Solar-Enhanced ocean thermal energy conversion for green liquid hydrogen production

A design, simulation, and optimization of a solar-enhanced ocean thermal energy conversion system for the
simultaneous production of power and liquid hydrogen are proposed. This study explores a novel approach to
enhancing ocean thermal energy conversion performance by integrating solar thermal collectors with nanofluids,
thereby augmenting the exergy efficiency and system economics. Incorporating solar thermal flat plate collectors
with nanofluid as an additional heat source increased power generation through the organic Rankine cycle. EES
software performs thermodynamic modeling, while data analysis uses artificial neural networks. The multiobjective
grey wolf optimizer algorithm is enacted to ascertain the most advantageous operational parameters
for the chosen working fluids of the organic Rankine cycle (R134a, R245fa, R290, and R600). The TOPSIS
decision-making method was then applied to assess and contrast the performance of working fluids. The findings
revealed that R245fa emerged as the supremely optimal working fluid, exhibiting the best performance among
the options considered. It achieved a peak exergy efficiency of 12.62 % alongside a maximal mass flow rate of
liquefied hydrogen production reaching 25.53 kg/h. The total investment rate is minimized to 383.38 $/h. The
associated study offers a foundation for further investigating and commercializing ocean thermal energy conversion
technology in the hydrogen energy sector.