Seven Questions to Understand the Sakiyama 2MW Floating Offshore Wind Turbine

• Q1. What is the scale of the wind turbine?

It uses a 2,000kW wind turbine that is commonly used for onshore wind farms in Japan.

• Q2. What is the hybrid spar type?

It is a kind of floating structure built with state-of-the-art technology developed in Japan. By using a combination of steel and concrete (steel in the upper part and concrete in the lower part) for the elongated spar-type floating body, the wind turbine’s center of gravity is lowered, resulting in improved stability. This combination also results in significant cost reduction through the use of purely domestic concrete.

• Q3. How much does one wind turbine weigh in tons?

It weighs about 3,400 tons, including ballast. It keeps its balance by loading ballast* of about 1,400 tons into the inner space of the hollow lower spar.

*Ballast is material to add weight to stabilize a floating body. In this case, it is water and crushed stone.

• Q4. Is there any possibility that the wind turbine might fall over?

It is designed to pick itself up and return to the original position no matter how much it tilts, just like a roly-poly toy.

• Q5. How do you prepare for a typhoon?

If the wind speed exceeds a predetermined level during a typhoon, the angle of the blades is turned to a feathered position where the blades are parallel to the airflow to neutralize the force of the wind.

• Q6. How many households can this wind turbine supply with electricity?

It is a 2,000kW-class wind turbine and can supply about 1,800～2,000 households.

• Q7. How is the generated electricity used?

The wind turbines are connected to Kyushu Electric Power’s grid to supply the generated electricity to the residents of the Goto Islands, including Fukue island.