From the University of Delaware a press release I just can’t stop laughing about. Of course, they have no real-world tests of this claim, only “their sophisticated climate-weather model”. No numbers were given on turbine “mortality”, so one wonders how many would survive.
Offshore wind turbines could weaken hurricanes, reduce storm surge
Wind turbines placed in the ocean to generate electricity may have another major benefit: weakening hurricanes before the storms make landfall.
New research by the University of Delaware and Stanford University shows that an army of offshore wind turbines could reduce hurricanes’ wind speeds, wave heights and flood-causing storm surge.
The findings, published online this week in Nature Climate Change, demonstrate for the first time that wind turbines can buffer damage to coastal cities during hurricanes.
“The little turbines can fight back the beast,” said study co-author Cristina Archer, associate professor in the University of Delaware’s College of Earth, Ocean, and Environment.
Archer and Stanford’s Mark Jacobson previously calculated the global potential for wind power, taking into account that as turbines are generating electricity, they are also siphoning off some energy from the atmosphere. They found that there is more than enough wind to support worldwide energy demands with a negligible effect on the overall climate.
In the new study, the researchers took a closer look at how the turbines’ wind extraction might affect hurricanes. Unlike normal weather patterns that make up global climate over the long term, hurricanes are unusual, isolated events that behave very differently. Thus, the authors hypothesized that a hurricane might be more affected by wind turbines than are normal winds.
“Hurricanes are a different animal,” Archer said.
Using their sophisticated climate-weather model, the researchers simulated hurricanes Katrina, Isaac and Sandy to examine what would happen if large wind farms, with tens of thousands of turbines, had been in the storms’ paths.
They found that, as the hurricane approached, the wind farm would remove energy from the storm’s edge and slow down the fast-moving winds. The lower wind speeds at the hurricane’s perimeter would gradually trickle inwards toward the eye of the storm. “There is a feedback into the hurricane that is really fascinating to examine,” said Archer, an expert in both meteorology and engineering.
The highest reductions in wind speed were by up to 87 mph for Hurricane Sandy and 92 mph for Hurricane Katrina.
According to the computer model, the reduced winds would in turn lower the height of ocean waves, reducing the winds that push water toward the coast as storm surge. The wind farm decreased storm surge — a key cause of hurricane flooding — by up to 34 percent for Hurricane Sandy and 79 percent for Hurricane Katrina.
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 alterative protective measure to seawalls, which only serve one purpose and do not generate energy.
Jacobson and study co-author Willett Kempton, professor in UD’s College of Earth, Ocean and Environment, weighed the costs and benefits of offshore wind farms as storm protection.
The net cost of offshore wind farms was found to be less than the net cost of generating electricity with fossil fuels. The calculations take into account savings from avoiding costs related to health issues, climate change and hurricane damage, and assume a mature offshore wind industry. In initial costs, it would be less expensive to build seawalls, but those would not reduce wind damage, would not produce electricity and would not avoid those other costs — thus the net cost of offshore wind would be less.
The study used very large wind farms, with tens of thousands of turbines, much larger than commercial wind farms today. However, sensitivity tests suggested benefits even for smaller numbers of turbines.
“This is a paradigm shift,” Kempton said. “We always think about hurricanes and wind turbines as incompatible. But we find that in large arrays, wind turbines have some ability to protect both themselves and coastal communities, from the strongest winds.”
“This is a totally different way to think about the interaction of the atmosphere and wind turbines,” Archer said. “We could actually take advantage of these interactions to protect coastal communities.”
The paper, titled “Taming Hurricanes with Arrays of Offshore Wind Turbines,” appears online on Feb. 26 in Nature Climate Change and will be published in print in March.
stephen rasey says:
“$2 Million/MW (nameplate) is for onshore turbines.
Offshore, in 100 ft of water, rated to survive 150 mph winds, I don’t think you get under $5 Million/MW. $38 million per 7.6 MW turbine. A cool $1,600 Billion, $1.6 Trillion, for a 40,000 turbine wind farm. ”
The link for the cost of the turbines specified at 7.58 mw is:
http://en.wikipedia.org/wiki/Enercon_E-126 or http://cleantechnica.com/2013/08/23/worlds-most-powerful-wind-turbine-may-undergo-high-winds-coastal-tests/
These are Enercon Model E-126 as specified in what appears to be a presentation based on this paper at http://www.energy.udel.edu/wind2013/Jacobson_1302UDelHurrTurb.pdf The relevant passage regarding the specific model states “7.58-MW Enercon E-126 spaced one every 0.45 km^2 within 100 km of the coast in specified areas.”
