Most renewable energy sources originate from the sun (solar energy). These include bioenergy and wind energy, which ultimately derived their energy from the sun. Tidal energy originates from the gravitational pull of the moon, and geothermal energy results from hear trapped below the surface of our planet,

All of these renewable resources hold out a great promise for the future. At present, they are more expensive than fossil fuels but their sustainability but their lesser environmental impacts make them attractive alternatives to fossil fuels. None are without problem however and we will now examine the pros and cons of the two most significant sources of renewable energy – Solar and wind

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