Use of Auxiliary Engines
In ports, many ship staff run two auxiliary engines (diesel generators) in parallel to safeguard security of electric power supply. This is not needed for most of normal berth activities or when at anchor. When two engines operate in parallel, each run at very low loads thus give higher pollutant levels, consume more energy (they operate less efficiently) and the operation mode not good for engine components and maintenance.
Therefore, it is best practice if unnecessary cases of operation of two diesel generators can be minimized. This would equally reduce air pollutants to port as well.
To do this safely, the communication between deck department and engine department is crucial. If such communications are effective, then the engine room control engineers could pre-plan diesel generator operations in ports (MariEMS 2017).