Conventional : Energy that has been used from ancient times is known as conventional energy. Coal, natural gas, oil, and firewood are examples of conventional energy sources. (or usual) sources of energy (electricity) are coal, oil, wood, peat, uranium.

Non-conventional (or unusual) sources of energy include:
• Solar power
• Hydro-electric power (dams in rivers)
• Wind power
• Tidal power
• Ocean wave power
• Geothermal power (heat from deep under the ground)
• Ocean thermal power (the difference in heat between shallow and deep water)
• Biomass (burning of vegetation to stop it producing methane)
• Biofuel (producing ethanol (petroleum) from plants

We hope that all the conventional sources will become rare, endangered and extinct, as they produce lots of carbon dioxide that adds to the greenhouse effect in the atmosphere (uranium leaves different dangerous byproducts).

And we similarly hope that all the non-conventional sources will become conventional, common, and every day, as they are all free, green and emit no carbon dioxide (well, biomass does, but it prevents the production of methane which is a greenhouse gas 21 times more dangerous that CO2).

Brief description of non-conventional energy resources:

Solar Energy:

Most of the renewable energy is ultimately “Solar energy” that is directly collected from sun light. Energy is released by the Sun as electromagnetic waves. The energy reaching earth’s atmosphere consists of about
• 8% UV radiation
• 46% visible light
• 46% infrared radiations

Wind Energy:

The origin for Wind Energy is Sun. When sun ray falls on the earth, it’s surface gets heated up and as a consequence unevenly winds are formed. Kinetic energy in the wind can be used to run wind turbines but the output power depends upon the wind speed. Turbines generally require a wind in the range of 20km/hr. In practice relatively few land areas have significantly prevailing winds. Otherwise wind power is one of the most cost competitive renewable energy today and this has been the most rapidly-growing means of electricity generation at the turn of 21st century and provides a complement to a large scale base load power stations. Its long term technical potential is believed to be 5 times current global energy consumption or 40 times current electricity demand.

Water Power

Energy in the water can be harnessed and used in the form of motive energy or temperature difference. Since water is about 1000 times heavier than air, even a slow flowing stream of water can yield great amount of energy.

There are many forms:
• Hydroelectric energy, a term usually reserved for hydroelectric dam
• Tidal power, which captures energy from the tides in horizontal direction. Tides come in, raise water levels  in a basin, and tides roll out. The water is made to pass through turbine to get out of the basin. Power generation through this method has a varying degree of success.
• Wave power, which uses energy in waves. The waves will usually make large pontoons go up and down in the water. The wave power is also hard to tap.

Hydro electrical energy is therefore  only viable option. However , even probably this option is also not there with the developed nations for future energy production because most major sites within these nations with potential for harnessing