1. Lexi wise 8W2

2. OTEC Ocean Thermal Energy Conversion

3. Definition Ocean Thermal Energy Conversion (OTEC) is a process that can produce electricity by using the temperature difference between deep cold ocean water and warm tropical surface waters. OTEC plants pump large quantities of deep cold seawater and surface seawater to run a power cycle and produce electricity.

4. HISTORY OTEC technology is not new. In 1881, Jacques Arsene d'Arsonval, a French physicist, proposed tapping the thermal energy of the ocean. But it was d'Arsonval's student, Georges Claude, who in 1930 built the first OTEC plant in Cuba. The system produced 22 kilowatts of electricity with a low-pressure turbine. In 1935, Claude constructed another plant aboard a 10,000-ton cargo vessel moored off the coast of Brazil. However, weather and waves destroyed both plants before they became net power generators. (Net power is the amount of power generated after subtracting power needed to run the system.)

5. How Does OTEC Work? OTEC uses the ocean's warm surface water with a temperature of around 25°C (77°F) to vaporize a workingfluid, which has a low-boiling point, such as ammonia. The vapor expands and spins a turbine coupled to a generator to produce electricity.

6. Benefits of OTEC The key benefits of OTEC include the following: ●OTEC systems produce fresh water and electricity as well, which is highly beneficial for island regions where fresh water availability is limited. ●It makes use of renewable, clean, natural resources. Fossil fuels are replaced by warm surface seawater and cold water from deep sea to generate electricity. ●OTEC plants do not pollute the ● environment by releasing carbon dioxide emissions or other polluting substances. ●It helps reduce the country’s dependence on imported fossil fuels.

7. Disadvantages of OTEC Some of the major drawbacks of OTEC include the following: ●Construction of OTEC plants and pipes in ocean may cause damage to onshore marine ecosystems and reefs. ●As this technology has been tested only in small-scale, it is not feasible for an energy company to invest in this project. ●Electricity produced from OTEC would currently cost more than that produced from fossil fuels. ●Discharging of cold and warm sea water needs to be carried out several metres away from the shore to avoid any dwelling impact on marine ecosystems. ●Energy required to pump the sea water from depths may be huge, which otherwise need a diesel generator.