Wave Energy Research and Development at JAMSTEC

Offshore Floating Wave Energy Device Mighty Whale

Wave energy is an indirect and condensed form of solar energy. Over the past few decades considerable progress has been made worldwide, through research and developmental work on conversion technologies.

Developments in Japan began with Yoshio Masuda's experiments in the 1940's. Since 1987, the focus has been on a floating device named Mighty Whale. Projected applications for a row of such devices include energy supply to fish farms in the calm waters behind the devices, and aeration/purification of seawater. The picture below shows an artist's impression of the proposed applications for the Mighty Whale system.

The prototype dimensions were chosen to be 50 m (Length) X 30 m (Breadth) X 12 m (Depth). The design called for it to float at even keel at a draft of 8 m. The overall rated power capacity was set at 110 kW.

The operating water depth at the test site is 40 m, and the prototype is to be moored facing the predominant wave direction as illustrated below. The prototype contains three air chambers that convert wave energy into pneumatic energy. Wave action causes the internal water level in each chamber to rise and fall, forcing a bi-directional airflow over an air turbine. B1b3_d2.1

The turbines drive three induction generators to produce 3-phase AC output at 200 Volts.

Three buoyancy chambers are provided directly behind the air chambers, two each along the device sides, and three in the aft-most region. Two vertical fins near the two aft corners provide lateral stability to the device. In the forward central buoyancy chamber is housed a Control Cabin which serves as an onboard Measurement Station. This space also contains the control system for the air turbines and generators.

For further information on Mighty Whale contact Project Director

Yukihisa Washio, Marine Technology Department, JAMSTEC, 2-15 Natsushima-cho, Yokosuka, Japan, 237

Tel: +81-468-67-5576, Fax: +81-468-66-5746

E-mail: washioy@jamstec.go.jp