New Arrangement of Wind Turbines Increases Productivity by a Third

By staggering and spacing out wind turbines in offshore wind farms, engineers could improve performance by as much as a third, a new study published in Geophyiscal Research Letters found.

"Staggering every other row was amazingly efficient," said Cristina Archer, associate professor of physical ocean science and engineering and geology at the University of Delaware.

Archer and her colleagues examined an offshore wind farm near Sweden, comparing the existing grid-like layout to six alternatives. Each arrangement was simulated for several weeks using computer models that took into account the eddies the turbines create downwind as their blades spin and how that impacts surrounding turbines.

Based on the results, the researchers determined that by both spacing out and staggering the turbines, losses caused by eddies dropped and overall performance increased.

However, while the optimal configuration had the rows oriented toward the direction of the prevailing wind, the researchers noted that the prevailing winds for many places shift with the seasons. Knowing this could influence where and how future offshore wind farms are configured, Archer said.

"We want to explore all these trade-offs systematically, one by one," she explained.

Previously, Archer and her colleague Mark Jacobson of Stanford University found that turbines could power as much as half of the world's future energy demands with little environmental impact -- a discovery they made by calculating the maximum theoretical potential of wind power throughout the world. The study, published in the Proceedings of the National Academy of Sciences, examined the effects a vast number of turbines would have on surface temperatures, water vapor and atmospheric circulations, among other things.

"Wind power is very safe from the climate point of view," Archer determined.

A follow-up study looked at how worldwide wind energy varies seasonally, finding that in most regions where wind farms are most feasible, the most productive months typically fall between December and February.

Taking into account all three studies, Archer said: "I'm hoping these will be tools for giving a general overview of wind at the global scale."