| Fossil fuels such as oil, natural gas, and coal are used | | | | Biomass energy comes from wood, garbage, food |
| around the world as primary sources of energy. | | | | crops, manure, grasses and plants, agricultural and |
| Because they are being used up much faster than | | | | forestry waste and residue. It basically comes from |
| they can be renewed, they are known as | | | | refuse. This renewable energy is also not new. It was |
| nonrenewable sources. | | | | used over 100 years ago in the form of wood |
| Nonrenewable energy sources represent about 90% | | | | burning, which supplied 90% of energy needs at that |
| of the energy used today. These sources are being | | | | time. When biomass is burned, it produces heat or |
| depleted. Since they are known to have an effect on | | | | electricity. It can also be converted to methane gas, |
| air quality, causing human and environmental health | | | | which is the main ingredient of natural gas. It |
| problems, a greater emphasis is being placed on | | | | represents 3% of the energy in the United States. |
| renewable energy sources as the new frontier for | | | | Although biomass can pollute the air and releases a |
| energy. Renewable energy sources consist of solar, | | | | greenhouse gas, it is not as pollutant as fossil fuels. |
| hydro, biomass, geothermal and ocean. These | | | | Geothermal energy is basically the Earth's heat. It is |
| sources of energy will never become exhausted and | | | | drawn from hot dry rocks, magma, hot water springs |
| are environmentally friendly, since they do not | | | | and hot geysers. These are found inside the Earth's |
| contribute to greenhouse effects or global warming. | | | | underground. Some are found deep in the earth's |
| Solar energy is the most readily available renewable | | | | surface and others are found closer to the surface. |
| energy source. We have used the sun's energy for | | | | Today, this type of energy is used to heat water in |
| billions of years. Prehistoric men magnified its strength | | | | swimming pools and spas, as well as, to warm |
| to start fires. Today, solar panels absorb energy | | | | buildings like greenhouses. It can also be used to |
| from the sun to produce heat for cooking and | | | | produce electricity through the use of a geothermal |
| heating, as well as, for electrical needs. This heat | | | | power plant. In these plants the hot water travels |
| absorption is stored for later use and is an indirect | | | | through turbines, which are connected to a |
| conversion of energy. Currently, electric companies | | | | generator. |
| are trying to use photovoltaic technologies to | | | | Ocean Energy is obtained from ocean waves or |
| convert solar energy directly to electricity. | | | | temperature differences in water. Wave energy is |
| Hydro energy draws on energy produced by flowing | | | | the kinetic energy from the movement of water. |
| water. Waves are the result of wind interacting with | | | | Tidal energy entails trapping tidal waves in reservoirs |
| the surface of the sea. This interaction produces a | | | | behind dams. Ocean Thermal Energy Conversion uses |
| transfer of energy that can be extracted for power | | | | the differences in water temperatures from the |
| generation using turbine generators. Although | | | | surface water to deeper down depths of water as |
| hydropower is non-polluting, it can do environmental | | | | an energy source. In order for this to work there |
| harm. Hydroelectric generating stations can change | | | | must be a temperature difference of 38 degrees |
| the flow of the sea and in doing so harm plants and | | | | Fahrenheit. |
| animals. | | | | As you can see, there are various renewable energy |
| Wind energy, or kinetic energy, is drawn from the | | | | sources available to us as an alternative to fossil |
| movement of air. It has been used for hundreds of | | | | fuels. There are many advantages to them among |
| years for sailing, grinding grain and irrigation. Today, | | | | the most popular being that they will not deplete in |
| wind turbines transform energy from wind to | | | | supply, meaning they will be around forever. |
| mechanical energy or to charge batteries. The wind | | | | Renewable energy sources are not new. They have |
| machines, or wind turbines collect the kinetic energy | | | | been utilized in some way for many years. |
| by capturing the wind in its blades. The blades then | | | | Unfortunately, low fossil fuel prices have stunted |
| turn an electric generator to produce energy. | | | | renewable energy's popularity and growth in the |
| Unfortunately, wind energy collection is unavailable on | | | | United States. But an increasing awareness of human |
| windless days. Even though it is a clean form of | | | | and environmental concerns, as well as, a need to |
| energy it has had a negative effect on the wild bird | | | | find non-exhaustible energy sources, will keep it as a |
| population and some consider the giant wind turbine | | | | mainstay for the future. |
| machines not attractive looking. | | | | |