Renewable energy : Alternative of Fossils fuel

Now that oil prices are getting more and more expensive different countries are focusing on Renewable energy as an alternative energy source. Many countries now are depending on non-renewable energy source like; coal, oil and natural gas to supply most of their energy needs, but reliance on this non-renewable energy or fossil fuels presents a big problem. World supply of fossil fuels is limited and after some years supply of fossils fuel will get stop. In that case we will have to start to find other source of energy that is renewable source of energy. Although renewable cannot yet replace all existing energy sources, they can supplement power generated by utilities and increase the diversity of our energy supply.
The rapidly increasing industrialization in developing countries puts a strain on already limited resources and adds to the continuing deterioration of the global environment. Finding alternative sources of energy is crucial. Renewable energy initiatives will result in reduced demand for fossil-fuelled electricity generation, thereby reducing greenhouse gas emissions.

A significant advantage of the use of renewable energy systems is that they are environmentally friendly because overall they result in lower dangerous pollutant emissions, this and one other major factor, they are essentially inexhaustible.

Renewable energy effectively uses natural resources such as sunlight, wind, rain, tides and geothermal heat, which may be naturally replenished
Renewable energy technologies range from solar power, wind power, hydroelectricity/micro hydro, biomass and biofuels for transportation.

Some of them are:
Solar energy : "solar energy" refers to energy that is collected from sunlight. Solar energy can be applied in many ways,
including to:
Generate electricity using photovoltaic solar cells.
Generate electricity using concentrated solar power.
Generate electricity by heating trapped air which rotates turbines in a Solar updraft tower.
Heat buildings, directly, through passive solar building design.
Heat foodstuffs, through solar ovens.
Heat water or air for domestic hot water and space heating needs using solar-thermal panels.
Heat and cool air through use of solar chimneys.
Generate electricity in geosynchronous orbit using solar power satellites.
Solar air conditioning

Wind power: Airflows can be used to run wind turbines. Modern wind turbines range from around 600kW to up to 5 MW of rated power, although turbines, with rated output of 1.5–3 MW, have become the most common for commercial use. Wind power is growing at the rate of 30% p.a. has a worldwide installed capacity of over 100 GW and is widely used in several European countries and the USA

Water power : Energy in water (in the form of motive energy or temperature differences) can be harnessed and used. Since water is about 800 times denser than air, even a slow flowing stream of water, or moderate sea swell, can yield considerable amounts of energy.

Liquid biofuel : Liquid biofuel is usually either a bioalcohol such as ethanol fuel or a bio-oil such as biodiesel and straight vegetable oil. A major benefit of biodiesel is lower emissions. The use of biodiesel reduces emission of carbon monoxide and other hydrocarbons by 20 to 40%. Brazil has one of the largest renewable energy programs in the world, involving production of ethanol fuel from sugar cane, and ethanol now provides 18 percent of the country's automotive fuel. As a partial result, Brazil, which years ago had to import a large share of the petroleum needed for domestic consumption, recently reached complete self-sufficiency in oil.

Benefits of Renewable Energy
have minimal or no negative environmental or social impact;
not deplete natural resources;
meet the needs of people today and in the future in an accessible, equitable and efficient manner;
protect air, land and water;
have little or no net carbon or other greenhouse gas emissions;
be safe today and not burden future generations with unnecessary risk.

It is clear that to save earth environment from pollution and from Global Warming, everyone will have to come forward and increase awareness about renewable source of energy. Especially Government of developed countries should increase research to bring more method to convert renewable source into cheap form of energy.
“SAVE EARTH”
Article Source : wikipedia