Global OTEC has designed first commercial-scale system to meet small islands’ urgent need for affordable, reliable renewable energy. It uses Ocean Energy Thermal Conversion – or OTEC – to convert the solar heat energy stored in the oceans into power. This means it doesn’t need to use any fossil fuels like oil, gas or coal to produce electricity.

The OTEC Barge generates clean energy using the difference in water temperature naturally present across the world’s tropical oceans. It works by using warm surface seawater to evaporate a fluid, which produces a vapour that spins a turbine. Cold water from deep in the ocean is then used to cool the vapour and condense it back into a liquid so the cycle can continue.

During an average day, the 60 million square kilometres on the surface of tropical oceans absorb one quadrillion megajoules of solar energy .

To release the same amount of energy through fossil fuels, you’d need to burn 170 billion barrels of oil!

In the tropics, the surface of the ocean remains at a consistent temperature of between 25 to 28 degrees celsius (°C).

However, way below the surface – around 800 metres deep – the water is fed by currents coming from the polar regions and remains a chilly 4°C.

OTEC resource map

OTEC works best in tropical equatorial zones where the temperature difference is at least 20°C year-round. This means OTEC’s affordable, clean energy is perfectly placed to support Small Island Developing States (SIDs).

“Global OTEC has developed a SIDS-Appropriate Technology that can harness SIDS largest renewable energy resource and assist to transform their energy sectors to achieve low-carbon economy’
Mr Osvaldo C.V. Abreu, Minister for Public Works, Infrastructure, Natural Resoruces and Environment. Government of São Tomé and Príncipe

What makes us different?

Global OTEC’s technology offers an environmentally friendly alternative to fossil fuels and provides clean baseload power all the time. Unlike many conventional renewables, it is also particularly suited to tropical islands and coastal cities because it requires significantly less space and generates power day and night, year-round. 

Landscape Slide

The OTEC Barge will:

Produce clean, renewable energy

 unlike solar and wind, which usually generates energy
around 20% to 30% of the time

Undercut diesel costs by 25% to 50%

to prevent impacts on energy security and free up government subsidies to be invested in climate adaptation and mitigation measures

one OTEC platform requires around 1/10th of the space needed for a solar plant to generate the same amount of energy

keeping the land free for agriculture, infrastructure
and biodiversity projects

in areas close to the equator with less intense or highly seasonal winds

than structures like wind turbines

like energy solutions such as geothermal

in a way that has been proven to work in other renewables