PGE to perform telemetry study at Willamette Falls
In the spring and summer of 2009, Portland General Electric (PGE) plans to implement a telemetry study at its 16.8-MW Willamette Falls project in Oregon. The goal of this study is to evaluate lamprey passage at the project as a result of several recent modifications to the fish passage structures, says Tim Shibahara, fish biologist with Portland General Electric.
The 2009 telemetry study will characterize lamprey passage at the project, including recent modifications to the flow control structure and the north fish bypass, Shibahara says. The study also will focus on the performance of the several recently installed lamprey passage structures and aid in continuing to investigate opportunities for improvements. Shibahara says results of the study will provide passage efficiency and timing data.
During the 2008 lamprey passage season, PGE initiated construction of several significant structures on the concrete cap that sits on top of Willamette Falls, on the Willamette River, to improve passage of Pacific lamprey, Shibahara says. This work included:
– Construction of three lamprey ramps. Personnel verified successful upstream passage of Pacific lamprey using these ramps;
– Modification of a once defunct fishway to provide lamprey passage. Again, successful upstream passage was verified; and
– Minor modifications to improve lamprey passage within the fish ladder. These changes primarily addressed migration barriers posed by bulkhead slots.
The need for the above changes was identified from research performed to satisfy the conditions of the project’s Federal Energy Regulatory Commission new license (relicense), issued in 2005. The research showed that only 35 percent of the Pacific lamprey studied passed the Willamette Falls project in 2005, Shibahara says. In contrast, more than 90 percent of radio-tagged fish returned to the project each year. These numbers led PGE to the conclusion that passage of upstream migrating Pacific lampreys at the project was relatively low.
EPRI continues development of fish-friendly turbine runner
EPRI is continuing development of its Alden/Concepts NREC turbine. The next phase of research on this technology will entail producing an engineering design, fabricating a physical turbine model, and testing the model, EPRI says.
Funding for this research comes from an award from the U.S. Department of Energy (DOE) for research and development of advanced water power projects. The DOE award requires a minimum 50 percent industry funding match.
EPRI began development work on this new turbine in 1996. The goal was to develop a turbine that is more than 90 percent efficient and allows fish to pass with a mortality rate of 5 percent or less. The Alden/Concepts NREC turbine features a helix-shaped runner with only three blades. Pilot-scale tests have demonstrated mortality levels below the 5 percent goal for many fish species.
Voith Hydro will produce a preliminary engineering design for the turbine. This includes design of the spiral case, stay vanes, head cover, gate system, bearings, and seals. All major components will undergo stress/strain checks to validate the design. Then Voith Hydro will design and fabricate a physical model for performance testing. Testing will measure turbine efficiency, cavitation inception, power, pressure pulsation, gate torques, axial thrust, and runaway speed. Results of these analyses will support refinement of the design and assessment of its performance relative to traditional hydro turbine designs. All of these tasks are scheduled to be complete in 2009.
Brookfield Renewable Power is interested in testing the new turbine at its 49.8-MW School Street project on the Mohawk River in New York. In February 2007, the Federal Energy Regulatory Commission granted Brookfield a license to test the advanced turbine-generator at the project.