“The Enercon E-126[1] is a wind turbine model manufactured by the German company Enercon. With a hub height of 135 m (443 ft), rotor diameter of 126 m (413 ft) and a total height of 198 m (650 ft), this large model can generate up to 7.58 megawatts of power per turbine, making it the wind turbine with the highest nameplate capacity. The power output of the generator was changed from 6 MW to 7 MW after technical revisions were performed in 2009. Since 2011 the E-126 is available as a 7.6 MW nameplate windturbine. Actual output in service may slightly exceed the nominal rating. The E-126 incorporates power electronics and offers grid stabilising capabilities.[2]
The weight of the foundation of the turbine tower is about 2,500 t, the tower itself 2,800 t, the machine housing 128 t, the generator 220 t, the rotor (including the blade) 364 t. The total weight is about 6,000 t.[3]
The first turbine of this model was installed in Emden, Germany in 2007.[4]
The list price of one unit is $14 million plus install costs.[5]”
The webpage stating cost for these specific units makes no mention of differing equipment cost depending whether on or offshore. The second link references a project which is specifically offshore.
I specifically stated that was just equipment cost. Your figures show installation costs 3 times that of equipment costs. Offshore I guess it’s possible.
The study stated also a MATURE industry which implied to me production cost decreases and installation cost reductions but … to what extent?
Regardless the actual figures, and I consciously chose to calculate the LOWEST cost and not even guesstimate the installation costs, the projects are essentially insanely expensive and from my viewpoint as an engineer a total waste of money and time to even consider installing given current state of the art or reasonable projections of advances.
1.5 trillion for the minimum effectively sized array may well be good ballpark figure, but even that I would expect to be underestimated.
clarity2016 says:
February 27, 2014 at 9:55 am
I calculated only the minimum equipment only cost which is nonetheless astronomical.
Kate Forney says:
February 27, 2014 at 2:34 pm
http://www.pnas.org/content/early/2012/02/06/1111769109 suggests that without some great improvements in turbines, anchoring, tower structure strength, nacelle orientation etc, about 1/2 will be destroyed by the end of the projected 20 year service life.
So we slow down hurricanes. Mess with natural weather patterns. Sounds like a good idea.
What happens when there is no more weather?
And what happens if they do this and it doesn’t work?
How many people are going to have to die for this foolishness to stop?
It’s difficult to be optimistic when “scientists” come out with stuff like this.
Moderator: I’d never heard of this paper before, but had read something really dubious about renewable energy from the U of Del before. I did a google search for the title of the paper, because I was curious if the rest was as bad as it appeared, especially after RGB and other reported that hurricanes released far too much energy. I decided on my own that certain aspects weren’t as scientifically ridiculous as they appeared. Wind turbines extract energy from the wind, leaving the air exiting them with less kinetic energy than before. On paper, at least, the authors have enough wind turbines to do the job.
We can’t afford to build that many wind turbines. They will lousy producers of electricity, except during hurricanes, when there will be too much.
@onlyme at 7:09 am
Many thanks for the reference and quotes.
I’ll accept $14 Million per 7.6 MW unit as the list price on the factory floor of FOB rail car.
Plus transportation, permitting, installation costs. (shudder).
2,900 tons for the tower ?!? That pushes the capacity of the biggest offshore cranes.
40,000 turbines. Built over 20 years. Seven per day when the weather is good. Times how many days/turbine installation = how many work crews. Wow. Oh, almost I forgot…. It takes 5 years to permit a big onshore pipeline… How long for an offshore wind farm?
I agree: Madness.
Here is a ?Masters Thesis from Caitlin Howland, Digital U of Maine, The Economics of Offshore Wind Energy, May 2012
Fig. 4.1, page 43, has a figure from Levitt 2011 estimating 3.7-5.5 Million / MW, but the cost curve has almost doubled since 2005. I suspect that the capex/MW isn’t linear and increases as the facilities get bigger.
Dudley: If the hub is 130 m above the surface and rotor is 90 m in diameter (45 m in radius), it won’t come closer than 85 m to the surface of the water. However, the dimensions I reported were slightly wrong and therefore some of the area calculations. A German company has built and installed more than 100 Enercon E-126 wind turbines with a nameplate capacity (maximum) of 7.58 GW. These are the type the authors modeled. The rotor is 126 m in diameter. How close to the ground do you think it comes?
http://en.wikipedia.org/wiki/Enercon_E-126
After wind passes through its turning rotor, does it still have the same amount of kinetic energy (velocity as before)? If your answer is yes, review the law of conservation of energy. The dreamers who wrote the article are proposing an array big enough to harvest all of the kinetic (wind) energy contained in a hurricane. Hurricanes are powered by evaporation of warm ocean water and the latent heat released much higher (colder) in the atmosphere. The rate of evaporation depends on wind speed. When hurricanes move inland, the wind slows due to surface friction and there is less water to evaporate. Their damaging surface winds and evaporation subside. If you do the same thing with an array of turbines, the same thing should happen (and does in their model). The problem isn’t the concept (or the idea of testing it with a model capable of representing the key processes powering hurricanes), it’s the practicality.
