Study: Offshore wind turbines can weaken hurricanes (video)

HOUSTON — Offshore wind turbines could help prevent destruction caused by hurricanes by draining the storms of their deadly winds before they made landfall, according to a new scientific study.

The study, published Wednesday in the journal Nature Climate Change, estimates that a massive field of wind turbines could slow hurricane wind speeds by as much as 92 miles per hour and reduce storm surges by 79 percent in some situations.

Stanford University professor Mark Z. Jacobson, one of the report’s three authors, said the study marks the first time researchers have identified the potential hurricane-weakening effect of offshore wind turbines.

“If people are on the edge of whether they want to do offshore wind in the East Coast or Gulf Coast, I think this should be an additional motivation for doing it,” Jacobson said.

Jacobson and his team conducted the study by using computer models that simulated some of the most devastating and well-known storms in recent years, including 2012’s Hurricane Isaac and Hurricane Sandy and 2005’s Hurricane Katrina. They combined that with models of how wind turbines interact with the environment and simulated what would have happened if massive numbers of turbines were put in the way of those storms.

The result: The storms were largely depleted of their destructive forces by the time they hit land.

The turbines aren’t destroyed by the hurricanes because they slow a hurricane’s outer wall winds before those winds can fuel the creation of a devastatingly powerful eye.

Ordinarily, big ocean waves help power the hurricane, because the friction they create helps decrease the storm’s central air pressure. When turbines are present, their blades’ resistance slows the speed of the storm’s outer winds, which in turn reduces the height of the waves and increases the storm’s central air pressure.

The implications of Jacobson’s find could be big. Wind advocates have long touted the environmental benefits of the technology, and the potential for turbines to help prevent storms could further their argument.

“I think cities in risky areas would want to consider this,” Jacobson said. “It can serve duel benefits. It can generate electricity, and it can provide some storm impact reduction.”

For now, it’s unlikely the conditions Jacobson put into his simulation — an array of at least 78,000 wind turbines — could be replicated in reality, given the vast price of such an endeavor. The $3 billion London Array, located about 12 miles off the coast of Great Britain, is the world’s largest offshore wind farm with 175 turbines.

But, Jacobson says, the alternative isn’t cheap either: Hurricane Sandy caused an estimated $82 billion in damage in three states.

Moreover, in the wake of Hurricane Sandy, state and local officials in coastal areas have taken a renewed interest in developing infrastructure designed to increase their communities’ resiliency from natural disasters.

Last year, then-New York City Mayor Michael Bloomberg proposed a system of levees, flood walls and other infrastructure that could protect the city from major storms and the effects of climate change. But it carried a hefty price tag too, at an estimated $20 billion.

Jacobson said hurricanes could likely be weakened by vastly fewer than 78,000 turbines, and he’s working to figure out exactly how many could be needed to protect different parts of the country.

He also says that unlike a seawall, turbines can help pay for themselves by generating power. “Every turbine you add extracts energy (from the hurricane),” Jacobson said. “You’ll get a benefit from any number of turbines.”