- OTEC (Ocean Thermal Energy Conversion) uses the temperature difference between warm surface waters and cold deep waters to drive a steam cycle and generate electricity. It has the potential to provide clean, renewable energy for tropical coastal regions. - There are three main types of OTEC systems: closed-cycle (uses ammonia), open-cycle (uses seawater), and hybrid-cycle (a combination). Closed-cycle generates electricity while open-cycle produces both electricity and fresh water. - While OTEC shows promise as a renewable energy source, the technology is still in development and demonstration stages. Large infrastructure is required that makes initial costs high. Environmental and engineering challenges also need to be addressed for widespread commercial

1. Arunamaheswari C
Assistant Professor
KCG College of Technology

2. Introduction
⚫The ocean cover 70% of the earth surface means ocean is
the world largest solar energy collector & energy stored
system.
⚫So, it possible to generate electricity from the oceanic
thermal energy?

3. What is OTEC..???
(Ocean thermal energy conversion)
⚫JacquesArsene d’Arsonval (1881)
⚫Energy convert –ocean solar radiation to electric power
⚫Renewable energy(clean & green power)
⚫Hydro energy thermal conversion system
⚫Use temp. differences

4. How does it work..???
⚫Fuel of OTEC..
⚫25-4 degree c (20 degree c differences)
⚫Used to drive steam cycle that turn to turbine
⚫Part of OTEC
⚫Require large volume
⚫Ex-100MW
20,000,000 gallon water
⚫Pump use 30% electricity

5. Type of OTEC-
1) Closed Cycle OTEC
2) Open Cycle OTEC
3) Hybrid Cycle OTEC

6. 1) Closed Cycle OTEC
⚫Warm & cold water
⚫Ammonia as working
fluid
⚫Generate electricity not
fresh water

7. 2) Open Cycle OTEC
⚫Seawater is working fluid
⚫Vacuum
⚫0.3 psia –22 degree c
(boiling point of water)
⚫Boiling water drive to turbine
⚫Give Production of electricity
& fresh water

9. Close Cycle Open Cycle

10. ⚫Combination of
Closed & Open
Cycle
3) Hybrid Cycle OTEC

11. Platforms of OTEC
1) Land Based Power plant

12. 2) Sea Based Power plant(Floating plant)

13. Potential of OTEC
⚫98 nations have been identified OTEC potential zone
⚫More potential for tropical countries(20-25 degree c)

14. Infrastructure & Cost
⚫Size-100MW…10mt pipe diameter
⚫Length required >1000 mt
⚫Big construction of plant
⚫Required skill & experiment
10MW(Landbased) coast-
40,000,000
10MW profit per/yr-10,000,000
100MW coast-215,000,000
profit-100,000,000
(Source-www.oteci.com/http://nelha.hawaii.gov/)

15. OTEC Products (Outputs)
⚫1) Electricity
⚫2) Fresh water
⚫3) SWAC
⚫4) Mari culture

16. 1) Electricity
⚫Able to provide continuously electricity
⚫Energy losses 20%-30%
2) Fresh water
⚫100MW -33,000,000 cubic mt per yr

17. 3) Mari-culture (fish production)
⚫Concentration of minerals, nutrients
⚫Artificial pond
⚫Very large profit
4) SWAC (Sea Water Air condition)
⚫SWAC require 1 cold pipe to reduce temp.
⚫Resort, Hotels, Hospitals, malls….
⚫ Reduce electricity
uses 80%-90% (AC)

19. OTEC Plant in World
Installed-
⚫Hawaii 1 MW -OTEC International and NELHA
⚫Japan/Nauru 120 kW- Japan Institute for Ocean Energy Research
⚫South Korea 20 kW- Installed in 2013. KISOT
⚫Japan/Okinawa 50 kW- XenesysIncorporated, IHI,and Yokogawa
Developing Stage-
⚫Hawaii 10 MW- Lockheed Martin Naval Facility Engineering Command
⚫Southern China 10 MW- Lockheed Martin, Reign wood Group
(India-Tuticorin 1 MW -Ammonia-based closed cycle, started in 2000, but not
completed due to problems with the pipes for pumping the seawater;floating
plant.(IIT))

20. Advantages
⚫Use clean, renewable, natural resource
⚫“0” Carbon emission (sometime little)
⚫Produce electricity as well as fresh water
⚫Reduce dependency on fossil fuel (1.3million barrel p/ye)
⚫Produce 120,000,000 litter fresh water p/day(100MW)
⚫Mariculture -70 tons of shellfish meat grow each
day(100MW)
(Johnson 2013)

21. Disadvantages/Limitations
⚫OTEC produced electricityat present some timecost more
than electricity
⚫OTEC plant not working further 40 degree latitude
⚫The pipe used in OTEC nearly up to 10 mtdiameter, there is
animal aresucked into the OTEC system.
⚫Risk of the leakageof Ammonia
⚫Cold waterdischargeon surface water itdangerous for
marine lifeex- Coral reefs
⚫OTEC –Experimental Stage

22. Ocean Thermal Energy Conversion (OTEC) is a technology solution
that directly addresses the key concerns of energy security, global
warming, pollution and depletion of nonrenewable fossil resources.
OTEC provides a clean, reliable energy solution for many areas of the
world.

23. Thank You