OTEC.pptx

thermal renewable energy ppt

1. OCEAN THERMAL ENERGY CONVERSION VIVEK CHAND I.D : 50489 M.Tech (Electrical Energy system ) 2022-2024

2. CONTENTS INTRODUCTION HISTORY OCEAN THERMAL ENERGY CONVERSION TYPES OF OTEC SYSTEM APPLICATIONS BENEFITS & DRAWBACKS OF OTEC FUTURE PROSPECTS CONCLUSION

3. INTRODUCTION Ocean Thermal Energy Conversion (OTEC) is a marine renewable energy technology that converts solar radiation to electrical power by using the temperature difference between deep cold ocean water and warm tropical surface water. Oceans cover more than 70% of Earth’s surface and captures a large part of the sun’s heat, making them the world’s largest solar energy collector.

4. HISTORY In 1881, Jacques d'Arsonval, a French physicist discovered tapping thermal energy of the ocean. Georges Claude, built the first OTEC plant in Cuba in 1930. Tokyo Electric Power Company built & deployed a 120 kW closed-cycle OTEC plant in 1981 on the Nauru island near south pacific ocean. In 2002, India successfully tested a 1MW OTEC plant near Tuticorin, Tamil Nadu.

5. OCEAN THERMAL ENERGY CONVERSION Ocean Thermal Energy Conversion (OTEC) is an electricity generation system.. In equatorial areas the temperature between the warm surface water and the deep cold ocean water differs by about 20°C. Bigger the temperature difference, the higher will be the efficiency. Power is converted to high voltage DC, and is cabled to shore for conversion to AC and integration into the local power distribution network.

6. MAIN COMPONENTS OF OTEC SYSTEM Water pipes (20inch radius) Heat exchanger ( Evaporator & Condenser) Turbine Generator

7. TYPES OF OTEC SYSTEM There are three types of OTEC system: Closed or Anderson Cycle OTEC System Open or Claude Cycle OTEC System Hybrid Cycle OTEC System

8. In the closed cycle, a working fluid, such as am m oni a , is pu m ped throu g h a heat exchanger (evaporator) and vaporized. This vaporized steam spins a turbine. The cold water found at the depths of the ocean condenses the vapor back to a fluid where it re t ur n s to the h e at ex c hanger (condenser). Evaporated fluids expands in turbine, which runs a generator to produce power. Boiling point of ammonia is (-33°C). CLOSED CYCLE OTEC SYSTEM

9. CLOSED CYCLE OTEC SYSTEM

10. OPEN CYCLE OTEC SYSTEM In open-cycle, the sea water is itself used to generate heat without any kind of intermediate fluid. W arm seawat er is exp a n d ed rapidly in a va c uum chamber where some of it 'flashes' to steam. This steam is used to drive a steam turbine. From the exhaust of the turbine, the vapor is condensed using cold seawater. Vapor expands and spins a turbine coupled to a turbo- generator to produce current.

11. SCHEMATIC OF OPEN CYCLE

12. HYBRID CYCLE OTEC SYSTEM A hybr i d c y c l e co m bines th e fea t ures o f the c l os e d - a nd open-cycle systems. W a rm seawa t er e nt e rs a v a cu u m cha m b e r a nd i s fla s h - evaporated, similar to the open-cycle evaporation process. The steam vaporizes ammonia, working fluid of a closed- cycle on the other side of an ammonia vaporizer. Vaporized fluid drives a turbine to produce electrical power. This f l u i d l e a ves the c o n d ens e r a nd i s p u m p e d t o t he evaporator to repeat the cycle.

13. OTEC system applications Hydrogen can be produced via electrolysis using electricity generated by the OTEC process. Desalination Desalinated water can be produced in open- or hybrid-cycle plants using  surface condensers  to turn evaporated seawater into potable water. System analysis indicates that a 2-megawatt plant could produce about 4,300 cubic metres (150,000 cu ft) of desalinated water each day.

14. OTEC system applications * Aquaculture Aquaculture  is the best-known by product , because  it reduces the financial & energy costs of pumping large volumes of water from deep ocean. Deep ocean water contains high concentrations of essential nutrients that are depleted in surface water due to biological consumption. This "artificial upwelling" mimics the natural upwelling that are responsible for fertilizing and supporting the world's largest marine ecosystems, and the largest densities of life on the planet. * Mineral Extraction The ocean contains 57 trace elements in salts and other forms and dissolved in solution. In the past, most economic analyses concluded that mining the ocean for trace elements would be unprofitable, in part because of the energy required to pump the water. The Japanese investigated the possibility of extracting Uranium. and found developments in other technologies (especially materials sciences) were improving the prospects.

15. BENEFITS Economic Benefits: Continuous supply of electricity throughout the year Reduced capital expense to power companies Life cycle cost savings Environmental Benefits: Reduces dependence on fossil fuels Zero emissions and it saves nearly 7000 tons CO 2 a year per MW.

16. DR A WBACKS  OTEC produced electricity at present would cost more than electricity generated from fossils fuels at their current costs.  No energy company put money in this project because it only had been tested in a very small scale.  Construction of OTEC plants and lying of pipes in coastal waters may cause localized damage to reefs and near-shore marine ecosystem.

17. Current operating Plants of OTEC In March 2013, Makai installed and operate a 100 kilowatt turbine on the OTEC Heat Exchanger Test Facility, and connect OTEC power to the grid. Okinawa Prefecture announced the start of the OTEC operation testing at Kume Island on April 15, 2013. The plant consists of two units; one includes the 50 kW generator while the second unit is used for component testing and optimization . In July 2014, DCNS group partnered with Akuo Energy announced NER 300 funding for their NEMO project. If successful, the 16MW gross 10MW net offshore plant will be the largest OTEC facility to date.

18. FUTURE PROSPECTS OTEC T echno l o g y has t he pot e ntial t o b e i nt e gra t e d with o t h e r commercial systems and products (e.g.- potable water and hydrogen). Energy and Economics can be enhanced by employing super efficient Hybrid Cycle OTEC system.

19. CONCLUSION Ocean Thermal Energy Conversion is a potential source of renewable energy that creates no emission s . It is fuel free. If proper research and development is carried on in this field we can satisfactorily fulfil the needs of the people and reduce our dependence on fossil fuels which contributes to large part of our energy requirement but is bound to be exhausted in a few years.

20. Thank You!