Japan's ambition to lead in the development of floating wind turbines is facing stiff competition from rivals in Europe — most notably from France — as companies and governments press to lower costs and prove that the technology can rival other sources of clean energy.

At the center of Japan's effort is a demonstration project off the coast of Fukushima Prefecture. The largest floating turbine project of its kind at the moment consists of a 2-megawatt turbine, a 7-MW turbine, a substation, and a 5-MW model, which was towed into place last month and is expected to begin generating power soon.

The project, funded by Japan's Ministry of Economy, Trade and Industry, is being developed by a 10-member consortium including Mitsubishi Heavy Industries Ltd. and Hitachi Ltd. One of the goals is to show whether floating offshore wind generation can be commercially viable.