Ocean Thermal Energy — LUMARE

Ocean Thermal Energy (OTEC)

How It Works

OTEC generates power by utilising the ocean thermal. A working fluid (refrigerant) is warmed up by the warm seawater from the sea surface until it becomes vapour to drive the turbine. The vapour is then cooled back into a liquid form by using the cold water from the deep sea, making it a continuous cycle.

To make it work, it needs:

Warm surface seawater (>27°C)
Cold Deep Sea Water (< 7°C) from 600-1000m depth, not too far from the coast (< 20km from shore, the closer the better).

It Can Be Located Onshore or Offshore

OTEC can be onshore (beachfront) or offshore (with a repurposed barge or offshore oil platform). For our pilot project, LUMARE selected the Onshore concept due to several considerations, i.e. construction and operational simplicity.

We need at least 20°C or more temperature differences between the warm and cold seawater. If the surface of the sea is 24°C then we need the Deep Sea Water to be at least 4°C, which is at the depth of around 800-1000m deep. The distance of the water depth of 800-1000m needs to be no further than 20km from the seashore for OTEC to be operable.