U.S. Department of Energy and SWAY Collaborate on Offshore Wind Demonstration Project

This is an excerpt from the Third Quarter 2012 edition of the Wind Program R&D Newsletter.

The U.S. Department of Energy's (DOE's) National Renewable Energy Laboratory (NREL) is collaborating with SWAY, a renewable energy company from Norway, on an offshore wind energy demonstration project deployed off the coast of Bergen, Norway. The project provides DOE and NREL with a unique opportunity to study one of the world's first floating wind turbines to be deployed and enhances SWAY's data collection program. SWAY hopes these data will validate its design for a 10-megawatt floating offshore wind turbine.

The SWAY one-fifth scale prototype has a 13-meter (m) downwind rotor on a 29-m tower, with a large portion of the tower beneath the ocean surface. The tower and turbine rotate together on the mooring and are designed to swivel according to wind direction. A downwind rotor allows the tower to have support cables on the upwind side, reducing the structural requirements on the tower and saving weight and costs.

In June, NREL installed scientific equipment on the seabed and on the prototype above the water line to collect data that will help validate a computer model of the SWAY design. The equipment will provide NREL researchers with practical experience on testing floating offshore wind systems, and the data gathered from this project will accelerate the development of offshore wind design tools and models.

The instruments on the seabed will collect information such as wave height and direction, tidal variations, and sea temperatures. Instrumentation installed on the turbine prototype above the water will collect atmospheric data such as wind speed and direction and operational data such as platform motions, loads, and performance.

Since its commissioning on June 23, 2012, the equipment has been collecting data around the clock at a rate of 1.5 gigabytes per day. NREL researchers hope to continue collecting data for 6 months to a year. NREL will then remove the equipment, analyze the data, and publish a report on the findings.