Featured Research

from universities, journals, and other organizations

Wind turbines: In the wake of the wind

Date:
April 27, 2011
Source:
DOE/Lawrence Livermore National Laboratory
Summary:
Wind turbines not only produce power, they produce wakes -- similar to what forms in bodies of water -- that are invisible ripples and waves and other disturbances in the atmosphere downstream that can damage turbines and decrease efficiency. Researchers are launching a study of those wakes, with an eye toward improving the efficiency of wind farms.

Normally invisible, wind wakes take shape in the clouds behind the Horns Rev offshore wind farm west of Denmark.
Credit: Photo courtesy of Vattenfall

On the Front Range within the Rocky Mountains, prevailing winds sweep eastward over the mountains smack into the National Wind Technology Center. Several wind turbines, some taller than a 40-story building, spin and hum at the site, just outside of Boulder, Colo., waiting for an experiment to start in the next month.

The turbines not only produce power, they produce wakes -- similar to what forms in bodies of water -- that are invisible ripples and waves and other disturbances in the atmosphere downstream that can damage turbines and decrease efficiency. Lawrence Livermore National Laboratory researchers and collaborators will launch a study of those wakes this month, with an eye toward improving the efficiency of wind farms.

The scientists also will collect valuable data that will help validate the wind flow models developed at Livermore and other laboratories and universities.

"This study is part of a larger suite of observational and model development efforts under way at LLNL to help attain aggressive state and national targets for renewable energy deployment," said Jeff Mirocha of LLNL. "This field campaign dovetails with ongoing observational studies at our Site 300 that are focused on understanding the complex wind patterns occurring in hilly, coastally influenced locations, which is similar to much of California's wind resource."

Livermore is working with the University of Colorado, National Oceanic and Atmospheric Administration (NOAA) and the National Renewable Energy Laboratory (NREL).

The Laboratory also has been working on numerical weather prediction models to predict power generated by the wind, so that wind farms can operate more efficiently while providing more power to the nation's hungry power grids. Predictive time frames range from an hour ahead to days ahead of time.

The new project entails experiments that will help make a detailed study of wakes created by wind turbines. Those profiles could help turbine and wind farm developers improve layout and design. "The wakes can damage turbines and affect turbine efficiency," said Julie Lundquist, a University of Colorado assistant professor who helped develop the models while at LLNL.

The study is aimed at an improved understanding and characterization of inflow conditions on turbines in complex terrain that would help engineers better understand, model, and design for turbine loading, turbine performance and power plant performance. The goal is to integrate advanced observational capabilities with innovative approaches to atmospheric simulation.

Researchers will collect meteorological data for validation of turbine wake models in a range of atmospheric stability conditions, including wind speed, wind direction and streamwise variance profiles.

Bob Banta, atmospheric scientist with NOAA's Earth System Research Laboratory, has spent the last several years using a sophisticated instrument -- a high-resolution, scanning dopplar lidar -- to make three-dimensional portraits of wind speeds and directions in the atmosphere. For the wind technology site project, the research team aims to capture turbulence and other wake effects in a broad wedge of air up to 7 km (4.3 miles) long and 1 km (3,280 feet) high.

The team will use the scanning lidar to make a detailed look at the atmosphere in front of and behind one of the large turbines on the NREL site: a 2.3-megawatt tower that stretches 100 m (328 ft) high to the central hub and 145 m (492 feet) to the top of a blade.

The researchers hope to capture the effects of ramp up and ramp down events, when winds suddenly gust high or die down, and they will gather data on what happens downstream when winds shift direction quickly.

"This generation of wind turbines is stretching up into a complicated part of the atmosphere," Lundquist said. "If we can understand how gusts and rapid changes in wind direction affect turbine operations and how turbine wakes behave, we can improve design standards, increase efficiency, and reduce the cost of energy,"

According to the American Wind Energy Associations, wind energy made up 2.3 percent of U.S. electricity by the end of 2010, up from 1.8 percent a year ago. Researchers have argued that to attain the Department of Energy goal of "20 percent by 2030," the turbulent lower atmosphere -- and its effects on turbines and turbine arrays -- must be better understood.

Members of the Turbine Wake and Inflow Case study include: Banta and Yelena Pichugina of NOAA; Lundquist of the University of Colorado at Boulder and NREL's National Wind Technology Center; Jeff Mirocha of LLNL; Matthew Aitken, Michael Rhodes, Brian Vanderwende, Robert Marshall, University of Colorado at Boulder graduate students; and Neil Kelley and Andrew Clifton of NREL's National Wind Technology Center.


Story Source:

The above story is based on materials provided by DOE/Lawrence Livermore National Laboratory. Note: Materials may be edited for content and length.


Cite This Page:

DOE/Lawrence Livermore National Laboratory. "Wind turbines: In the wake of the wind." ScienceDaily. ScienceDaily, 27 April 2011. <www.sciencedaily.com/releases/2011/04/110426151040.htm>.
DOE/Lawrence Livermore National Laboratory. (2011, April 27). Wind turbines: In the wake of the wind. ScienceDaily. Retrieved April 16, 2014 from www.sciencedaily.com/releases/2011/04/110426151040.htm
DOE/Lawrence Livermore National Laboratory. "Wind turbines: In the wake of the wind." ScienceDaily. www.sciencedaily.com/releases/2011/04/110426151040.htm (accessed April 16, 2014).

Share This



More Matter & Energy News

Wednesday, April 16, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Google Patents Contact Lens Cameras; Internet Is Wary

Google Patents Contact Lens Cameras; Internet Is Wary

Newsy (Apr. 15, 2014) Google has filed for a patent to develop contact lenses capable of taking photos. The company describes possible benefits to blind people. Video provided by Newsy
Powered by NewsLook.com
The Walking, Talking Oil-Drigging Rig

The Walking, Talking Oil-Drigging Rig

Reuters - Business Video Online (Apr. 15, 2014) Pennsylvania-based Schramm is incorporating modern technology in its next generation oil-drigging rigs, making them smaller, safer and smarter. Ernest Scheyder reports. Video provided by Reuters
Powered by NewsLook.com
Dutch Highway Introduces Glow-In-The-Dark Paint

Dutch Highway Introduces Glow-In-The-Dark Paint

Newsy (Apr. 14, 2014) A Dutch highway has become the first lit by glow-in-the-dark paint — a project aimed at reducing street light use. Video provided by Newsy
Powered by NewsLook.com
Google Buys Drone Maker, Hopes to Connect Rural World

Google Buys Drone Maker, Hopes to Connect Rural World

Newsy (Apr. 14, 2014) Formerly courted by Facebook, Titan Aerospace will become a part of Google's quest to blanket the world in Internet connectivity. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins