(Press-News.org) WASHINGTON D.C., April 1, 2014 -- As wind farms grow in importance across the globe as sources of clean, renewable energy, one key consideration in their construction is their physical design -- spacing and orienting individual turbines to maximize their efficiency and minimize any "wake effects," where the swooping blades of one reduces the energy in the wind available for the following turbine.
Optimally spacing turbines allows them to capture more wind, produce more power and increase revenue for the farm. Knowing this, designers in the industry typically apply simple computer models to help determine the best arrangements of the turbines. This works well for small wind farms but becomes less precise for larger wind-farms where the wakes interact with one another and the overall effect is harder to predict.
Now a team of researchers at Johns Hopkins University (JHU) has developed a new way to study wake effects that takes into account the airflow both within and around a wind farm and challenges the conventional belief that turbines arrayed in checker board patterns produce the highest power output. Their study provides insight into factors that determine the most favorable positioning -- work described in a new paper in the Journal of Renewable and Sustainable Energy, which is produced by AIP Publishing.
This insight is important for wind project designers in the future to configure turbine farms for increased power output -- especially in places with strong prevailing winds.
"It's important to consider these configurations in test cases," said Richard Stevens, who conducted the research with Charles Meneveau and Dennice Gayme at JHU. "If turbines are built in a non-optimal arrangement, the amount of electricity produced would be less and so would the revenue of the wind farm."
How Wind Farms are Currently Designed
Many considerations go into the design of a wind farm. The most ideal turbine arrangement will differ depending on location. The specific topology of the landscape, whether hilly or flat, and the yearlong weather patterns at that site both dictate the specific designs. Political and social considerations may also factor in the choice of sites.
Common test cases to study wind-farm behavior are wind farms in which turbines are either installed in rows, which will be aligned against the prevailing winds, or in staggered, checkerboard-style blocks where each row of turbines is spaced to peek out between the gaps in the previous row.
Staggered farms are generally preferred because they harvest more energy in a smaller footprint, but what Stevens and his colleagues showed is that the checkerboard style can be improved in some cases.
Specifically, they found that better power output may be obtained through an "intermediate" staggering, where each row is imperfectly offset -- like a checkerboard that has slipped slightly out of whack.
INFORMATION:
This work was funded by the National Science Foundation (grant #CBET 1133800 and #OISE 1243482) and by a "Fellowship for Young Energy Scientists" awarded by the Foundation for Fundamental Research on Matter in the Netherlands. The work used XSEDE (NSF) and SURFsara (Netherlands) computer resources.
The article, "Large Eddy Simulation studies of the effects of alignment and wind farm length" is authored by Richard J. A. M. Stevens, Dennice F. Gayme and Charles Meneveau. It will be published in the Journal of Renewable and Sustainable Energy on April 1, 2014 (DOI: 10.1063/1.4869568). After that date, it can be accessed at: http://tinyurl.com/n9o282o
ABOUT THE JOURNAL
The Journal of Renewable and Sustainable Energy is an interdisciplinary, peer-reviewed journal produced by AIP publishing that covers all areas of renewable and sustainable energy-related fields that apply to the physical science and engineering communities. See: http://jrse.aip.org/
Wind energy: On the grid, off the checkerboard
Simulation in the 'Journal of Renewable and Sustainable Energy' provides new insight into best arrangement of wind turbines on large installations
2014-04-01
ELSE PRESS RELEASES FROM THIS DATE:
Scientists solve the riddle of zebras' stripes
2014-04-01
Why zebras have black and white stripes is a question that has intrigued scientists and spectators for centuries. A research team led by the University of California, Davis, has now examined this riddle systematically. Their answer is published April 1 in the online journal Nature Communications.
The scientists found that biting flies, including horseflies and tsetse flies, are the evolutionary driver for zebra's stripes. Experimental work had previously shown that such flies tend to avoid black-and-white striped surfaces, but many other hypotheses for zebra stripes have ...
Should family businesses always keep it in the family?
2014-04-01
Montreal, April 1, 2014 – From the Murdochs to the Hiltons, families have long sought to keep their businesses in the bloodline. But new research from Concordia University's John Molson School of Business shows that's not necessarily the best method of management.
The recent study, published in the journal Entrepreneurship Theory and Practice, shows that if the family business is part of a traditional industry built on quality and reputation, a family member would make a good CEO. But if it operates in an industry that values innovation, and the firm has to stay on the ...
The human 'hairless' gene identified: One form of baldness explained
2014-04-01
It's not a hair-brained idea: A new research report appearing in the April 2014 issue of The FASEB Journal explains why people with a rare balding condition called "atrichia with papular lesions" lose their hair, and it identifies a strategy for reversing this hair loss. Specifically the report shows for the first time that the "human hairless gene" imparts an essential role in hair biology by regulating a subset of other hair genes. This newly discovered molecular function likely explains why mutations in the hairless gene contribute to the pathogenesis of atrichia with ...
Breast milk and diet up to 2 years old: A means of preventing the risk of child obesity
2014-04-01
This news release is available in French. Many studies have focused on the influence of breast-feeding on child health. From analysis of data from the ELANCE cohort, Marie Françoise Rolland-Cachera, former researcher at Inserm and her co-workers in the Nutritional Epidemiology Research Team (EREN) have shown that breast-feeding has a protective effect on the risk of obesity at 20 years of age. Researchers also emphasise that nutritional intake at the age of 2 years are critical in providing this beneficial effect. The results of the study are published in The Journal ...
