Solar Sailor is making waves down under

It might be hard to compete with the spectacular sights of Sydney Harbour, but a new ferry that hit the water this month to transport tourists past the Opera House and under the famous bridge is attracting almost as much attention.

The Solar Sailor, a commercial ferry powered by solar and wind energy, is an unusual sight. It has eight movable solar wings mounted over its cabin, which can be adjusted to capture the most sun or wind, as well as solar panels at the front.

Two New South Wales universities have played a role in getting the 100-passenger vessel ready to carry passengers for the tour firm, Captain Cook Cruises, that is leasing it.

Academics from the University of Technology, Sydney, designed and built the two 40 kilowatt electric motors that power the ferry. They are the latest products of electric motor technology developed by UTS faculty of engineering researchers, in collaboration with staff from the CSIRO (Commonwealth Scientific and Industrial Research Organisation).

Peter Watterson, one of the UTS academics involved in the project, said that the main advantage of the "rare earth" permanent magnet brushless DC motors is their high efficiency (96 per cent) and low weight. At just 113 kilograms, they are a quarter of the mass of an induction electric motor of equivalent power. They are also much lighter than the diesel engines that routinely power ferries.

The solar cells, which were built by BP Solar using technology licensed by the University of New South Wales's world-leading Photovoltaics Special Research Centre, can power the craft for 30 minutes at top speed.

But Dr Watterson said that at lower speeds the capacity is greater and well suited to ferries making short runs. Power is not required at all times and the cells can be replenished while passengers embark and disembark. In full sun, the cruise speed is seven knots, and three to four in overcast conditions.

There has been considerable interest in the 21-metre catamaran in Europe, where fossil fuel-powered craft are banned from some inland lakes and waterways.

"Solar Sailor creates zero water pollution, whether under solar, wind, battery or generator power," Dr Watterson said.

The engines are also extremely quiet, as the top speed is only 900 revolutions per minute, making each slightly less noisy than a domestic washing machine.

The other attraction to ferry operators is eliminating the cost of fuel.

The manufacturers of the A$2 million (Pounds 780 million) ferry hope the large number of tourists coming to Sydney for the Olympic Games later this year will translate into orders for the vessel.

The invention, the brainchild four years ago of Solar Sailor's managing director and former general practitioner Robert Dane, won the gold medal at last year's Asian Innovation Awards and has attracted a A$1 million grant from the federal government.

Details: www.solarsailor.com.