Offshore wind farms could tame severe weather before they achieve land

Computer simulations by Professor Mark Z. Jacobson have proven that offshore wind farms with 1000's of wind generators might have sapped the energy of three real-existence severe weather, considerably lowering their winds and associated storm surge, and perhaps stopping vast amounts of dollars in damages.

Within the last 24 years, Mark Z. Jacobson, a professor of civil and environment engineering at Stanford, continues to be creating a complex computer model to review polluting of the environment, energy, climate and weather. A current use of the model is to simulate the introduction of severe weather. Another is to figure out how much energy wind generators can extract from global wind power.

Considering these recent model studies and as a direct consequence of severe weather Sandy and Katrina, he stated, it had been natural to question: What can happen if your hurricane experienced a sizable variety of offshore wind generators? Would the power extraction because of the storm spinning the turbines' rotor blades slow the winds and diminish the hurricane, or would the hurricane destroy the turbines?

So he worked out developing the model further and replicating what could happen if your hurricane experienced a massive wind farm stretching many miles offshore and across the coast. Amazingly, he discovered that the wind generators could disrupt a hurricane enough to lessen peak wind speeds by as much as 92 miles per hour and reduce storm surge by as much as 79 percent.

The research, carried out by Jacobson, and Cristina Archer and Willett Kempton from the College of Delaware, was released online in Character Global Warming.

The scientists simulated three severe weather: Sandy and Isaac, which struck New You are able to and New Orleans, correspondingly, this year and Katrina, which devastated New Orleans in 2005.

"We discovered that when wind generators can be found, they decelerate the outer rotation winds of the hurricane," Jacobson stated. "This feeds to decrease wave height, which reduces movement of air toward the middle of the hurricane, growing the central pressure, which slows the winds from the entire hurricane and disappears it faster."

Within the situation of Katrina, Jacobson's model says a range of 78,000 wind generators from the coast of recent Orleans might have considerably destabilized the hurricane prior to it made landfall.

Within the computer model, when Hurricane Katrina arrived at land, its simulated wind speeds had decreased by 36-44 meters per second (between 80 and 98 miles per hour) and also the storm surge had decreased by as much as 79 percent.

For Hurricane Sandy, the model forecasted a wind speed reduction by 35-39 meters per second (between 78 and 87 miles per hour) and around 34 percent reduction in storm surge.

Jacobson appreciates that, within the U . s . States, there's been political potential to deal with setting up a couple of hundred offshore wind generators, not to mention hundreds of 1000's. But he thinks you will find two financial incentives that may motivate this type of change.

The first is the decrease in hurricane damage cost. Damage from severe severe weather, triggered by high winds and storm surge-related flooding, can encounter the vast amounts of dollars. Hurricane Sandy, for example, triggered roughly $82 billion in damage across three states.

Second, Jacobson stated, the wind generators would purchase themselves in the long run by producing normal electricity yet still time reducing polluting of the environment and climatic change, and supplying energy stability.

"The turbines may also reduce damage if your hurricane comes through," Jacobson stated. "These 4 elements, each by themselves, lessen the cost to society of offshore turbines and really should be adequate to motivate their development."

An alternate arrange for safeguarding seaside metropolitan areas involves building massive seawalls. Jacobson stated that although these might stop bad weather surge, they would not impact wind speed substantially. The price of these, too, is important, with estimations running between $10 billion and $40 billion per installation.

Current turbines can withstand wind speeds as high as 112 miles per hour, which is incorporated in the selection of a category two to three hurricane, Jacobson stated. His study indicates that the existence of massive turbine arrays will probably prevent hurricane winds from reaching individuals speeds.

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Hurricanes pose risk to offshore wind farms

When an oncoming hurricane curves offshore — as most do — we usually breathe a sigh of relief. But soon, those offshore storms might give us something more to worry about.

By Heribert Proeppe, AP file

Windmills in the North Sea, off of the village of Blavandshuk near Esbjerg, Denmark.

By Heribert Proeppe, AP file

Windmills in the North Sea, off of the village of Blavandshuk near Esbjerg, Denmark.