Stephen Rasey says:
February 28, 2014 at 10:54 am
Thanks for the study link.
I noticed in the masters? thesis that the shallow water base structure is single pylon, not tripod as recommended for hurricane prone areas.
The further into this idiocy I look, the worse it gets.
With current immature technology for hurricane prone areas, an immature industry, high equipment prices which don’t seem to be benefiting from scale of manufacture cost decreases, labor price increases, storage and grid connection problems, salt environment long term maintenance effects, and no provable cost of carbon as there is currently no proof temperatures are increasing globally or that additional #CO2 in the atmosphere is anything other than beneficial to biomass production, I marvel at the thought anyone could seriously propose something like this as a viable solution to anything, whether #CO2 control, #Climate mitigation or modification or extreme weather control.
Thinkbeforeyoulaugh, you might need to thinkbeforeyoupost. Do the Carribean Islands shield the Gulf Coast from hurricanes? Nope. But your wind farms will? To really slow down a Hurricane with friction you need something really big like a Continent. Islands and Wind Farms are just toy cars to a Hurricane.
I think the Scientific Journals should check to see if the authors also write for the SyFy channel.
Maybe SyFy rejected it because it didn’t have enough action?
Gunga Din says:
February 28, 2014 at 3:46 pm
I think the Scientific Journals should check to see if the authors also write for the SyFy channel.
Maybe SyFy rejected it because it didn’t have enough action?
Uh, maybe rejected it because it lacked believability, falling way behind a “sharknado”?
I like Jared’s comment about even large islands not stopping hurricanes. And, as a retired meteorologist, I see so many ways to poke holes in the theory of wind turbines ameliorating hurricane damage that I don’t know where to begin. So, I’ll mention only one that I don’t think anyone else hit upon — did the folks modeling extracted power from hurricane winds consider that the energy of the storm comes from the warm water? Did they model the thermodynamics of hurricanes as part of this study? A wind farm doesn’t cut off the source of energy, so simply subtracting the energy turbines will “supposedly” extract tells us very little about what would actually happen. Here’s my first thought about a hurricane reaching the outer edge of a wind farm. Turbines at the outer edge of the farm either shut down or are damaged when a strong hurricane reaches them … then the next layer of turbines are destroyed or shut down … then the next … I’m sure you get the picture by now.
@Thinkbeforeyoulaugh
“They will lousy producers of electricity, except during hurricanes, when there will be too much.”
You are incorrect. They will produce zero electricity during and / or after hurricanes. There would be a very brief spike in production as the hurricane approached, but the turbines would all be ripped to pieces long before they were hit by the hurricane itself.
@H L Wegley,
It’s worse than you think. The only way they could get even an infinite number of wind turbines to draw as significant amount of energy from a hurricane is to assume a currently unknown material that is both light enough for wind turbine construction and strong enough to stand up to hurricane force winds.
Thinking of hurricane damage…
I remember Platform Thunderhorse after Hurricane Dennis 2010. A very close call.
It took a week to right the platform. Six weeks later it was in the core of Katrina and survived with less damage than Dennis. But had it not been for Dennis exposing an Achilles Heel of Thunderhorse it would probably be on the ocean floor after Katrina.
A Hurricane map of 2001-2005 Cat3 + storms, Looks busy. Yet 2005 was the last Cat 3 landfall we’ve had in the US. We will be over 3100 days since the last Cat 3 before the 2014 hurricane season starts.
Thanks, Thinkbeforeyoulaugh. Me error. The details of the turbine you provide the link for are:
“The Enercon E-126[1] is a wind turbine model manufactured by the German company Enercon. With a hub height of 135 m (443 ft), rotor diameter of 126 m (413 ft) and a total height of 198 m (650 ft), this large model can generate up to 7.58 megawatts of power per turbine”
OK, so the lowest part of the swept circle is 135 – 63 = 72 m above sea level, and the top is 135 + 63 = 198 m above sea level. The area of the swept circle is 12 469 sq m. The area from sea level to 200 m, in the stretch between one turbine and the next – 1 km is 200 000 sq m. Hence each turbine only sweeps through one sixteenth of the csa of the hurricane up to 200 m.
