For ferries operating in the Greek islands, speed and manoeuvrability are non-negotiable. After replacing the engines on ro-ro passenger ship Ekaterini P, operator Fast Ferries also decided to upgrade to a new propulsion system in partnership with Wärtsilä.
Although the 1990-built Ekaterini P had been refurbished with new third-party engines after an engine failure, there was still room for improvement in the vessel’s performance. The long response time of the old fixed pitch propeller (FPP) was restricting the engine’s operation and leading to longer docking times during the vessel’s seven to eight daily port calls. The strong summer winds in the Aegean Sea, which require rapid thrust and power changes, had also become more challenging. Fast Ferries made the decision to replace the old FPP system with a new controllable pitch propeller (CPP) from Wärtsilä, enabling smoother engine operation and making it easier to cope with sudden load peaks.
The vessel needed to be back in action in time for the busy summer season, so there was a tight timeframe to complete the project. The Covid-19 pandemic brought additional challenges and meant an even stronger focus on safe ways of working. A new propulsion control system was needed that could interface with third-party components such as engines and gearboxes, and the new shaft-line installation had to be designed in such a way that no structural changes to the vessel would be necessary. Wärtsilä also had to account for the potential drop in performance that could have resulted from replacing five propeller blades with four.
To ensure maximum performance, Wärtsilä used computational fluid dynamics (CFD) to identify the optimal design, looking at how each piece of equipment performed individually as well as how they interacted with each other and with the ship’s hull. Advanced vibration studies ensured that the new propeller would not trigger any vibrational resonance in the vessel.
The CPP was also fitted with Wärtsilä’s energy-saving EnergoProFin propeller cap, which enables higher propulsion efficiency and reduced fuel consumption. This will make it easier for the vessel to comply with the IMO’s Energy Efficiency Ship Index (EEXI) and Carbon Intensity Indicator (CII) regulations. An automatic load control function was also included in the new propulsion control system to provide overload protection for the engines – especially useful during windy conditions, when the power demand from the engines fluctuates.
The project was completed on time and the CPP has improved the vessel’s manoeuvrability significantly. Furthermore, because the Ekaterini P can now take full advantage of her engine power, her transit speeds have also increased. During sea trials she achieved an impressive 21.5 knots.
“Wärtsilä’s optimised propulsion solution means we can now get the most from Ekaterini P while complying with the IMO’s stricter requirements. The vessel is now well-equipped to cope with the unique demands of the routes on which she operates. The whole project was performed very professionally and we’re looking forward to providing an even better service to our customers.
- Theologos Panagiotakis, Managing Director, Fast Ferries
Learn more about Wärtsilä lifecycle upgrades can help improve vessel performance.