Ocean Thermal Energy Conversion (OTEC) 101

How Does It Work?

Ocean Thermal Energy Corporation (OTE) builds and operates clean hydrothermal energy plants worldwide using the proven technologies of Ocean Thermal Energy Conversion (OTEC) and Seawater Air Conditioning (SWAC).

Eighty percent of the sun’s solar energy is stored in the surface waters of the world’s oceans, and is replenished daily. OTEC taps into this energy by using the temperature difference between warm surface waters and the chilly deep ocean waters to produce steam. The steam turns a turbine, thus generating electricity. To see more detail on this process, see Figure 1 below.

What Makes OTEC Different?

Since OTEC is not dependent on any weather conditions, energy may be generated 24 hours a day, 7 days a week, 365 days per year. In addition, OTEC is much bigger than just renewable energy. It can be used to produce great volumes of fresh water for drinking and agriculture (see Figure 2). Our technology needs warm surface water, making tropical locations, which are also in desperate need of reliable energy and accessible clean water, ideal for implementation of this technology.

Economic Benefits

Reduced fuel imports

Stable utilities pricing

Reduced capital expense to Power Company and Government

Affordably increasable power usage

Reduced burden on existing utilities

Significant energy cost savings


Social Benefits

Affordable Fresh Water and Power

New industries/jobs/export opportunities (Aquaculture)

Diversifies fuel options and provides energy independence

World leadership role in eco-awareness


Environmental Benefits

Environmentally benign

Inexhaustible renewable energy from local resources

Fossil fuel avoidance – OTEC can save up to 15,000 bbls of oil per year per MW

Zero emissions – OTEC saves nearly 7,000 tons of CO2 per year per MW


Figure 1 - OTEC Power Production

  1. The sun-heated surface seawater flows through a Warm Water Pipe.
  2. The warm seawater boils a Working Fluid, creating steam. The steam drives the Turbine/Generator, producing electricity.
  3. The steam returns through the Heat Exchanger. It is then cooled by the chilly deep seawater brought in through the Cold Water Pipe and turns back into liquid. The cycle is repeated.
  4. After generating electricity, both the cold deep seawater and the warm surface seawater are returned to where they match the ocean’s temperature.

Figure 2 - Onshore OTEC Plant

  1. Power Generation: Ocean Thermal Energy Technology generates clean, renewable energy, 24 hours a day, without the use of fossil fuels.
  2. Refrigeration/Seawater Air Conditioning (SWAC): SWAC systems use the unlimited natural resource of cold, deep ocean water to cool buildings, reducing electricity usage by 80%-90% when compared to conventional AC.
  3. Desalination and Irrigation for Agricultural Applications: OTEC can use a portion of its electricity to operate adjoining water desalination plants, thus producing abundant volumes of water for drinking, aquaculture, and agriculture.