One currency, one price?
2014-04-01
Economics has a "law of one price," which states that identical goods should, in theory, sell for identical prices — or else markets will even out the differences. Empirical work on the topic, however, has produced little evidence in support of this "law," and many studies showing deviations from it.
Now a newly published paper co-authored by two MIT economists, along with a colleague from the University of Chicago, presents evidence of a strong convergence of prices within the Eurozone, the region of European countries sharing a common currency. The divergence of product ...
First evidence that very small embryonic-like stem cells
2014-04-01
New Rochelle, NY, April 1, 2014 -- Rare, very small embryonic-like stem cells (VSELs) isolated from human adult tissues could provide a new source for developing regenerative therapies to repair complex tissues damaged by disease or trauma. The ability of these most-primitive, multipotent stem cells to differentiate into bone, neurons, connective tissue, and other cell types, and the proper criteria for identifying and isolating VSELs, are described in two articles in Stem Cells and Development, a peer-reviewed journal from Mary Ann Liebert, Inc., publishers. The articles ...
Survey shows spine surgeons need to screen more patients for anxiety and depression
2014-04-01
In a report published in the April edition of the Journal of Spinal Disorders and Techniques, a Johns Hopkins team says that only 10 percent of orthopaedic surgeons and neurosurgeons follow professional guidelines recommending routine psychological screenings of patients prior to major surgery for severe back and leg pain.
The oversight, researchers say, may pose a serious risk to patients' surgical recovery. Previous reports have tied bouts of depression to longer recuperations, delayed returns to work, more postsurgical complications and failures to comply with medication ...
Overcoming structural uncertainty in computer models
2014-04-01
Philadelphia, PA--A computer model is a representation of the functional relationship between one set of parameters, which forms the model input, and a corresponding set of target parameters, which forms the model output. A true model for a particular problem can rarely be defined with certainty. The most we can do to mitigate error is to quantify the uncertainty in the model.
In a recent paper published in the SIAM/ASA Journal on Uncertainty Quantification, authors Mark Strong and Jeremy Oakley offer a method to incorporate judgments into a model about structural uncertainty ...
Want spring allergy relief? Avoid stress
2014-04-01
ARLINGTON HEIGHTS, Ill. (April 1, 2014) – Stress doesn't cause allergies, but easing your mind might mean less allergy flare-ups this spring. According to a study published in the April issue of Annals of Allergy, Asthma & Immunology, the scientific journal of the American College of Allergy, Asthma and Immunology, allergy sufferers with persistent stress experience more allergy flares.
"Stress can cause several negative effects on the body, including causing more symptoms for allergy sufferers," said allergist Amber Patterson, MD, lead study author and ACAAI member. ...
Scientists ID genes that could lead to tough, disease-resistant varieties of rice
2014-04-01
As the Earth's human population marches toward 9 billion, the need for hardy new varieties of grain crops has never been greater.
It won't be enough to yield record harvests under perfect conditions. In an era of climate change, pollution and the global spread of pathogens, these new grains must also be able to handle stress. Now, researchers at Michigan Technological University have identified a set of genes that could be key to the development of the next generation of super rice.
A meta-data analysis by biologist Ramakrishna Wusirika and PhD student Rafi Shaik has ...
LAST 30 PRESS RELEASES:
“Genetic time machine” reveals complex chimpanzee cultures
Earning money while making the power grid more stable – energy consumers have a key role in supporting grid flexibility
No ‘one size fits all’ treatment for Type 1 Diabetes, study finds
New insights into low-temperature densification of ceria-based barrier layers for solid oxide cells
AI Safety Institute launched as Korea’s AI Research Hub
Air pollution linked to longer duration of long-COVID symptoms
Soccer heading damages brain regions affected in CTE
Autism and neural dynamic range: insights into slower, more detailed processing
AI can predict study results better than human experts
Brain stimulation effectiveness tied to learning ability, not age
Making a difference: Efficient water harvesting from air possible
World’s most common heart valve disease linked to insulin resistance in large national study
Study unravels another piece of the puzzle in how cancer cells may be targeted by the immune system
Long-sought structure of powerful anticancer natural product solved by integrated approach
World’s oldest lizard wins fossil fight
Simple secret to living a longer life
Same plant, different tactic: Habitat determines response to climate
Drinking plenty of water may actually be good for you
Men at high risk of cardiovascular disease face brain health decline 10 years earlier than women
Irregular sleep-wake cycle linked to heightened risk of major cardiovascular events
Depression can cause period pain, new study suggests
Wistar Institute scientists identify important factor in neural development
New imaging platform developed by Rice researchers revolutionizes 3D visualization of cellular structures
To catch financial rats, a better mousetrap
Mapping the world's climate danger zones
Emory heart team implants new blood-pumping device for first time in U.S.
Congenital heart defects caused by problems with placenta
Schlechter named Cancer Moonshot Scholar
Two-way water transfers can ensure reliability, save money for urban and agricultural users during drought in Western U.S., new study shows
New issue of advances in dental research explores the role of women in dental, clinical, and translational research
[Press-News.org] Wind energy: On the grid, off the checkerboardSimulation in the 'Journal of Renewable and Sustainable Energy' provides new insight into best arrangement of wind turbines on large installations