Zero-Carbon Adsorption Cooling System Optimization for Maritime Transport Using MOF-303

Global warming is already producing serious and wide-ranging impacts on climate systems, ecosystems, and human societies, with many changes expected to persist for centuries. Human activities remain the dominant driver of these effects, and urgent measures are required to mitigate their consequences. Maritime transportation, which currently carries nearly 80% of global goods, is among the most energy-efficient modes of transport, yet further improvements are needed to reduce its carbon footprint. Cooling demand alone accounts for 10–30% of total shipboard energy consumption, particularly for passenger spaces, refrigerated cargo, and food products. This study proposes a zero-carbon adsorption cooling system powered by waste heat represented in exhaust gases and seawater for cooling, thereby addressing both environmental sustainability and operational efficiency. A dynamic model was developed to investigate the performance of an adsorption cycle employing MOF-303, a highly water-selective metal–organic framework with superior uptake capacity and kinetics compared with conventional silica gel or zeolite. Parametric studies examined the influence of half-cycle duration, driving hot-water temperature, and sorbent mass on coefficient of performance (COP), specific cooling power (SCP), and cooling capacity. Results indicate that short cycle times maximize throughput but limit efficiency, whereas long cycles enhance COP and freshwater yield at the expense of cooling power. An optimal operating window was identified at intermediate cycle times (500-700 s), delivering a maximum SCP of 421 W/kg and a cooling capacity of 16.8 kW. Similarly, hot-water inlet temperatures of 85–90 °C and sorbent inventories of 20–23 kg provided the best compromise between efficiency, compactness, and output. The findings confirm that MOF-303 adsorption systems can effectively harness marine waste-heat streams to deliver sustainable cooling, offering a practical pathway toward zero-carbon maritime transport.