Research on Ocean Thermal Energy Conversion System Based on Supercooled Thermal Energy Storage

LU Henglin; SHA Haonan; JIANG Dongyue

doi:10.11993/j.issn.2096-3920.2025-0155

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LU Henglin, SHA Haonan, JIANG Dongyue. Research on Ocean Thermal Energy Conversion System Based on Supercooled Thermal Energy Storage[J]. Journal of Unmanned Undersea Systems. doi: 10.11993/j.issn.2096-3920.2025-0155

Citation:

LU Henglin, SHA Haonan, JIANG Dongyue. Research on Ocean Thermal Energy Conversion System Based on Supercooled Thermal Energy Storage[J]. Journal of Unmanned Undersea Systems. doi: 10.11993/j.issn.2096-3920.2025-0155

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Research on Ocean Thermal Energy Conversion System Based on Supercooled Thermal Energy Storage

doi: 10.11993/j.issn.2096-3920.2025-0155

1.
School of Energy and Power, Dalian University of Technology, Dalian 116000, China
2.
No. 703 Research Institute of CSSC, Harbin 150000, China

Received Date: 2025-11-12
Accepted Date: 2025-12-30
Rev Recd Date: 2025-12-27

Available Online: 2026-03-17

Abstract

Abstract

To address the limited endurance of underwater unmanned systems such as underwater gliders (UGs), an ocean thermal energy conversion system coupling supercooled phase change materials (EPCM) with thermoelectric modules (TEM) is proposed and experimentally validated. By maintaining EPCM in a supercooled liquid state during descent and triggering spontaneous crystallization with latent heat release in cold seawater, a stable temperature difference is established across the TEM, enabling direct conversion of ocean thermal gradient energy into electrical power. Three EPCMs with different compositions and a mass of 2.5 kg were prepared, and their supercooling stability and power generation performance were evaluated under simulated sea surface–deep sea thermal conditions. The results show that the EPCM composed of 98% calcium chloride hexahydrate (CCH) and 2% PEG200 exhibits more stable supercooling and latent heat release behavior. Under deep-sea conditions, the system achieves a maximum open-circuit voltage of 15.2 V, a maximum short-circuit current of 43.06 mA, a power generation duration of approximately 2640 s, and a single-cycle energy output of 518.09 J. During a complete descent–ascent profile, the cumulative electrical energy output reaches 821.44 J, corresponding to a volumetric energy density of 547.63 kJ·m⁻³. The results demonstrate that the proposed system can provide stable energy output within a single dive cycle and shows promising potential for autonomous energy supply in underwater unmanned systems.
- Ocean temperature difference energy,
- thermoelectric generators,
- supercooled phase change materials,
- underwater gliders

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References(25)

References

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