The new system, the HTW5.2-136, is scheduled to start a trial run in October onshore at the Fukashiba Wind Power Station in Kashim-aport of Hitachi Wind Power.

Hitachi Wind Power plans to release the new system in fiscal 2017, if the test run proves to be successful.

The company has increased the rated power of the HTW5.2-136 system to 5.2MW by optimizing its setup and its control programs.

The rotor diameter in the new system has been increased to 136 m in order to raise the output in light-wind regions that have an annual average wind speed below 7.5 m/s.

In the coming years, Hitachi plans to market the system for use in light-wind regions along the coasts of Honshu, the main island of Japan.

Besides, the firm has increased the rated power of its previous model the HTW5.0-126 to 5.2MW and will be released as the HTW5.2-127.

It intends to sell the HTW5.2-127 for use at windier sites, such as the coasts of Hokkaido, northern part of the Tohoku region on Honshu, and southern Kyushu.

Hitachi said: “As an archipelago of islands, there is also potential for Japan to make greater use of offshore wind turbine generators and take advantage of these vast areas of open sea with extensive wind resources, with minimal constraints on site availability and transportation.

“A number of these installations are currently being planned. In order to generate power more efficiently, offshore wind turbine generator systems must be both extremely reliable and have a large per-turbine output.”