It almost sounds too good to be true: Install tens of thousands of wind turbines in the Gulf of Mexico and you not only get clean electricity, you also knock out the catastrophic punch of hurricanes.
“You can dissipate hurricanes so much that you can reduce wind speeds, peak wind speeds by more than half, and the storm surge by almost 80 percent in the case of New Orleans and hurricane Katrina.”
That is according to Dr. Mark Jacobson of Stanford University. Jacobson, a Stanford University professor of civil and environmental engineering, co-authored the study with scientists from Cornell University and the University of California-Davis.
“We ran simulations without turbines present, and then with turbines present,” Jacobson says.
Their computer models focused on Hurricanes Sandy, Isaac and Katrina.
A satellite image of Katrina without wind turbines shows the storm’s impact from space.
“As it hits land it starts to dissipate, it's causing damage over land,” Jacobson says. Then he says they modified the computer model, adding 78,000 wind turbines in the Gulf of Mexico.
“We added tens of thousands of turbines in this triangular region up here,” he says, pointing to a northeastern corner of the gulf. “And you can see initially that these turbines are reducing the wind speeds significantly.”
Jacobson says his research shows the turbines could reduce the devastating power of a hurricane so much that the turbines themselves would not be damaged.
“The wind speeds are dissipated, the hurricanes are dissipated sufficiently so that you never get to the destructive wind speed of a turbine even in a hurricane such as hurricane Katrina, which destroyed much of New Orleans.”
One of the world’s largest makers of wind turbines, Siemens, says each offshore turbine can cost $2.1-million per megawatt. Thousands of them would cost tens of billions of dollars.
But Jacobson says it is an investment that pays for itself.
“You get all that money back by electricity sales over 25-30 years, and you reduce storm surge and wind speed associated with a hurricane.”
Eyewitness News asked a University of New Orleans scientist to examine the Jacobson study.
“My initial reaction,” says Dr. Ioannis Georgiou of UNO, “was, is this possible?”
Georgiou is director of the Pontchartrain Institute for Environmental Sciences and has a background in storm surge and hydrodynamic modeling.
“The assumption here is that there's a loss of kinetic energy because of the friction through the blades and the rotors and so forth. That energy has to go somewhere and it goes into electricity and heat basically.”
Georgiou says the idea obviously has benefits.
“I'm not questioning the reduction in winds.”
But Georgiou says some aspects of the research need more study.
For example, he says Louisiana's shoreline is far more complex than the research model shows.
“We don't have a straight shoreline, right. We have deltas. We have estuaries. We have levees. We have flood protection systems, layered defenses.”
Georgiou says the research doesn't fully account for the various angles of attack that storms take.
“Where its outer bands are going to be affected by the turbines may cause the storm system to be higher on the east bank of the Mississippi levees, for example, St. Bernard and so forth; and much lower on the other side.”
Georgiou cites hurricane Isaac as an example of a weaker storm that produced more storm surge than some stronger storms.
He said storm surge is not directly related to wind speed. So reducing wind speed won't have a direct effect on cutting down storm surge.
“The presence or absence of wetlands and geometry, you know, the shape of the basin also affect, locally, storm surge quite a bit.
Ioannis Georgiou says he believes it is going to take quite a bit more study before a huge investment can be made in the kind of concept that the Jacobson study proposes.