In a previous post I assumed that the rotating cross sectional area at full strength would be the full height to the tropopause, perhaps 17 km. Think – the rotating mass is doing that because at the centre the air is sucked upwards, and so somewhere the air will have to be blown out of the Hurricane. So I will cut the area to be considered to only 10 km high. 200 m is one fiftieth of that distance, so all the turbines in one row, even if able to extract 100% of the energy of the air passing through their swept circles, would only be able to extract 1/16 x 1/50 of the energy of the hurricane. This, if my maths is correct this time, is 0.125% of the energy. Succeeding rows will be able to extra energy – 10 rows might be able to extract 1.25% of the energy. 100 rows may be able to extract 12.5% of the energy – perhaps. IIRC someone posted that a turbine can extract 1/3 of the energy of the wind passing through the swept circle. If this is right, those 100 rows will be able to extract about 4% of the energy. That is, of course, if that energy can be safely delivered ashore, and used, or stored.
If my calculations are wrong again, please let me know so I can apologize!
Correction to 8:04 pm, Thunderhorse and Hurricane Dennis was 2005, not 2010.
I heard a news story the other night, where they were calling for building walls to keep ot tornados in the USA.
These walls, would be 1,000 ft tall, and I think they said 150 ft wide. I guess they would have gaps, to let people and cars through. Tornados would not be allowed to go through the gaps.
At no time in the news bulletin, did they say the walls would need to be able to withstand tornado wind speeds.
I suspect that Dubai, might bid on a contract to build the walls. They seem to be able to build structures that are a lot nuttier than anyone else can.
Heaven knows, what hurricanes might do to a tornado fence, so Tampa’s Tornado Alley, may not get protected.
Imagine having a 1,000 ft deep swimming pool in your back yard. The higher the walls, the deeper the pool; ask N’Orleans !
Assuming for the moment that his wind turbines actually can stop a hurricane, has he also determined the effect those turbines will have on climate in the same area?
Well I think that it is obvious the same effects they have on a hurricane will apply that all winds will be slowed (And how will that effect the windmill economics?) and evaporation (possible drought along the Gulf coast), as well as being fairly good cloud spreaders for any rain coming from the outside.
Somehow I don’t think the idea will pass the environmental review. The cure looks to be worse than the problem.
Dudley: Your second response sounds much more reasonable. I don’t claim to have proved their idea must work; just that there is some reasons for thinking the science could work. The fundamentals I trust are: 1) Turbines extract about half of the kinetic energy in the wind that passes though their rotors when operating. 2) The capacity of the total array is comparable to the kinetic wind energy in a hurricane. I shouldn’t have speculated about layout and how many time the average packet of wind might pass through the rotor of a turbine; even once (50%) could be significant. However, a hurricane is clearly not going to pass through all of the turbines and the turbines are not high enough reach all of the wind. Turbines can sever the critical linkage (high winds) that dramatically increase evaporation from the warm ocean surface and carries the water vapor to the colder upper troposphere – the heat engine that powers hurricanes. Once that linkage is weakened (as happens when a hurricane moves over land), the hurricane should begin to dissipate. Unless the remaining upper level winds can regenerate surface winds, the main mechanisms by which hurricanes cause damage (wind and storm surge) also will be weakened. The authors demonstrate this weakening with their model, but I don’t know anything about the reliability of hurricane modeling.
Could work – Once.
Did they come up with any estimates of what a Cat5 hurricane, like Katrina when she was out in the Gulf, would leave left of the thousands of wind turbines over run by the storm?
Seems like a very cost ineffective method of hurricane damage mediation. Probably much more cost effective to discourage people from living in below sea level cities, barrier islands, or other places known to be frequently clobbered by hurricanes.
W^3
george e. smith says:
I heard a news story the other night, where they were calling for building walls to keep ot tornados in the USA.
Just came across that, too. Here’s a link to a story about it: http://www.usatoday.com/story/weather/2014/02/25/giant-walls-tornado-alley/5808887/
It’s being presented by Rongija Tao from Temple University at the March meeting of the American Physical Society
RE: usatoday giant walls in tornado alley
The walls would need to be about 1,000 feet high and 150 feet wide, he said.
Wide? No 1,000 feet high, 150 feet THICK, and hundreds of miles wide (or long). Estimated cost $60 billion per 100 miles. 600 million per mile? 30 million cubic yards of wall per mile for $20 per cubic yard? Even if we make the cross section an isosceles triangle, it is still 10 million cubic yards / mile.
Forget the economics. Let’s just look at the meteorology. I wager that wall would be an excellent for the generation of wind sheer and gigantic “rotors”, horizontal wind eddies that can breakup and become the seeds of tornados. After the wall is built, we can expect tornados every day about tea-time.
This guy’s cure is worse than the disease.