Ocean energy is the term used to refer different types of ocean energy that is carried by oceans in various forms such as waves, tides, ocean temperature differences and salinity and these are classified mainly into two general forms namely thermal energy and mechanical energy. Ocean energy is the energy source that the world is looking forward to as a an alternative energy source capable of meeting the various energy requirements.
Thermal energy refers to the types of ocean energy that can be generated from oceans by making use of temperature differences and mechanical energy refers to other factors such as tides and waves.
OCEAN THERMAL ENERGY
This is one among the different types of ocean energy that is generated by making use of temperature differences between ocean’s, cooler deep, and warmer surface waters. The temperature difference is used to run a heat engine and to convert the thermal energy into useful work.
Ocean thermal energy ensures constant generation of electricity but are not economically feasible since the temperature differences in the ocean water is not considerably large. One of the major ocean thermal energy plant is the one set up at Japan that is overseen by saga university.
Tidal energy is a mechanical form of different types of ocean energy that helps in converting the energy carried by ocean tides into useful work. Tidal energy is mainly used for generating electricity and has wide potential for future electricity generation even though it is not yet widely used.
Due to the gravitational attraction by external celestial bodies on ocean water, ocean water tends to form bulges in water level leading to a temporary increase in sea level. This variation in sea level cause formation of tides in the shores and this variation are made use of for generating electricity.
The transport of energy by ocean surface waves is known as wave energy. Waves are created by winds and as long as the wave speed is lesser than that of the wind, a considerable amount of energy is transferred from wind to the wave and this transferred energy can be converted into electrical energy by various means such as propelling a turbine. Even though it is not yet widely used, wave energy is a promising alternative for the energy crisis that world is facing.
MARINE CURRENT POWER
The energy carried by ocean currents such as the Gulf Stream is termed as marine current power and has a considerable potential for future electricity generation. Just in the way a wind turbine extracts energy from wind, we can convert the kinetic energy of ocean currents into useful power and ocean currents are more predictable than wind.
Osmotic power is a one among the different types of ocean energy form that is available from the salt concentration difference between sea water and river water. Useful energy can be obtained from osmotic power by using reverse electro dialysis and pressure-retarded osmosis using specific membranes. The world’s first osmotic power plant was set up in Norway in 2009 and is capable of producing 4kW of energy and substantiates the significance of osmotic energy in future energy production methods.