Utilizing the temperature difference between warm surface waters and cold deep waters to generate electricity

Harnessing the energy from ocean waves

Extracting energy from ocean currents

Capturing the energy from ocean tides

Closed-cycle OTEC and Open-cycle OTEC

Horizontal-axis OTEC and Vertical-axis OTEC

Single-stage OTEC and Multi-stage OTEC

Direct-contact OTEC and Indirect-contact OTEC

Seawater

Ammonia

Propane

Butane

To convert seawater into steam

To condense the working fluid

To transfer heat from the warm surface water to the working fluid

To generate electricity

To convert steam into seawater

To transfer heat from the working fluid to the cold deep water

To generate electricity

To control the flow of the working fluid

To generate electricity

To convert steam into seawater

To transfer heat from the working fluid to the cold deep water

To control the flow of the working fluid

It is a renewable and sustainable source of energy

It does not produce greenhouse gases

It is a cost-effective technology

It is easy to implement and maintain

High capital costs

Low efficiency

Environmental concerns

Technical complexity

United States

Japan

France

China

Nauru OTEC Plant

Hawaii OTEC Plant

Kahe Point OTEC Plant

Ocean Thermal Energy Corporation Plant

Electricity generation

Desalination

Hydrogen production

Air conditioning

5-10 °C

15-20 °C

25-30 °C

35-40 °C

Evaporator

Condenser

Turbine

Solar panels

2-5%

5-10%

10-15%

15-20%

Temperature difference between warm and cold waters

Flow rate of the working fluid

Efficiency of the turbine

Wind speed