“Crickets”, says Dominic von Terzi, “You can’t imagine the noise they make.” He’s talking about an unexpected hurdle his team from GE’s European Research Center in Munich ran into while looking for ways to make wind farms work better and quieter.
Von Terzi leads a team of researchers from the center’s Aerodynamics & Acoustics Laboratory. They recently spent two weeks using sophisticated algorithms and software to precisely measure the noise produced by a Kansas wind farm. “Actually the loudest noise measured from this farm came from the crickets,” von Terzi says.
The crickets were so loud they forced the team to review their calculations and re-calibrate equipment to better differentiate between cricket chirping and wind turbine noise.
The European Research Centre in Munich, which opened 10 years ago this week, has developed a specialty in these field trials. They have given researchers and engineers key insights into how to build better wind farms.
Several years ago, for example, a field experiment at a wind farm in the Netherlands showed that adjusting the activity of upstream turbines could optimize and improve the performance of downstream turbines.
The result led to a radical shift in how researchers viewed wind farms. It pushed them away from “turbine centric” thinking – measuring individual wind turbines – to a more holistic “wind park” approach. “The focus has changed,” von Terzi says. “Before it was about the performance of individual wind turbines in a given location, now it is about overall farm output.”
The research has already helped GE launch two new wind farm applications. They help customers recapture lost power output caused by wakes behind wind turbines, and manage farm noise.
Von Terzi and other GE scientists are studying changes in wind flow after it passes through a wind turbine. Image credit: Graham Brooks
As turbine technology evolves, field trials are becoming more necessary and frequent, von Terzi says. New wind turbines will be equipped with software, sensors and analytics that will allow them to work better with each other and with other streams of data, like weather forecasts.
Von Terzi’s lab is working closely with Technical University of Munich, which has an academic chair in wind power engineering and regularly hosts major academic conferences on the topic. “We have done a lot of bilateral work with the university particularly in the area of algorithms,” von Terzi says. “It’s about making best use of the entire eco-system between the turbine, farm, location, grid and aspects such as weather conditions to get the best efficiencies and operational performance.“
On the Farm: GE Turbines at Tehachapi, Calif. Image credit: GE Power & Water Top image: A GE wind turbine at a wind farm outside, Izmir, Turkey
Besides Kansas, Von Terzi’s team has recently been twice to a farm in Illinois and ran tests in other parts of the US and Europe. “We will often be in a location for a few weeks or go install our equipment and look at the results remotely over a period” of time, he says.
It turns outs that crickets are not the only troublemakers. “Keeping cows fenced off from the cables, all sorts of things like this happen in the field,” von Terzi says. ”It’s all a world away from a high tech research lab.“