Offshore hurricanes could demolish half the turbines in proposed wind farms just off the USA's coastlines, according to a study out Monday in the Proceedings of the National Academy of Sciences.

"We find that hurricanes pose a significant risk to wind turbines off the U.S. Gulf and East coasts, even if they are designed to the most stringent current standard," the authors from Carnegie Mellon University in Pittsburgh write.

Engineer Stephen Rose and colleagues conducted the study in response to a 2008 report from the U.S. Department of Energy, which said that wind energy should ideally provide one-fifth of all electricity in the USA by 2030. The engineers estimated that over a 20-year span many turbine towers would buckle in wind farms enduring hurricane-force winds off the coasts of four states — Massachusetts, New Jersey, North Carolina and Texas — where offshore wind-farm projects are now under consideration.

Despite their record of death and destruction in the USA, 75% of all Atlantic basin hurricanes remain offshore and do not hit land, according to Chris Landsea, science and operations officer at the National Hurricane Center in Miami.

Wind turbines are vulnerable to hurricanes because the maximum wind speeds in those storms can exceed the current design limits of wind turbines, according to the study.

Failures can include loss of blades and buckling of the supporting tower.

The research incorporated the current construction standards for the turbines, reports Rose. "Our study assumed wind turbine design for the current standards, with a maximum sustained wind speed of 111 mph near the top of the turbine, about 90 meters (about 300 feet) above the surface. This is the equivalent of a Category 3 hurricane," he says.

The study had to use computer models to simulate hurricanes' effect on the wind turbines, as no offshore wind turbines have yet been built in the USA (although there are 20 offshore wind projects in various stages of planning).

However, turbine tower buckling has occurred in typhoons in the Pacific. Hurricanes are the same type of storms as typhoons.

Of the four locations examined in the study, offshore of Galveston County, Texas, is the riskiest location to build a wind farm, followed by the Outer Banks of North Carolina, Atlantic City and Martha's Vineyard, Mass.

"Galveston was the riskiest because it gets hit by hurricanes the most frequently," says Rose.

The damage caused by Category 3, 4 and 5 hurricanes is important for offshore wind development in the USA, the study notes, because every state on the Gulf of Mexico coast and nine of the 14 states on the Atlantic Coast have been struck by a Category 3 or higher hurricane from 1856 through 2008.

"As you get to Categories 3, 4, 5 — that's where the risks are," says Rose. "The intense hurricanes pose the most risk."

However, damage could be greatly reduced by building the farms in lower-risk areas and boosting the abilities of turbines to withstand higher winds.

This would "greatly enhance the probability that offshore wind can help to meet the United States' electricity needs," according to the study.

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Offshore quake causes panic, no tsunami in Chile (AP)

SANTIAGO, Chile – A magnitude-6.2 earthquake struck Monday just off the shore of south-central Chile, the same area devastated by a massive temblor two years ago. But there were no immediate reports of damage and authorities said it would not cause a tsunami.

Monday's quake was centered 31 miles (50 kilometers) northwest of Concepcion, and relatively shallow at 12 miles (20 kilometers) deep. But Chile's navy announced that it wasn't the kind of quake to generate a deadly tsunami of the kind that ravaged nearby coastal cities when an magnitude-8.8 quake devastated Chile in 2010.

The U.S. Geological Service said this quake struck at 1:04 p.m. local time (1604 GMT) with a magnitude of 6.2. Chilean seismologists measured it as a less-powerful 5.8.

Chile's national emergency office said there were no immediate reports of injuries or damage.

Cellphone service was briefly interrupted as people tried to reach loved ones, and radio stations and social networks lit up with comments, including many who said the shaking made them panic. Light fixtures swayed in many homes, but the power remained on.

The much-stronger quake that struck on Feb. 27, 2010, killed 524 and caused 31 disappearances, wrecking 220,000 homes and leaving $30 billion in damage. The disaster agency and the navy shared the blame for a botched tsunami warning then that gave some coastal dwellers a false sense of security.

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