
Development
The earliest reference of energy gained from falling water is a Greek poem talking about falling water dating back to 4th century BC. The Romans used the Waterwheel but the waterwheel also meant less need of manpower that brought unemployment so the development paused until the wars the need grew because of low population. By the 1800, thousands were built in Europe and England.
Waterpower was first used to produce electricity on Fox River, near Appleton, Wisconsin US. On September 30,1882. After this time hydroelectric power grew. By the early 1990s, it accounted for 25% of global electricity and 5% of total world energy use.
Today total world hydroelectric power production amount is approximately 2044 billion kilowatts per hour, generated at dams with total capacity of 549000 megawatts. In order Canada, United States, Brazil are the best producers of electricity. Turkey also is good in hydroelectric power. Its Güneydoğu Anadolu Project is one of the world largest dams.
Effects
Hydroelectric power is economic and is a powerful source of electricity however the environmental effects of it are sometimes bad because farming land and houses are left under the water after building so it causes some environmental damage.
New Ways of Hydroelectric Power
A group of scientists designed a turbine that would get set on the floor of moving water like a stream. These turbines would generate electricity. They will be tested on the Gulf Stream. The propellers would be based on high efficiency submarine propellers.
Peat
Peat is a natural deposit of old plants and animals. In Europe, peat is used as an energy resource but in the United States, peat is used as fertilizers. Peat is the starting of a coal bed.
Ocean Thermal Energy
Ocean thermal energy is a method of energy production. The first plant was built in 1929 by a French engineer on the coast of Cuba. The plant utilizes temperature differences between warm surface water and colder water at depths of approximately 1000 m.
The plant takes hot water located at the upper layer of the ocean into an evaporator where, because of a low pressure, some of this water is flashed into low-pressure steam, which gets used in a steam turbine. The exhaust steam passed into a condenser, which is maintained at still lower pressure and it, is condensed by cold water brought up from the ocean depths. There were some problems of course the pipe that brought cold water from deep sea used to break in storms, this caused the plant to shut down.
Solar Energy
Solar energy is a term that holds a wide range of sources so we will separate them.
Power Generation
Direct Usage of the Light
Electricity can be gained by solar cells, which collect light energy. When light hit the solar cell, light releases electrons. Not much electricity is gained with commercial cells only about 15% of the light hitting the surface can be transformed into electricity. However, new experimental cells can convert up to 30% of the light hitting the surface of the cell. Solar cells were developed by Bell Laboratories in the 1950s. Solar cells are all parts of our lives. They are used from watches to space satellites.
Indirect usage of the Light
The solar energy can be used to heat water and send the steam through turbines to generate electricity.
Heating Use
Solar energy is used to heat water and air. This way is used in many places:
Residential Use
Solar energy is used to heat water inside housing for home use.
Industrial Use
Solar energy in the industrial world is quite important because it is cheap to produce hot water like this but the industry is limited to jobs needing less than 315°celcieus of heat. It is also important to be in a place that has sun almost all the time in a year.
Tidal Energy
Tidal energy can be gained by building a dam on a shore. The dam would be just like a dam for hydroelectricity. The doors of the dam would be opened at a tide to let the water in and while the tide goes down the water would be left from the turbines making electricity.
The biggest tidal dam is in France; it is a 240megawatt plant. Tidal plants do not generate a lot of electricity because they are only able to work at night just for three or four hours.
Wind Power
Wind power was first used by Persians in about 5th AD for irrigation. By the 12th century windmills were spread through Europe They were used to grind corn or pump water. Dutch people used windmills to pump out water after the dikes this is why the windmill is the symbol of the Netherlands.
Today wind power is mostly used for generating electricity. Todays' machines have two wings, which are connected to a generator to produce electricity.
Fuel Wood
Wood is a common fuel. It is a renewable energy source if used properly. It can replenish itself in years if used wisely.
Nonrenewable Resources
Nonrenewable resources are resources that cannot replenish themselves. Nonrenewable resources originate from two processes:
1. Photosynthesis, which happened millions of years ago, followed by the fossilization of plants and animal life.
2. The formation of Earth itself.
Fossil Fuels
These fuels originated from photosynthesis they are the bodies of animals and trees that lived before. When the bodies are left below the ground for millions of years in pressure, The bodies are fossilized and eventually form coal, oil and natural gas, which we use today.
Coal
Coal is peat after a great mass of time. Coal is formed by peat, which is buried under the ground. The heat and the pressure under the ground forms coal. Which than is mined from under the ground. Coal is used for heating and electric production. It has a big reputation but it in unfriendly to the environment.
Oil
Oil is properly the most consumed material after wood. Oil is used as a fuel and raw material for plastic and other synthetic material. This is why oil is an important material and must be consumed wisely or must have another fuel to power cars, trucks, ships and airplanes. Oil is a sophisticated material it is a mixture of gases and liquids. Oil is a fossil fuel because it is made of organic material. Oil is found under the ground or under the sea. It must be tapped by a rock.
Natural Gas
Natural gas is a flammable gas within earth's crust. This material is the second important substance after oil. Natural gas is a form of oil.
Natural gas is found in all continents except Antarctica. The biggest producers are Russia, the United States, Canada and the Netherlands.
It is mostly transported by pipes but can be transported in pressurized tanks. When gas is kept under high pressure and in low pressures it gets into a liquid form in this way it doesn’t take up much space.
It is used in houses and in the industry as a raw material and as a clean source of heat it is used to sterilize material, it is used in the glass industry and in other building material industries.

Fuels that are formed By the Formation of Earth
These fuels are nuclear fuels like uranium, plutonium, thorium, and uranium. These fuels are dangerous but are a powerful resource of energy. These fuels have a limited resource so must be used wisely. These fuels are used in some countries they are used in nuclear reactors. Most of the worlds population doesn’t want this source of energy because it is so dangerous. The danger and the effects can be seen from the Chernobyl accident happened in April 1986 causing over 100,000 to move from their houses and poisoning food and water in some European countries. Nuclear energy is also used to power ships, submarine, and space ships.
Outlook
The need for new energy sources grow as the worlds population grows this is a growing problem. Alternative energy sources are needed to overcome this problem. Fossil fuels have a limited resource and will finish.

Bibliography
"Coal and Coal Mining", Reeder, Robert T., Grolier Multimedia Encyclopedia, 1995
"Energy Source", McMullan, T. John, Grolier Multimedia Encyclopedia, 1995
"Geothermal Energy", Doolitle, J.S. Grolier Multimedia Encyclopedia, 1995
"Hydroelectric Power", Deudney, Daniel, Grolier Multimedia Encyclopedia, 1995
"Natural Gas" ,Harbaugh, John W., Grolier Multimedia Encyclopedia, 1995
"Nuclear Energy", Hansen, Kent F., Grolier Multimedia Encyclopedia, 1995
"Ocean Thermal Energy Conversion", Grolier Multimedia Encyclopedia, 1995
"Peat", Schopf, James M., Grolier Multimedia Encyclopedia, 1995
"Petroleum", Lynch, Micheal C., Grolier Multimedia Encyclopedia, 1995
"Solar Cells and Collectors", Doolittle, J.S., Grolier Multimedia Encyclopedia, 1995
"Solar Energy", Ellis, George, Grolier Multimedia Encyclopedia, 1995
"Tapping into the Gulf Stream", Popular Mechanics, February 1996.
"Tidal Energy", Hangerman, George, Grolier Multimedia Encyclopedia, 1995
"Windmills and Wind Power", Grolier Multimedia Encyclopedia, 1995,