Metro Mayor Steve Rotheram tells LBN the power of the Mersey tides was a big factor in not choosing electric propulsion for the new £26m Mersey Ferry – how does this claim stack up? Tony McDonough reports
Given Metro Mayor Steve Rotheram’s strong commitment to net zero it may have come as a surprise to some to learn the new £26m Mersey Ferry would not be electric-powered.
Instead the vessel, named Royal Daffodil and due to come into service in summer 2026, will be driven by a diesel-electric hybrid-ready engine using an Azipod propeller system.
This is a gearless, steerable propulsion unit where an electric motor is housed in a pod submerged outside the ship’s hull. It enhances fuel efficiency by improving maneuverability and reducing energy waste.
Certainly better for lower emissions than the two current ferries – Royal Iris and Snowdrop – but still not all-electric. Although the engine is adaptable for future conversion to full electric propulsion. So why not now?
LBN posed this question to the Mayor a few days ago at a media event at the Cammell Laird shipyard in Birkenhead, where the vessel is being built and where it was being transferred from the workshop to the wet dock.
Mr Rotheram told us: “It’s because of the power of the tides on the River Mersey. It can be converted over (at a later date). So that’s what we’re looking at.
“We’re looking at the next phase with this and what we can do on the river in regard to its power and how the ferry responds to that. Potentially we do have the ability to convert it to electric in the future.”
At between four and 10 metres, the Mersey Estuary has the second-highest tidal range (the difference between the lowest and the highest tides) in the UK. It is second only to the River Severn.
These conditions create powerful tidal streams, with velocities often exceeding 2-3 knots. This is why the Mayor is also pushing forward with his £6bn Mersey Tidal Power Project, installing a barrage across the river to generate clean electricity.
These strong tides mean vessels have to work harder, requiring more propulsion to maintain course, speed, and maneuverability – especially in confined channels or during docking and ultimately use up more energy.
This has caused problems on a fleet of 10 electric ferries introduced in Portugal in 2021. As well as the propulsion issues, charging the ferries sometimes takes too long and is often unreliable, leading to delays and cancellations.
One option would be to only operate Royal Daffodil in conditions where there are minimal currents. However, that is a non-starter. Mersey Ferries are workhorses that have to be used almost non-stop.
Not only do they operate a cross-river commuter service every weekday morning and evening, they are also used for daily hour-long tourist trips seven days a week and voyages up the Manchester Ship Canal lasting several hours.
It means with current battery technology the vessel would have to carry a very large battery and still face long charging periods. With the current schedule that would make it difficult.
However, battery technology is improving all the time and there may be a point when fast-charging becomes available on the Mersey.
There is also currently no ship-to-shore electric charging infrastructure on the river. Such an investment would significantly add to the cost of the new ferry project.