Energias Renovables

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Renewable energy
Renewable energy is energy which comes from natural resources such as sunlight, wind, rain, tides, and geothermal heat, which arerenewable (naturally replenished). About 16% of global final energy consumption comes from renewables, with 10% coming from traditional biomass, which is mainly used for heating, and 3.4%from hydroelectricity.
New renewables are growing very rapidly.
Climate change concerns, coupled with high oil prices, peak oil, and increasing government support, are driving increasing renewable energylegislation, incentives and commercialization.
According to a 2011 projection by the International Energy Agency, solar power generators may produce most of the world’s electricity within 50 years,dramatically reducing the emissions of greenhouse gases that harm the environment.

Renewable energy involve natural phenomena such as sunlight, wind, tides, plant growth, and geothermal heat.
Renewableenergy is derived from natural processes that are replenished constantly. In its various forms, it derives directly from the sun, or from heat generated in the deep of the earth.
Electricity and heatgenerated from solar, wind, ocean, hydropower, biomass, geothermal resources, biofuels and hydrogen derived from renewable resources are also part of the Renewable energy.
Renewable energy replacesconventional fuels in areas such as: power generation and hot water:
* Power generation: Renewable energy provides 18 percent of total electricity generation worldwide.
* Heating: Solar hotwater makes an important contribution to renewable heat in many countries, most notably in China.

Wind power
Airflows can be used to run wind turbines. The power output of a turbine is a functionof the cube of the wind speed, so as wind speed increases, power output increases dramatically. 

Hydropower
Energy in water can be controlled and used. Since water is about 800 times denser...