6 March 2026·PIB

Dr. Jitendra Singh Reviews “Low Temperature Thermal Desalination (LTTD) plant” in Lakshadweep Emphasises Role of Ocean Technology in Water Security

In this note

1. At a Glance

Low Temperature Thermal Desalination (LTTD) is an indigenous Indian ocean-technology that converts seawater to potable water by exploiting the temperature gradient between warm surface and cold deep-sea water [1][2].
Developed by National Institute of Ocean Technology (NIOT), Chennai, under the Ministry of Earth Sciences (MoES) [1][2].
Strategic significance for UPSC: intersection of water security, S&T self-reliance, island UT governance, and blue economy [1].

On 6 March 2026, Union Minister for Earth Sciences & S&T Dr. Jitendra Singh visited the LTTD plant at Kavaratti, Lakshadweep, reviewed functioning of desalination facilities and took stock of an upcoming OTEC-powered desalination facility at Kavaratti [1][2].

LTTD principle demonstrated by NIOT; first plant commissioned at Kavaratti (2005) with 1 lakh litre/day capacity [3].
Subsequently extended to Minicoy and Agatti — three pioneer LTTD plants at 1 lakh L/day each [3].
MHA, through UT Lakshadweep, sanctioned 6 more plants (Amini, Androth, Chetlat, Kadmat, Kalpeni, Kiltan) at 1.5 lakh L/day [3].
Indigenously developed — replaces imported RO-based desalination in remote island contexts [3].

Technology: LTTD — warm surface seawater flash-evaporated at low pressure; vapour condensed using cold deep-sea water (~7–15 °C) drawn from ~600–1000 m depth [1][3].
Implementing agency: NIOT, an autonomous body under MoES (not MoEFCC, not Jal Shakti) [1][3].
Location of NIOT: Pallikaranai, Chennai [3].
Capacity per plant: 1 lakh L/day (older); 1.5 lakh L/day (newer 6 plants) [3].
Islands covered (8): Kavaratti, Minicoy, Agatti, Amini, Kalpeni, Kadmat, Chetlat, Kiltan [2].
Funding/coordination: MoES (tech) + MHA via UT Administration of Lakshadweep (deployment) [3].
Future tech: Ocean Thermal Energy Conversion (OTEC)-powered desalination plant at Kavaratti under development [2].

Scientific/Technological: First operational LTTD plants globally at island scale; no chemicals/membranes needed (unlike Reverse Osmosis); low pre-treatment; uses thermal gradient — abundant in tropical seas [1][3].
Social: Reported decline in water-borne diseases and year-round reliability of drinking water in Lakshadweep; addresses acute freshwater scarcity (groundwater saline; rainwater seasonal) [2].
Environmental: Low energy footprint vs. RO; no brine concentrate dumping issue at same magnitude; supports SDG-6 (clean water) [1].
Strategic: Strengthens habitation viability of strategic island chain in Arabian Sea near 9° Channel; aligns with Deep Ocean Mission and Blue Economy policy [1][2].
Administrative: Centre-UT model — MoES (R&D) + MHA (deployment) + UT (operations); template for replication in A&N Islands [3].

6 March 2026: Minister's site review at Kavaratti; pitched ocean technology as pillar of water security [1].
Review meeting with NIOT scientists on OTEC-powered desalination at Kavaratti [2].
8 islands now have operational LTTD plants [2].

LTTD uses temperature difference between surface and deep-sea water — NOT reverse osmosis [1].
Developed by NIOT (National Institute of Ocean Technology), Chennai [1].
NIOT is under Ministry of Earth Sciences (not Ministry of Jal Shakti, not DST) [1].
First LTTD plant: Kavaratti, Lakshadweep [3].
Capacity of first three plants: 1 lakh litres/day each [3].
Six newer plants approved at 1.5 lakh litres/day [3].
Six new locations: Amini, Androth, Chetlat, Kadmat, Kalpeni, Kiltan [3].
LTTD operational across 8 Lakshadweep islands as of 2026 [2].
OTEC = Ocean Thermal Energy Conversion — upcoming at Kavaratti [2].
Union Minister (MoES + MoS S&T, independent charge): Dr. Jitendra Singh [1].
Reviewed on 6 March 2026 [1].
Cold deep-sea water drawn typically from ~600–1000 m depth [3].
LTTD does NOT use membranes (distinguishes from RO) [3].
Deployment funded by MHA through UT Lakshadweep administration [3].

GS-III: Science & Technology (indigenous tech, applications); Environment (water resources, sustainability); Infrastructure.
GS-II: Government policies — Centre–UT coordination; welfare of island populations.
GS-I: Geography — distribution of water resources; ocean phenomena.
Probable stems:
"Discuss the role of ocean technologies such as LTTD and OTEC in ensuring water and energy security for India's island territories."
"Indigenous desalination is more than a technology — it is a strategic asset for India's island UTs. Critically examine."
"Compare LTTD with Reverse Osmosis as desalination pathways in the Indian context."

Deep Ocean Mission — flagship MoES programme; LTTD/OTEC are components.
National Institute of Ocean Technology (NIOT) — mandate, projects (Samudrayaan, ROSUB).
Ocean Thermal Energy Conversion (OTEC) — same thermal gradient, for power.
Blue Economy Policy Framework — water, energy, biodiversity, shipping.
Jal Jeevan Mission — contrast: rural piped water vs. island desalination.
Lakshadweep UT governance — coral atolls, fragile ecology, Praful Patel administration.
Reverse Osmosis desalination — Tamil Nadu (Minjur, Nemmeli) plants for comparison.
SDG-6 (Clean Water & Sanitation) — India's reporting framework.

Wrong ministry: NIOT falls under MoES, not Ministry of Jal Shakti or DST.
Confusing LTTD with RO — LTTD is thermal/phase-change, RO is membrane/pressure.
Confusing NIOT with NIO — NIO (National Institute of Oceanography, Goa) is under CSIR; NIOT (Chennai) under MoES.
Assuming LTTD plants exist beyond Lakshadweep — operational deployment is Lakshadweep-only so far.
Misstating capacity — 1 lakh L/day original; 1.5 lakh L/day the newer six.