Columbia Power has made extensive use of modeling and stepped-scale testing in its product development efforts. Over the past nine years, we’ve conducted five tank tests and three sea trials and run thousands of hours of models on hundreds of design and hull shape variations. The result of this intensive effort is a scalable wave power system that delivers the qualities that our customers need: survivability, a competitive cost and an environmentally-friendly footprint.
The initial design and development effort was started at Oregon State University. The early design generations were linear direct-drive systems, with the first prototype tests conducted at the Hinsdale Wave Research Laboratory (HWRL) in 2004. This early testing demonstrated that a liner direct-drive permanent magnet generator (PMG) was a potentially feasible solution for converting wave power into electricity. Following refinement of the concept and licensing by Columbia Power, a 1 kW device (version 1.0) was deployed off the coast of Newport, OR in 2007.
In 2008, a 10 kW second-generation device (v2.0), with improved hydrodynamic performance, was deployed at the same location. While the test was successful, projected cost of energy and reliability considerations necessitated a departure from this design and the creation of a new proprietary concept using direct-drive rotary generators. The resulting third-generation (v3.0) concept has allowed a greater range of potential energy capture and more optimal performance, as well as lower relative capital and operating costs.
Numerically-driven hydrodynamic design optimization led to the subsequent v3.1 design, which was tested at 1:33 scale at HWRL, both as a single device and in three and five unit arrays. The v3.1 design had been optimized for manufacturability, in addition to providing a performance improvement of over 230%. In February 2011, a 1:4.5 scale v3.1 prototype was deployed for thirteen month sea trials in Puget Sound.
Following this deployment, the hydrodynamic design was further optimized (v3.2) to avoid the expense and risk of range-of-motion-limiting end stops. Nearly a thousand simulations were run and the resulting design changes reduced projected capital and operating expenses, while predicting annual energy production nearly twice that of v3.1. A smaller-scale v3.2 prototype was tested at HWRL in late 2012 to validate the design improvements.
Columbia Power is currently finalizing the StingRAY design, with planned open-ocean testing of a full-scale system in 2014-2015.