Performance improvement of ocean thermal energy conversion organic Rankine cycle under temperature glide effect

The temperature glide effect of zeotropic mixtures on ocean thermal energy conversion (OTEC) cycle driven by a narrow difference, which is significantly different from that in conventional low-grade technologies, yet to be thoroughly studied. In this study, the binary mixtures-based OTEC investigated. Comparative analysis classical ORC and six types ORCs configured with or without series/parallel multi-pressure evaporators single-/dual-outlet liquid-separated condensers were conducted. results showed could beneficial conversion. Multi-pressure evaporation reduce irreversible loss heat exchanger, series evaporator-based (SMZO) performed better than parallel (PMZO), 0.09%–0.14% higher efficiency, 2.27%–3.11% turbine power output, 0.89%–1.46% exergy efficiency. Liquid-separated condensation improve increasing transfer coefficient, dryness dominant performance. Dual-outlet also increase cycle-levelised cost. Comparingly, single-outlet based levelised cost 7.93% 4.81%, respectively.