You probably know that one of the main constraints of solar power is the cost it involves to make the energy collectors and the vast acreage it consumes in setup. But did you realize that nature has its very own natural solar collector in the form of water?
The ocean makes up most of the earth’s surface and located throughout the equatorial zone, the tropical oceans store sufficient solar energy in its upper layers to power over 300 times the world’s present electricity consumption.
Sea solar power works on the science of Ocean Thermal Energy Conversion (OTEC) or Ocean Thermal Energy (OTC) for short.
In OTC, electricity is generated through the manipulation of temperature differences between the waters drawn from the ocean’s sun-warmed surface and frigid inner depths.
There are essentially 10 major elements to the OTC system. They are the:
- Integrated floating structure/plant/ship,
- warm water pump,
- cold water pump,
- cold water pipe,
- working refrigeration fluid (propylene),
- working fluid pump;
- vapour turbine generator;
- electric cable to shore;
- boiler;
- condenser
Much like a solar power plant, the ocean solar power plant relies on the energy of the sun to create the vapour that will run the turbine generator to generate electricity.
The stationary floating structure will be responsible to skim off a small percentage of the heated ocean surface layer. That solar heated water is then pumped into the boiler to function as the heat source where the working refrigeration fluid, propylene is easily converted into high pressure vapour.
The vapour will then be channelled into the turbine where electricity is generated before flowing into the condenser, where frigid water, pumped from the lower depths of the ocean will work to return the vaporised propylene back into its liquid state, where it can then be redirected back into the boiler for reuse. The electricity will be transmitted to shore (power grid) via the underwater electric cables.
Now another beauty of the OTC system is its by-products. Not only are they harmless to the environment, they are downright beneficial! Just to name a few, the OTC system would results in the generation of:
- Delightful tasting desalinated ocean water, usable as drinking water or for agricultural purposes
- Fertilization of ocean surface layers with nutrients/food for the fishes as the rich cold water from the ocean’s depths are pumped out from the plant.
And there you have it, the basic mechanism behind Ocean Thermal Energy Conversion, another wonderful nature inspired technology that goes to show us the earth was designed to sustain itself.
