John Metcalfe was CityLab’s Bay Area bureau chief, covering climate change and the science of cities.
Tens of thousands of wind turbines could dampen monster hurricanes into plain old bad storms, claim researchers.
Over the years, weather eggheads have dreamed up an arsenal of unusual weapons to fight hurricanes – seeding clouds to weaken their momentum, pumping cold ocean water to the surface to starve them of energy. The U.S. government has even taken the time to explain why it's "not a good idea" to blow up hurricanes with nuclear bombs (turns out there are multiple reasons!).
But here's one more possible way to attack the next Katrina: How about we wall off parts of the coastline with wind farms, which would then drain energy from these monster storm systems as they move through miles of spinning blades?
It's not as ridiculous a theory as you might imagine, at least according to the Stanford and University of Delaware researchers proposing it. They believe that platoons of oceanic wind turbines could diminish wind speeds and wave heights, as well as lower the kind of tidal surges that preceded the ultra-destructive Typhoon Haiyan. As one of them asserts: "The little turbines can fight back the beast."
The team came to this conclusion using a climate model to simulate how hurricanes Katrina, Sandy, and Isaac would move through vast fields of tens of thousands of turbines. They found that the machines would parasitically suck energy from the hurricanes' edge, causing a chain reaction in which slower winds would circle toward the storm's eye. This process hinted at major decreases in wind speed – a drop of 87 mph for Sandy, 92 mph for Katrina – and a 34 and 79 percent reduction in flooding for both storms, respectively.
Deploying armies of turbines that would be much larger than any wind farm existing today would be expensive. But unlike the cheaper option of building seawalls to mitigate flooding, the researchers say, the farms would help minimize wind damage and provide additional green benefits like reducing society's fossil-fuel dependence. And best of all is that the turbines supposedly could keep doing their energy-producing work even as a hurricane mowed over them:
While the wind farms would not completely dissipate a hurricane, the milder winds would also prevent the turbines from being damaged. Turbines are designed to keep spinning up to a certain wind speed, above which the blades lock and feather into a protective position. The study showed that wind farms would slow wind speeds so that they would not reach that threshold.
The study suggests that offshore wind farms would serve two important purposes: prevent significant damage to cities during hurricanes and produce clean energy year-round in normal conditions as well as hurricane-like conditions. This makes offshore wind farms an alternative protective measure to seawalls, which only serve one purpose and do not generate energy.