KIEL, Germany -- A German adventurer is preparing to sail the world in what he says is the world's largest solar-powered boat.

The catamaran-style yacht sporting some 5,400 square feet of solar panels was put into the water Wednesday in the northern German city of Kiel.

Skipper Raphael Domjan praised the "groundbreaking" step toward what he says will be the first ever world tour by a solar-powered boat, scheduled to start in April 2011.

In the meantime, he is planning to extensively test the boat. 

The boat, built by the Knierim Yachtbau shipyard, is nearly 102 feet long, almost 50 feet wide and stands 24-1/2 feet high. The boat was designed by Planet Solar SA of Switzerland.