National Wind Technology Center tests wave energy converter

The National Wind Technology Center (NWTC) at the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL) began validation work recently on Columbia Power Technologies’ StingRAY wave energy converter.

The converter is the first water power technology ever tested in an NREL dynamometer facility and, at two stories tall, the largest generator ever tested in an NWTC dynamometer.

“Though designed to benefit the wind industry, the NWTC’s large dynamometer facility is being leveraged to help advance new ocean energy technology,” NWTC Director Daniel Laird said. “While still in the early stages of development, ocean energy is progressing rapidly. Over the coming decades, ocean energy could become a major source of electricity powering high-population-density areas near the coasts.”

The NWTC dynamometer is being used to test whether the StingRAY can withstand ocean forces, because it can mimic the ocean’s back-and-forth oscillation. Within the next few months, NWTC will test the generator’s electrical performance by connecting it to the facility’s Controllable Grid Interface.

“We have one of the only facilities in the country with a dynamometer that can apply rotational torque at the speeds and forces required while also applying non-torque loads-which are side forces that simulate the action of a rogue wave hitting a wave energy converter in the ocean,” Mark McDade, NWTC project manager, said. “This matters because the structures of these energy conversion devices must be designed to handle the side forces without damage. The work is pioneering in the field of ocean energy conversion.”

An open-water demonstration of the device is scheduled for later in the year after completion of land-based tests at the U.S. Navy’s Wave Energy Test Site in Hawaii.