|Incidents at Wilton Wind Farm Concern Some Residents | Video|
May 2, 2011
|Those who live by a wind farm near Wilton are concerned about safety. A blade on a turbine broke in heavy wind over the weekend.
Residents say a string of recent incidents show something needs to be done, but state leaders say they are safe.
A similar incident occurred earlier this year near Minot and a few months ago, the entire nose of a turbine fell to the ground near Rugby.
The fiberglass on this wind turbine blade near Wilton peeled away like a banana in the middle, and residents who live near the wind farm are concerned.
Wilton resident James Theurer said: "I would be worried to send my kids up anywhere around on there. I mean, even up onto the roads. The towers are close enough to the roads that if they`re up there doing something that something could happen, in the winter, the ice (could) fly off and hit one of them or, you know, even for their safety out here in the yard."
Some say a bigger buffer zone is needed between wind farms and homes. They say the broken blade is proof that turbine failures occur and the risks are too great to place these structures only a third of a mile from homes.
But public service commissioners say neighbors are safe, because the farthest the blades would fly if they`re spinning as fast as they could, would be about 200 feet, which they say is well short of the required buffer zone.
"We go to great care to make sure that the distance between a turbine and an occupied dwelling is safe under the worst case scenario. I think Burleigh County has certainly done the same thing with their ordinance," said Public Service Commissioner Kevin Cramer.
Residents say natural disasters, like tornadoes, are always on their minds.
Cramer said: "You can`t guard against every eventuality. If something like a tornado was to come through, of course, and hit any infrastructure, with the velocity and the speed with which it throws things around, it doesn`t matter if it`s a barn or a grain elevator, or a wind turbine, there are just some things you can`t guard against."
Residents say living next to a wind farm is not pleasant.
"I wouldn`t buy another piece of property like this, this close to the towers," said Theurer.
Cramer says the exact cause of the Wilton blade`s break is unknown, but he points out that a Grand Forks company manufactures the blades, and he says there have been similar problems in other states with the same blades.
Turbulent Wind Turbine Wakes Studied
by Caleb Denison, May 2nd, 2011
Much like the jet engines of a commercial airliner leave “jet wash” in their wake, wind turbines also disturb the air behind them as they spin, if to a lesser degree. This effect is the focus of a study called the Turbine Wake and Inflow Characterization Study (TWICS). The study is led by Julie Lundquist, assistant professor in the atmospheric and oceanic sciences department at the University of Colorado Boulder, and involves researchers from the National Oceanic and Atmospheric Administration (NOAA), the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL), and the Lawrence Livermore National Laboratory (LNLL) in Livermore, Calif.
In a statement, Lundquist points out that the turbines used in today’s massive wind farm projects stretch up into a complicated part of the atmosphere. Apparently, the wakes they create at these heights could affect the atmosphere and influence other wind turbines downstream, possibly causing damage and decreasing efficiency. As part of the study, the team intends to perform experiments that will help make a detailed study of wakes created by wind turbines. The hope is that these profiles could answer questions about how gusts and rapid changes in wind direction affect turbine operations and help turbine and wind farm developers improve layout and design.
The researchers will use several methods to study the wakes and develop these profiles. One of the methods will involve using an instrument developed at NOAA called a high-resolution scanning Doppler lidar which will monitor a wind turbine at NREL’s National Wind Technology Center in south Boulder. According to LLNL, the lidar “produces three-dimensional portraits of atmospheric activity and can capture a wedge of air up to 3,280 feet from the ground and 4.3 miles long. Robert Banta, an atmospheric scientist with NOAA’s Earth System Research Laboratory has worked with the instrument and said that, while the wake effect has been studied in wind tunnels and other models, the atmosphere is very different because it is more complicated and variable.
The study will also use a specialized laser called a Windcube lidar and a sonic detection and ranging system, called a Triton sodar, to measure wind and turbulence. What’s more, NREL installed two 135 meter (about 442 ft.) tall meteorological towers to measure air temperature and provide even more wind and turbulence data.