Non-conventional sources of energy are those sources that are not in common use at this time but are being considered or explored to bring to routinely used in the future. With the exhaustion of conventional sources of energy, the search for non-conventional sources of energy has intensified.
- Conventional sources of energy are coal, gas, oil, wood, and electricity. These sources are in routine use nowadays.
- Non-conventional sources of energy are solar energy, geothermal energy, wind energy, tidal power, and ocean thermal gradients.
The energy of the sun is called solar energy. It has been estimated that on average 180,000 kilowatts of solar energy are falling per square kilometer of the earth. Solar energy is utilized in two ways. A solar furnace contains thousands of mirrors to focus the sun’s rays.
In this way, solar heaters produce heat used in industry or houses. The heaters heat up water or air. Solar energy can also be used indirectly. Solar cells made up of panels of semiconductors (usual silicon) are used which when illuminated by sun-generated electricity. This kind of cell has frequently been used in space probes. They have not become popular in domestic use due to high cost.
Windmills can be used for the generation of electricity. Previously windmills were used for grinding grains. The rotating wings of the windmills can be attached to a magnet which gives an electric current with the rotation. Low power, high cost, and uncertainties of weather had not made power generation through the wind popular.
Geothermal energy is the heat energy production inside the earth usually due to radioactivity. Geothermal electricity plant changes the geothermal energy into electricity. Hot water from springs is being used for power generation, particularly in the USA, hot springs, however, are used as geysers for heating houses.