A skipper hoping to become the first to circumnavigate the globe using solar power said his catamaran could carve a wake for pollution-free shipping as he unveiled the world's largest solar-powered vessel in Germany.

Raphael Domjan, 38, pulled the covers off the 18 million euro ($27.4 million) catamaran yesterday.

"This is a unique feeling to see in front of me today a boat which I so often dreamed about," he said.

PlanetSolar, a 31 x 15-metre white catamaran, has been designed to reach a top speed of around 15 knots, equivalent to 27 kilometres per hour, and can hold up to 50 passengers.

Five hundred square metres of black solar panels top the vessel, with a bright white cockpit sticking up in the centre.

Built at the Knierim Yacht Club in Kiel in northern Germany, its state-of-the-art design also means it will be able to slice smoothly through the waves even in choppy waters.

The team behind its construction acknowledge that solar power is not about to become the main power source on modern cargo ships.

They say they want to use the voyage primarily to promote solar power and other non-polluting sources of energy and to show what can be done.

"The aim is really to show that we have the technology today, not tomorrow," Mr Domjan said.

"It's not in a laboratory or DIY. It is a technology that is reliable, able to perform and economically interesting."

PlanetSolar will launch in late March before starring at Hamburg port's 821st anniversary celebrations in May and undergoing testing between June and September.

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