Two super-sized coils. Each made of about 200 pounds of copper and carrying electricity in five-foot square frames. (see photo, right)
With the flip of a switch, this test device at the Pacific Northwest National Laboratory in Sequim, Wash., creates a magnetic field that mimics the one generated by wave and hydrokinetic energy devices companies are hoping to use to harness power from oceans and rivers in the Northwest.
Scientists want to know if that electromagnetic field will affect marine and estuarine animal behavior, including migration, finding food and avoiding predators.
Aquatic animals such as sharks, skates, salmon, sea turtles and lobsters may use the Earth’s natural magnetic fields like a compass to navigate and find food. Will undersea power transmission weaken their survival skills?
To find out, researchers place aquariums filled with sea creatures near the two copper coils and activate the electromagnetic field at various strengths to test the animals’ reactions. Does the field interfere with juvenile coho salmon’s ability to recognize and avoid predators? Does it change the typically fast, flicking movements of Dungeness crab’s odor-detecting mini-antennae? Does it attract or repel the marine life?
“The ocean’s natural ebb and flow can be an abundant, constant energy source,” said PNNL oceanographer Andrea Copping, who is the principal investigator on the project out of the Sequim Marine Sciences Laboratory. “But before we can place power devices in the water, we need to know how they might impact the marine environment.”
PNNL marine ecologist Jeff Ward will discuss this research Wednesday at Oceans 2010, an ocean engineering conference that runs through Thursday in Seattle.
“We really don’t know if the animals will be affected or not,” Ward said. “There’s surprisingly little comprehensive research to say for sure.”
There have been some limited studies in this area, according to PNNL, but most have been conducted outside the United States and involved animals that aren’t common in U.S. waters.
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Ward noted this project will help develop a broader body of information from which scientists, marine power developers and the regulatory agencies that permit the power devices can draw to determine how proposed devices could affect certain marine life at a given site.
If animals demonstrate a noticeable behavior change in the controlled environment of laboratory tests, PNNL researchers may conduct a field study with test animals placed near pilot marine power devices such as the one Snohomish County PUD has proposed for Admiralty Inlet in Washington state’s Puget Sound.
As part of the project, scientists at Oak Ridge National Laboratory are also examining how electromagnetic fields created by hydrokinetic devices, which generate power from free-flowing water in rivers and streams, might affect freshwater animals. And researchers from Northwest National Marine Renewable Energy Center at Oregon State University are also studying the potential electromagnetic effects on crabs.
This study is a component of PNNL’s larger research effort to better understand the potential environmental impact of marine and hydrokinetic energy development. PNNL researchers are also examining whether underwater noise from these devices could impact aquatic life, whether underwater animals could be injured by the rotating turbines in tidal power devices and how marine devices could impact the flow patterns of coastal waters. All the work is being funded by DOE’s Office of Energy Efficiency & Renewable Energy, Wind and Water Power Program.