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.
Normally invisible, wind wakes take shape in the clouds behind the Horns Rev offshore wind farm west of Denmark. Photo courtesy of Vattenfall.
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.
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.
Anne Stark | EurekAlert!
Perovskite-silicon solar cell research collaboration hits 25.2% efficiency
15.06.2018 | Helmholtz-Zentrum Berlin für Materialien und Energie GmbH
Second heat source optimises heat pump system
12.06.2018 | FIZ Karlsruhe – Leibniz-Institut für Informationsinfrastruktur GmbH
Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.
Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...
The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.
Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.
An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.
Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...
Light detection and control lies at the heart of many modern device applications, such as smartphone cameras. Using graphene as a light-sensitive material for...
Water molecules exist in two different forms with almost identical physical properties. For the first time, researchers have succeeded in separating the two forms to show that they can exhibit different chemical reactivities. These results were reported by researchers from the University of Basel and their colleagues in Hamburg in the scientific journal Nature Communications.
From a chemical perspective, water is a molecule in which a single oxygen atom is linked to two hydrogen atoms. It is less well known that water exists in two...
13.06.2018 | Event News
08.06.2018 | Event News
05.06.2018 | Event News
15.06.2018 | Materials Sciences
15.06.2018 | Ecology, The Environment and Conservation
15.06.2018 | Power and Electrical Engineering