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Monday, March 29, 2021 

Swedish propulsion optimisation company Lean Marine says that its FuelOpt system can help shipowners comply with the recently introduced IMO’s Energy Efficiency Existing Ship Index (EEXI).

The cost-effective technology, which has been on the market for almost a decade, works by limiting the shaft power output of a vessel without compromising safety in emergency situations that require full engine power. 

According to CEO Mikael Laurin: “Shaft power limitation (ShaPoli) can be achieved through our FuelOpt system as suggested in the current EEXI framework. This functionality has been part of FuelOpt since the system was created in 2013. We are happy to confirm that it complies with the upcoming regulations and are looking forward to working with our clients to implement this feature onboard of their vessels.”

The EEXI, which was introduced in November 2020 by the IMO as a measure to combat GHG emissions from shipping, is likely to come into force in 2023. It follows the calculations of the Energy Efficient Design Index (EEDI) with some adaptations for existing vessels. There are a number of suggested improvement measures to meet efficiency targets including engine power limitation (EPL) or shaft power limitations (ShaPoLi), propulsion optimization, energy-saving devices and more.

Among these measures that can be achieved by EPL or ShaPoLi, derating the engine power output is likely to be the primary and most efficient measure to reduce GHG emissions.

By enabling an upper limit to shaft power output without any modification to existing machinery, FuelOpt aligns operations with EEXI requirements. Additionally, the system can be overridden in an emergency, thereby enabling access to the engine’s full power. The system logs all necessary engine parameters and stores these in Lean Marine’s Fleet Analytics, where reports can be created.

FuelOpt™ is implemented ‘on top’ of the existing control system or other systems on the bridge. When the system is activated, FuelOpt will ensure that the vessel does not exceed this power limit via any commands set during the voyage or due to varying environmental conditions. In this way, the shaft power limitation would be executed in daily operations as stipulated in the EEXI requirements.

Anders Bergh, Technical Sales Manager, Lean Marine said: “In addition to being compliant with the ShaPoLi requirements, our propulsion automation system FuelOpt is also beneficial in its ability to minimise the impact of engine or shaft power limitations on daily operations. FuelOpt dynamically optimises a vessel’s propulsion line in real-time by making sure that the engine and propeller operate at optimal conditions based on the commands or limitations set.”

To dynamically control vessel propulsion based on the command set, the FuelOpt system gathers vessel data in real-time from signals onboard (e.g. GPS, speed log, fuel consumption, alarm signals...), particularly from the propulsion line and the engine, including shaft torque meter(s) and RPM sensor.

Data is integrated into the cloud-based performance management and reporting system, Fleet Analytics, so that all the information needed to compile a power usage report becomes readily available.

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