- Why in news
- On 6 March 2026, Union Minister Dr. Jitendra Singh inspected the ongoing OTEC-based desalination plant at Kavaratti, Lakshadweep, and reviewed its progress and commissioning timelines.
- What it is
- Ocean Thermal Energy Conversion uses the temperature gap between warm surface seawater and cold deep seawater to drive a turbine and generate power. The Kavaratti plant uses this energy to run desalination units that make drinking water. It is meant to give islands a steady, clean source of water and energy.
- Working principle
- The plant uses the temperature difference between warm surface water and cold deep-sea water to generate energy, which runs desalination.
- Key components
- Components reviewed include the seawater intake, deep-sea cold-water pipeline, turbine-generator unit and desalination modules.
- Continuous source
- Unlike solar or wind, OTEC is designed to run continuously, independent of weather.
- Deep Ocean Mission link
- Officials briefed the Minister on plans for an offshore OTEC demonstration project under the Deep Ocean Mission.
- Site challenges
- Coral formations, rocky strata, trenches and narrow monsoon work windows complicate construction in Lakshadweep.
- Ministry
- The Ministry of Earth Sciences is the nodal ministry for ocean technology and the Deep Ocean Mission.
Don’t confuse with OTEC vs tidal energy: OTEC uses the temperature gradient between surface and deep water; tidal energy uses the rise and fall of tides.
Don’t confuse with Open-cycle vs closed-cycle OTEC: Closed-cycle uses a working fluid with a low boiling point; open-cycle flashes warm seawater to steam and can yield desalinated water.
Science and technology: 57 Prelims questions since 2013; most test the concept behind the news, not the news itself. In Mains, 12 news-triggered questions.
Why it matters
- Gives islands a continuous clean source of power and drinking water, unlike intermittent solar or wind.
- Can cut diesel use, fuel transport costs and emissions on islands.
- Supports the Blue Economy and energy security goals.
Problems
- Difficult seabed of coral, rock and trenches, with rough seas and short monsoon work windows.
- Technology is at a demonstration stage, so costs and scalability are uncertain.
- Deep-water intake and discharge need environmental safeguards for marine ecosystems.
Way forward
- Complete commissioning with monitoring of environmental impacts, then move to the offshore demonstration under the Deep Ocean Mission.
- Use lessons to replicate the model in other tropical islands and coastal areas.
Put in your answer
Kavaratti OTEC plant: An example of ocean-based renewable energy linked to desalination for island water security.
Blue Economy framework: The project is cited as part of efforts to promote ocean-based technologies and climate resilience in islands.
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- 2014Mains GS1 · Q24Critically evaluate ocean resources that can be harnessed for world resource crisis.
UPSC’s own questions that come close to this issue, from our Prelims and Mains banks.
No practice question for this one; the card may still help an answer. Why: OTEC is a lasting science concept; sci-tech is 17% of news-linked Prelims questions. Release gives few hard facts, so no question.
Worth revising until Prelims 2027: most news questions come within two years of the event.