The last decades, the international shipping has been considered a large and rising source of emissions globally. The International Maritime Organization adopted strict regulations (2020) for emission levels, especially for ships operating in Emission Control Areas (ECA). The 2020 regulation will enforce a global sulphur oxide (SOx) emission limit of 0.5% while the limit in the ECA zones is 0.1% since 2015. The ship owners will be forced to reduce the environmental impact of their activities. Switching to a lower sulphur fuel oil is the simplest method to follow and implies the lowest capital cost invested. However, special attention should be considered while switching from one fuel to another. This procedure is also known as changeover. The plurality of ship operators proceeds to manual changeover which can negatively affect the components in the fuel oil system (pumps, injectors, purifiers etc.).&nbsp;Hence, the aim of the project is the development, optimization and simulation of a cost-effective automated fuel oil management unit to execute safely the changeover procedure. The project consists of a retrofit feasibility study and report on a modern oil tanker including the 3D model of the unit in Autodesk Inventor. Moreover, the mathematical modelling of the system is established and coded in National Instruments LabView to optimize the changeover procedure. Furthermore, the simulation of the system has been also achieved through a developed physical model (automation panel). The physical model emulates the system with real-time input measurements (i.e. temperature sensor), a programmable logic controller (PLC) and a touch panel, where the process is presented. The system is programmed to operate safely according to the manufacturer needs and redundant under emergency situations to avoid wear in the engine components.