FuelOpt: a smart way to derate engine power output and meet EEXI requirements

FuelOpt: a smart way to derate engine power output and meet EEXI requirements
Lean Marine’s FuelOpt system

Swedish propulsion optimisation expert Lean Marine is helping shipowners to comply with the recently introduced IMO Energy Efficiency Existing Ship Index (EEXI) with its FuelOpt technology.

FuelOpt has been on the market for almost a decade and works by limiting the shaft power output of a vessel without compromising safety in emergency situations that require full engine power.

Mikael Laurin, CEO at Lean Marine, explained: “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 optimisation, 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.

FuelOpt enables ship operators to set an upper limit to shaft power output without any modification to existing machinery, it 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.

Lean Marine’s FuelOpt is a propulsion control system implemented ‘on top’ of the existing control system or other systems on the bridge. It enables the ShaPoLi application by simply setting the upper shaft power limit in the system. 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 at 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.”

Transparent record keeping

FuelOpt provides a direct interface between the crew on the bridge and the machinery of the vessel, facilitating the control of speed, fuel consumption, engine power, or a combination thereof. To dynamically control vessel propulsion based on the command set, the FuelOpt system gathers vast volumes of 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 generated by FuelOpt and any information collected from other sources is integrated into the smart cloud-based performance management and reporting system, Fleet Analytics. When this data, particularly that of engine and shaft power, recorded by Lean Marine systems is combined with logbook and weather data, all the information needed to compile a power usage report becomes readily available. When, where and why excessive power may have been used during a certain event will be stated as mandated per the EEXI framework.