India is establishing its first integrated Ocean Thermal Energy Conversion (OTEC)–based desalination plant on Kavaratti Island in Lakshadweep.
The facility will simultaneously generate electricity and produce drinking water, marking a major step toward renewable energy adoption and water security in India’s island territories.
The project will supply around 1 lakh litres of potable water per day while generating approximately 60–65 kilowatts of electricity.
Key Highlights
| Feature | Details |
| Project | Integrated OTEC-based desalination plant |
| Location | Kavaratti Island, Lakshadweep |
| Developed by | National Institute of Ocean Technology (NIOT) |
| Ministry | Ministry of Earth Sciences |
| Electricity Generation | ~60–65 kW |
| Drinking Water Production | ~1 lakh litres per day |
This pilot project aims to improve freshwater availability and renewable energy generation in island regions.
What is an OTEC-Based Desalination Facility?
Ocean Thermal Energy Conversion (OTEC) is a renewable energy technology that uses the temperature difference between warm surface seawater and cold deep-sea water to produce energy.
The energy generated is used to operate desalination systems, converting seawater into potable water.
Core Principle
OTEC works on the thermal gradient between ocean layers.
| Water Layer | Temperature |
| Warm surface seawater | ~29°C |
| Cold deep-sea water | ~5°C |
Cold water is drawn from depths of around 1,000 metres, creating a temperature difference that drives power generation.
OTEC technology is most effective in tropical oceans, where this temperature difference is large.
Dual Output of the Plant
The Lakshadweep OTEC plant will provide two major outputs.
| Output | Details |
| Electricity | ~60–65 kilowatts |
| Freshwater | ~1 lakh litres per day |
Freshwater will be produced using Low-Temperature Thermal Desalination (LTTD) technology.
Infrastructure of Project
The plant requires specialised ocean infrastructure.
| Component | Description |
| Pipeline Length | 3.8 km |
| Material | High-density polyethylene (HDPE) |
| Purpose | To draw cold water from deep ocean layers |
This pipeline will transport cold seawater from depths of about 1,000 metres to the desalination facility.
Need for the Project
The project addresses several challenges in Lakshadweep’s water and energy systems.
Freshwater Challenges
Lakshadweep faces persistent water scarcity due to:
- Limited groundwater resources
- Salinity intrusion into freshwater sources
- Heavy dependence on seasonal rainfall
Energy Challenges
Currently, the islands rely heavily on diesel generator sets for electricity.
| Issue | Impact |
| Diesel-based power generation | High operational costs |
| Fossil fuel use | Environmental pollution |
| Fuel transport | Logistical challenges |
Advantages of the OTEC Plant
| Benefit | Explanation |
| Renewable Energy | Uses ocean temperature gradient |
| Self-sustaining | Electricity generated powers the desalination plant |
| Reduced Diesel Dependence | Less reliance on fossil fuels |
| Water Security | Reliable supply of drinking water |
| Environmental Benefits | Lower emissions compared to diesel generation |
The plant will function independently of grid electricity or diesel fuel.
Significance
- India’s first integrated OTEC-based power and desalination plant.
- Demonstrates the use of ocean-based renewable energy technologies.
- Addresses water scarcity and energy dependence in island territories.
- Supports sustainable development in Lakshadweep.
- Could serve as a model for other tropical island regions worldwide.