Alternitive energy

A natural resource qualities asa renewable resource if it is replenished by natural processes at a rate comparable or faster than its rate of consumption by human or other users. solar radiation, tides, winds, and hydroelectricity are perpetual resources that are in no danger of being in excess of their long- term availability. Term also has the connotation of sustainability of the handling of waste products by the natural environment.

Some natural renewable resources such as geothermal, fresh water, timber, and biomass must be carefully managed to avoid exceeding the environment's capacity to replenish them. A life cycle assessment provides a systematic means of evaluating renewability .

Gasoline, coal, natural gas, diesel, and other commodities deprived from fossil fuels are non-renewable. Unlike fossil fuels, a renewable resource can have a sustainable yield.

Wind power

1. What is the science behind this type of energy? How does it work?

Wind power is derived from uneven heating of the Earth's surface from the sun and the warm core. Most modern wind power is generated in form of electricity by converting the rotation of turbine blades into electrical current by means of an electrical generator.

In windmills ( a much older technology ) wind energy is used to turn mechanical machinery to do physical work, Like crushing grains or pumping water.

2. How has this type of energy been used elsewhere in the United States and/or around the world?

Wind power in Australia is clean and renewable and a typical wind turbine can meet the energy needs of up to 1000 homes. The technology is proven, fast to build and economical compared with other renewable energy technologies. There were 42 wind farms operating in Australia as at February 2007.

Australia is the highest emitter of greenhouse gases per capita in the developed world and wind power is well placed to grow and deliver greenhouse gas emission cuts on a cost competitive basis. A typical 50 megawatt wind farm in Australia can reduce greenhouse gas emissions by between 65,000 and 115,000 tonnes a year.

3. How much would it cost to provide this type of energy? What would the cost be to consumers?

Wind energy is one of the cheapest of the renewable energy technologies. It is competitive with new clean coal fired power stations and cheaper than new nuclear power. The cost of wind energy varies according to many factors. An average for a new onshore wind farm in a good location is 3-4 pence per unit, competitive with new coal (2.5-4.5p) and cheaper than new nuclear (4-7p). Electricity from smaller wind farms can be more expensive.

Now , states of the art wind power plants at excellent sites are generating electricity at less than 5 cents/kWh. Costs are contributing to decline as more and larger plants are built and advanced technology is introduced.

4. What are the potential positive or negative effects on the environment?

greater fuel diversity and less dependence on fossil fuels , which are often subject to rapid price fluctuations and supply problems. This is significant issue around the world today ,with many countries rushing to install gas -fired electric generating capacity because of its low capital cost . As world gas demands increases , the prospect of supply interruptions and fluctuations will grow, making further alliance it unwise and increasing the value of diversity .

Long term income to ranchers and farmers who own the land on which windfarms are built.

Geothermal Energy

1. What is the science behind this type of energy? How does it work?

The word Geothermal comes from the greek words geo (earth) and therme (heat), and mean the heat of the earth. Geothermal power directly harnesses the natural flow of heat from the ground . The available energy from natural decay of radioactive elements in the earth's crust and mantle is approximately equal to that of incoming solar energy. In Geothermal power plants, We use the natural hot water and stem from the earths to turn turbine generators to produce electricity. Unlike fossil fuels power plants, no fuel is burned,. Geothermal power plants give off water vapor, But have no smokey emissions.

The electricity energy generated i the u.s. from geothermal resources is more than twice that solar and wind combined.

2. How has this type of energy been used elsewhere in the United States and/or around the world?

3. How much would it cost to provide this type of energy? What would the cost be to consumers?

4. What are the potential positive or negative effects on the environment?