VESSEL REVIEW | Orbit Clipper – London operator's new cross-river electric ferry with auto-docking capability

UK operator Uber Boat by Thames Clippers will soon place a new electric catamaran commuter ferry into service on the River Thames.

Built by Wight Shipyard, Orbit Clipper is the first in a new series of all-aluminium, double-ended, cross-river ferries that can transport up to 150 passengers and 100 bicycles and that feature a Ro-Ro design to enable automated docking on both sides.

The ferry was developed in fulfilment of a need for a zero local-emission vessel that would facilitate a new pedestrian and bicycle link between London's Canary Wharf on the north side of the Thames and Rotherhithe on the south, as there had been a lack of river crossings east of Tower Bridge.

“The vessel needed to have good manoeuvrability with minimal power output due to the challenging berthing environment and continuous full day operating cycle,” Sean Collins, CEO and Co-Founder of Uber Boat by Thames Clippers, told Baird Maritime. “A minimal draught was required to deal with the shallow water on the south shore.”

Collins added that a key focus was the reduction in the mooring time between the boat and the pier to, “create a more efficient crossing, which in turn will allow a better frequency and customer experience.” To that end, a new auto-mooring system was introduced.

“The vessel also needed to be of an iconic design to fit well with the evolving London architecture and to make it easily identifiable as cross river services expand in the future,” said Collins.

Ensuring a balance between stability, light weight, and long battery endurance

Orbit Clipper has an LOA of 25 metres (82 feet), a beam of 10 metres (32 feet), a draught of only 1.06 metres (3.48 feet), a moulded depth of 2.3 metres (7.5 feet), and a displacement of 72.8 tonnes at full load.

The ferry is operated by only two crewmembers while the propulsion setup includes an EST-Floattech 960kW battery pack driving 150kW electric motors connected to Hydromaster azimuthing thrusters. CCTV cameras are fitted to assist the crew in berthing and to provide them a general overview of the vessel.

The vessel will cross the Thames between Canary Wharf and Rotherhithe every 10 minutes from each side on weekdays and every 15 minutes on weekends. To facilitate this, Aqua Superpower installed a dedicated overnight battery charging station at Canary Wharf.

According to Collins, the vessel will provide the only dedicated and accessible form of crossing for cycle access east of Tower Bridge.

“The operational river conditions have significant tidal range and low water draught, meaning the balance between draught, battery weight and therefore stability were crucial elements to overcome,” company COO Geoff Symonds commented.

“The vessel will require 18 hours of continuous passenger service, so the batteries needed to have sufficient range, for this was a key consideration when looking at the design and weight of the vessel.”

Symonds added that the vessel needed to receive an automated docking system, which was a major contributing factor to reducing power usage over its operating day. The challenge therefore was in ensuring that the vessel would be able to operate on a floating berth within a busy and turbulent area of the river.

Collins remarked challenges were also encountered in relation to the lead time for key components associated with the vessel’s electrification and in satisfying the various regulatory authorities for a first-in-class concept.

“Once we got over the initial hurdles and clarification as to what was required for the build, the biggest challenge was the interface with the floating docks/land interface,” Collins told Baird Maritime. “Also, we quickly learnt that the knowledge and understanding for this sector is still in the early days and constantly evolving.”

Automatic mooring coupled with enhanced manoeuvrability

Symonds explained that the choice of propulsion was an iterative process building on the earlier design work from an initial feasibility study.

“Our aim was to have the greatest propulsive efficiency to minimise energy consumption whilst providing the vessel with the best manoeuvrability against requirement of shallow water operation and potential river debris,” said Symonds.

“The final choice was Hydromaster azimuthing thrusters, which gave the best balance compared to directional waterjet and other azimuthing thruster options.”

Symonds said the chosen thrusters are conventional and developed technology. However, to achieve the shallow draught with the catamaran hull configuration, the thrust is masked by the catamaran hulls in positions of 45 degrees “abaft” the beam.

“As such, haptic feedback has been incorporated into the master’s controls to indicate positively thruster positions which are inefficient/undesirable.”

Symonds remarked that, whilst not part of the propulsion, the auto-mooring system aids in energy conservation by removing the need to apply thrust at berth and applying a convenient solution for mooring and passenger movement, thus minimising deck crew and time at berth.

Proven electronics and deck equipment selection

The ferry’s navigation electronics suite is similar to what is found on the operator’s hybrid vessels. The main difference is the incorporation of Danfoss bespoke software that can control power management and thrust and manage combined system type two charging.

However, Collins said the integration of the Hydromaster electronic control with the Danfoss power management and distribution system had not been previously attempted.

“The deck equipment is fairly standard with the exception of the interface for the auto-mooring system and the anchor arrangement,” said Collins. “To keep the bow and stern faces clear to facilitate the auto-mooring arm and ramps, the anchor has been positioned on one quarter stowed inside one of the side gates and deployed from there with a removable recovery davit.”

Collins explained that it was a design challenge to fit in an anchor arrangement acceptable to class and flag given the limited deck space and the requirement for the auto-mooring and ramp system. Nevertheless, the integration was completed, and the ferry is also able to satisfy loading and transport parameters.

“This innovation enhances accessibility, reduces journey times, and increases capacity for both foot and cycle passengers,” Collins told Baird Maritime. “It also connects cyclists, who currently have to cross the river at designated pedestrian points, with major cycle paths in London without having to create tunnels or a bridge.”

"The concept of roll-on-roll-off for cyclists and walk-through for pedestrians travelling in a glass-sided cabin in relative silence is definitely different," added Symonds.

"For any seafarer used to conventional vessels, the relatively silent motion is slightly un-nerving, while the challenge of meeting the current MSN1823 code, which is not really developed for this type of electric ferry, has presented some unique design solutions for the entire vessel and systems."