PRESENTED BY
KUSHAGRA KHAMESRA

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OTEC
 Ocean thermal energy conversion, or OTEC, is a way to generate electricity using the temperature difference of seawater at different depths.
 The method involves pumping cold water from the ocean depths (as deep as 1 km) to the surface and extracting energy from the flow of heat between the cold water and warm surface water.
INTRODUCTION
 The oceans are continually heated by the sun and cover nearly 70% of the Earth's surface, this temperature difference contains a vast amount of solar energy which could potentially be tapped for human use.
 If this extraction could be done profitably on a large scale, it could be a solution to some of the human population's energy problems.
REQUIRMENT
 OTEC requires a temperature difference of about 36 deg F (20 deg C).
 This temperature difference exists between the surface and deep seawater.
 The cold seawater is an integral part of OTEC.
TYPES OF CYCLES
 On the basis of cycles it can be divided into three:-
 OPEN CYCLE
 CLOSED CYCLE
 HYBRID CYCLE
 Open-Cycle OTEC Flow Diagram
OPEN CYCLE
 Open-cycle OTEC uses the tropical oceans' warm surface water to make electricity.
 When warm seawater is placed in a low-pressure container, it boils.
 The expanding steam drives a low-pressure turbine attached to an electrical generator.
 The steam, which has left its salt behind in the low-pressure container, is almost pure fresh water.
 It is condensed back into a liquid by exposure to cold temperatures from deep-ocean water
RANKINE CYCLE (CLOSED CYCLE)
CLOSED CYCLE
 Closed-cycle systems use fluid with a low boiling point, such as ammonia, to rotate a turbine to generate electricity.
 Warm surface seawater is pumped through a heat exchanger where the low-boiling-point fluid is vaporized.
 The expanding vapour turns the turbo-generator.
 Then, cold, deep seawater—pumped through a second heat exchanger—condenses the vapor back into a liquid, which is then recycled through the system.
HYBRID CYCLE
 Hybrid systems combine the features of both the closed-cycle and open-cycle systems.
 In a hybrid system, warm seawater enters a vacuum chamber where it is flash-evaporated into steam, similar to the open-cycle evaporation process.
 The steam vaporizes a low-boiling-point fluid (in a closed-cycle loop) that drives a turbine to produce electricity.
 OTEC DESCRIPTION
OCEAN THERMAL ENERGY CONVERSION
 Ocean Thermal Energy Conversion (OTEC) is a means of converting into useful energy the temperature difference between surface water of the oceans in tropical and sub-tropical areas, and water at a depth of approximately 1000 metres which comes from the polar regions. For OTEC a temperature difference of 20oC is adequate, which embraces very large ocean areas, and favours islands and many developing countries.
SCHEMATIC DAIGRAM OF OTEC
FUTURE BENEFITS
 It is suitabale for base-loads.
 It can readily be provided–
food (aquaculture and agriculture);potable water;air conditioning; etc.
 Some floating OTEC plants would actually result in net CO2absorption.
APPLICATIONS
 ELECTRICITY
 DRINKING
 IRRIGATION
 COLD WATER REFRIGERATION
 AIR-CONDITIONING