Hydroelectric <ul><li>People have used the power of water for many years. A large amount of the growth of the early colonial American industry is because of the use of hydropower. Since fuel such as coal and wood were not easy accessed by inland cities, American settlers had to find alternatives. Falling water was ideal for powering sawmills and grist mills. This power is captured by a dam being built to trap water, usually in a valley where there is an existing lake. Water is flows through tunnels in the dam, to turn turbine and then drives generators. The dam is much thicker at the bottom than at the top, because the pressure of the water increases with depth. </li></ul>
Fossil Fuels Fossil fuels have been a widely used source of energy ever since the Industrial Revolution which was right before the 20th century. Fossils fuels are generally easy to use to generate energy because they only require a simple direct combustion. However, a problem with fossil fuels is they have a very negative effect on the environment. Not only does their excavation from the ground significantly alter the environment, but their combustion causes a great deal of air pollution.
Fusion <ul><li>For years now people have been turning to fusion as the "energy of the future." Not only does fusion appear to be an extremely effective source of energy production, but it’s also environmentally friendly and virtually inexhaustible. Fusion as may prove to become mankind’s energy source for the 21st century and beyond. Fusion energy is the power generated by nuclear fusion reactions. In this kind of reaction, two light atomic nucleai fuse together to form a heavier nucleus and by doing this, a large amount of energy is released. </li></ul>
Solar Energy <ul><li>Solar energy is energy obtained through the use of solar panels. Although the field of research dealing with this type of solar power is relatively new, keep in mind that people have known about the energy of the sun for thousands of years. </li></ul>
Wind Power <ul><li>Mankind has made use of wind power since ancient times. Wind has powered boats and other sea craft for years. Also, the use of windmills to provide power for the agricultural tasks has added to the growth of civilization </li></ul><ul><li>. </li></ul>
Geothermal Power <ul><li>The center of the earth can reach 12000 degrees Fahrenheit. Using that heat to power things on earth would bring endless possibilities. Geothermal systems do just that. Convection (heat) currents travel quite near the surface in some parts of the world. For instance, Iceland's capital city of Reykjavik is located near hot springs that power virtually the entire city. </li></ul>
Fission <ul><li>Fission is an established method of energy production. Countries all over the world possess fission reactors capable of powering whole cities. The benefits in this type energy production are shadowed by the harm to the environment and dangerous nuclear waste by products . </li></ul>
Biomass <ul><li>Biomass is one of the oldest and most well-established energy sources in the world. Biomass is the conversion of energy that is stored in plants into energy that we can use. Biomass has many possibilities as a renewable energy source. High energy crops that can be specifically grown to be used as fuel are being developed, and scientists are starting the think about using agricultural and animal waste products as fuel sources. For example, the decomposition of organic wastes in landfill sites produces methane that can be converted into heat, electricity and possibly fuels. </li></ul>