Ocean Thermal Energy Conversion (OTEC) Project

Union Minister for Earth Sciences Jitendra Singh reviewed the progress of an Ocean Thermal Energy Conversion (OTEC) project during his visit to Kavaratti in Lakshadweep. The project aims to generate renewable energy while addressing the region’s persistent freshwater shortages.

About OTEC Technology

OTEC is a technology that produces energy by harnessing the temperature difference between warm surface seawater and cold deep ocean water. In tropical regions, solar heating makes the surface water significantly warmer than deeper layers, creating a thermal gradient that can be used to generate electricity.

OTEC systems typically require a temperature difference of at least 20°C to operate efficiently. In the process:

• Warm surface seawater passes through an evaporator containing a working fluid with a low boiling point.
• The fluid vaporizes and drives a turbine connected to a generator, producing electricity.
• The vapour is then condensed back into liquid using cold seawater pumped from deep ocean layers.

Some OTEC systems also use seawater itself as the working fluid, and the condensation process produces desalinated freshwater.

Purpose of the Lakshadweep Project

The electricity generated through the OTEC system will power desalination plants, ensuring a stable and sustainable supply of drinking water for island communities. The project addresses long-standing freshwater challenges in Lakshadweep caused by:

• Limited groundwater resources
• Salinity intrusion in aquifers
• Heavy dependence on seasonal rainfall

Unlike solar or wind energy, the OTEC-based system can function continuously, providing a reliable renewable energy source.

Expected Benefits

The initiative could eventually reduce dependence on diesel-powered desalination units, lowering fuel transportation costs, cutting emissions, and ensuring uninterrupted freshwater supply to the islands.

Globally, India is among the pioneers in developing OTEC technology, with similar experimental projects and collaborations involving countries such as Japan and the United States.

Sources: PIB & EIA