The National Wind Technology Center (NWTC) at the U.S. Energy Department’s National Renewable Energy Laboratory (NREL) has begun validation work on the first water power technology ever tested in an NREL dynamometer facility.
“We are testing the StingRAY at the NWTC because the core design is similar to a wind turbine-it is direct drive, but with a very large diameter,” Columbia Power Technologies CEO Reenst Lesemann said. “The dynamometer can mimic the sea, with back-and-forth oscillation, and will put the generator through its paces to ensure it can withstand ocean forces.”
Mechanical testing of the StingRAY generator, which is as tall as a two-story building and the largest generator ever tested in an NWTC dynamometer, is now under way. Over the next few months, the unit will be connected to the NWTC’s Controllable Grid Interface for electrical performance characterization.
“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,” said Mark McDade, NWTC project manager. “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.” This land-based validation effort, which is co-sponsored by Columbia Power Technologies and the Department of Energy’s Water Power Technologies Office, will occur prior to an open-water demonstration of the system scheduled for 2017 at the U.S. Navy’s Wave Energy Test Site in Hawaii.