Sun's uneven heating of the earth's surface generates winds that drives waves in the ocean. Ocean waves contain in it a lot of energy. Ocean wave energy systems convert the kinetic and potential energy contained in the natural oscillations of ocean waves into electricity. Over the years a lot of mechanisms have been developed to harness the wave energy. Some of them are listed below based on their operating principles.
The European Marine Energy Center website below gives good animations for the different types of wave energy converters
http://www.emec.org.uk/marine-energy/wave-devices/
We also discuss about Tidal Barrage which makes use of the tidal variation at a specific location during the day. It acts like a dam storing the water during high tide, and then slowly releasing it back as during the low tide.
- Attenuator takes advantage of the wave steepness. It takes the shape of the wave and the energy used by the wave in doing so is converted to electricity.
- Point absorber works based on the wave height. They absorb the energy by heaving up and down.
- Overtopping devices concentrate and break the waves on them, capturing the surging water and using it to run a low head turbine.
- Oscillating water columns use the waves to pushup and down enclosed air in a hollow cylinder to run turbines.
- There are others which make use of the dynamic pressure induced by the waves.
The European Marine Energy Center website below gives good animations for the different types of wave energy converters
http://www.emec.org.uk/marine-energy/wave-devices/
We also discuss about Tidal Barrage which makes use of the tidal variation at a specific location during the day. It acts like a dam storing the water during high tide, and then slowly releasing it back as during the low tide.