5.5 Renewable and Non-Renewable Sources
The resources of energy which are replaced by new ones after their use are called renewable energy sources. On the other hand, non-renewable sources are those which are depleted with continuous use. Once they run out, they are not easily replaced by new ones.
Sources such as hydroelectricity, solar energy, wind energy, tidal energy, wave energy, and geothermal energy are renewable. These are replaced by new ones. For example, snowfall and rainfall are continuous processes. Therefore, the water supply to the reservoirs of dams for generation of hydroelectric power will never end. Likewise, solar energy will remain available forever. The same is the case with wind and tidal energy.
Non-renewable sources include fossil fuels and nuclear energy. The remnants of plants and animals buried under the Earth took millions of years to change into fossil fuels. These fuels are in limited quantity. Once they are used up, it will take further millions of years to form new ones. Similarly, fuels for nuclear energy are also limited.
As the need for energy is increasing day by day, there is a need to develop other non-traditional renewable energy sources.