VESSEL REVIEW | Dheu – Solar electric commuter catamaran to serve India's West Bengal state

Indian state-owned shipbuilder Garden Reach Shipbuilders and Engineers has handed over a new electric catamaran ferry to the Transport Department of India's West Bengal state.

Dheu ("Wave") has an aluminium hull, an FRP superstructure, a length of 24 metres (79 feet), an air-conditioned cabin that can house 50 passengers, and a non-air-conditioned cabin with space for up to 100 people. The significant capacity allows a greater number of passengers to be transported on each trip, and having to conduct fewer sailings over time will help prolong the vessel’s service life.

Flexible propulsion arrangement to permit continuous operations

A 246kWh liquid-cooled battery drives two 50kW motors connected to propellers to deliver a top speed of 10 knots. The ferry’s catamaran design guarantees stability while the use of electric propulsion generates only minimal noise and engine vibration, thus ensuring improved comfort for all on board.

The battery can be charged via shore power connection or through a set of PV panels with a total rated output of 18 kWh mounted on the deck. A 50kW diesel generator is also fitted for use during emergencies, allowing the ferry to continue operating in the event of the battery becoming depleted.

First in a modern river commuter fleet

An energy management system helps maximise electrical power so that the motors have an adequate supply across various speed settings. One of the benefits of this feature is that it minimises the risk of overheating the battery, which could result in thermal runaway.

Dheu was built in compliance with Indian Register of Shipping class rules including its Guidelines for Battery Powered Vessels. The ferry is the first in a new series of electric vessels that are slated to replace the ageing diesel-powered boats operating on the Ganges and Bhagirathi Rivers.

The introduction of Dheu into service in West Bengal is in line with a broader initiative of the Indian government to have all vessels operating in the country’s inland waterways to be powered by environment-friendly propulsion options such as batteries and low-carbon fuels.