Improving Engine Room Ventilation Systems: A Data-Driven Process Controller for Energy-Efficient, Variable-Speed Fan Operation in Marine Vessels

The capacity of engine room (E/R) ventilation fans installed in marine vessels is defined during the design stage based on the maximum air flow required by the main engine (M/E), diesel generators (D/Gs), and boilers. However, the vessel?s operating profile at reduced M/E power and speed does not justify the use of full capacities. In this article, a data-driven process controller is proposed to adjust the speed of E/R ventilation fan motors according to the variation of combustion air-flow and heat emission requirements to optimize energy efficiency during a ship's seagoing and cargo operation periods. The dynamics of the adaptive controller are established through parameter monitoring, regardless of the model of the controlled plant. For the tanker vessel under investigation, a case study initially defines the plant operational constraints and its power-saving potential. The proposed variable-frequency process control topology is then applied as a retrofit installation to the existing 18.5-kW E/R fan motor starters. Onboard experimental results show significant improvement in the vessel's power balance, D/G fuel consumption, and level of emission factors [carbon dioxide (CO
₂
), sulfur dioxide (SO
₂
), and nitrogen oxides (NO
_x
)], validating the performance of the proposed control topology, which is implemented using commercial programmable logic controllers (PLCs) and variable-frequency drive (VFD) units.