The Power of Water
We cannot live without water and water is an inevitable part of every life on earth. We all know this, but does everyone know in how many ways we can harness energy from this wonderful resource. Some of the popular ways of powering an electric turbine using water are:
1. Ocean Thermal Energy
Ocean thermal energy conversion (OTEC) technique relies on the differential solar heating of ocean water. During the daytime, water at the surface gets heated up more than water deep down due to exposure to sun's radiations. As the famous saying goes "Nature loves symmetry," this temperature gradient helps in running liquid to power the turbine working like a heat engine.
2. Tidal Energy
Tidal energy is using the flow of the tides to fill and empty a basin at the shore. A turbine is fixed in the basin gate and hence electricity is produced every time the basin gate is closed and then opened. The main limitation of this energy form is that tides are periodic and are not very frequent when viewed in hour scales.
3. Wave Energy
You know waves and tides are entirely different. The basic difference between waves and tides is that waves are produced by wind and tides are caused due to the gravitational influence of the sun and moon. Although the waves are not as less frequent as tides, the limitation is that we cannot harness energy from all waves. There are certain criteria for positioning a wave energy station like sea depth, velocity, and the seasons, and it suits only a few places in the world.
4. Hydroelectric Energy
Hydroelectric energy is the most popular and most commonly used method. It is associated with water falls and dams. Water falling from a higher position to a lower position rotates the turbine that is kept through the water flow.
- In the current scenario, their practical efficiency is not comparable as that of conventional energy sources.
- Building power plants for these methods may become a negative externality such as possibly affecting the surrounding marine organisms or tourism.
- The cost of maintaining and building is high.
- They are complex and require high technical skills.
Note: Although these energy harnessing methods might not be reliable now, they might become a promising resource in the future.