If the going gets tough for the 22 oarsmen propelling the rowboat Gloriana down the River Thames during the Queen`s Diamond Jubilee pageant on 3 June, they will be able to call on some assistance in the form of two UK-built DC electric motors driving a pair of propellers.
Hidden inside the 28.6m-long barge – built for the Diamond Jubilee pageant at a cost of £1m – will be an electric drive system consisting of the two 14kW, 48V motors, a throttle system and a display, all supplied by the Devon-based motor manufacturer, LMC.
The pancake-style motors have been installed to help the rowbarge to manoeuvre in and out of its moorings and, if needed, to combat strong currents. Operating at 7–8kW and driving the propellers at just under 1,000 rpm via a 2:1 reduction system, they can propel the craft at about 8 knots. The motors can also operate in a regenerative mode, which will usually be used to harness the flow of the river to charge the vessel’s batteries while it is moored.
The Gloriana will lead a flotilla of more than 1,000 boats, carrying more than 20,000 people – including the Queen and Prince Philip – that will sail down the River Thames on 3 June to mark her Diamond Jubilee.
The vessel, built by boat-builder Mark Edwards, is the result of a project by Lord Sterling, who wanted to create a floating tribute to the Queen using sweet chestnut from Prince Charles’ private estate. It was named by the Queen when she visited Greenwich recently to unveil the restored Cutty Sark. The project was overseen by Byrne Longshore & Co, a maritime cost engineering and project management company.
The quiet, lightweight LMC motors operate with an efficiency of more than 90%. “It was important for this prestigious royal project that the motors were British-made, clean, green and economic. We were pleased to be given the opportunity to come up with a bespoke marine drive system that covered all these requirements,” says LMC’s managing director, Trevor Lees (shown above, at work on the Gloriana).
"We have been witnessing a growing trend in the boating industry for electric motors, whether it’s to provide primary power to sailboats, yachts, canal cruisers or in-shore motorboats, or even assist classic rowbarges and boats with additional power, such as the Gloriana," he adds.
Previous marine applications for the motors include a high-speed French sailboat and a zero-emission racing sailboat built recently in New Zealand. LMC also supplies motors for industrial applications. Its clients include the UK Ministry of Defence, Disney World, The Creature Technology Company, vonRoll infratec and Quantya AG.