Renewable Energy - Overview
The energy from the sun, and it's indirect manifestations, such as winds, waves and biomass growth, can be tapped to power machines to generate electricity.
So can the moon's gravitational pull in the tides, and water flows in rivers and streams created by the hydrological cycle.
Solar energy can be used directly for heating or it can be converted to electricity in a photovoltaic cell.
Energy converted from sunlight via photosynthesis creates vegetation. Biomass is an abundant source of energy, and we can design more productive energy crops to increase its abundance.
Wind power can be harnessed by modern wind turbines which extract the energy from the wind to produce electricity.
Water power can be harnessed to generate electricity.Hydro-electric power makes use of a reservoir of water as a store of power.
Tidal and wave power collect power from the fast moving flows of water using turbine like technology.
With wind, tidal flow and wave power, we are infact copying nature, and its habit of relying on time to collect energy. The winds involve large masses of moving air built up over time and covering vast areas. Renewable energy machines simply tap into this flow.
The potential energy of water in reservoirs behind dams feeds hydro-electric plants. Around 20% of the world's electricity already comes from this source.
Geology plays a key role in relation to geothermal energy - an energy source that already provides a substantial amount of power around the world.
If you draw a graph showing the growth of all energy technologies over the past decade one curve will be completely off your scale.
Wind power is the fastest growing energy technology in the world. Starting from nothing 10 years ago, there is now 20,000 megawatts generating capacity in operation around the world.
That's the equivalent of about ten nuclear power stations. |
