Slashdot Mirror
Floating Wind Turbines
The Great Pulgoso sends us word that Norwegian energy group Norsk Hydro has signed an agreement with Siemens to develop floating wind turbines. The companies agreed on a schedule that would see a prototype in the North Sea by 2009 and a working wind farm using 5-megawatt generators by 2013. (Norsk Hydro unveiled the design in 2005.) Inhabitat.com has taken the giant illustrations from the Norsk Hydro site and reproduced them at a reasonable size. The design features a steel tube 200 meters long. It extends 80 meters above the sea surface and has three 60-meter blades. The whole thing is anchored to the sea floor by three tethers. The developers expect to be able to install the turbines in waters up to 700 meters deep.
Destroying habitats on the ocean floor and having birds fly into it won't go over well for the environmentalists I imagine.
The whole "floating" thing is trying to solve that. By floating they can be located farther offshore, outside of migation patterns and coastal wildlife habitats. Sure they might need to make some sort of passive sonar reflectors to keep whales from hitting them, but being able to be in 500m water will also put them well out of sight of land, another NIMBY adoption problem.
We are all just people.
Much like other interaction with the sea floor, the tethers could actually create habitats. The tether points would probably provide a little shelter for smaller wildlife. You could attach small platforms along the submerged tube to encourage small plants, fish, etc to attach themselves.
And environmentalists that oppose everything cannot speak for everyone. Opposing greener energy sources just hurts everyone, nature included. If we can't build greener sources, we're going to burn more coal. When comparing a few dead birds vs. a coal plant, I'll take the few dead birds any day, and so should any reasonable environmentalist.
I wonder if these things will reduce the number of hurricanes. It seems that strong hurricanes don't form in the presence of wind shear between surface and higher altitude winds. With enough of these things scattered across the ocean, the drag on low-level air masses should set up a shear condition that helps reduce the formation of intense hurricanes.
On the other hand, weather modification seems a dicey thing to try on our sample-size-of-one planet.
Two wrongs don't make a right, but three lefts do.
I can't comment about other parts of the world, but in New Zealand the main resistance to wind farms is that nobody wants them in their back yard. They're big, ugly, and noisy, they tend to restrict public access to the surrounding land, and they cause the all-important property values of private individuals to plummet. Lately we've seen several local large wind farm projects either heavily toned down, or completely scuttled. Each has been worth between hundreds of millions and billions of dollars, but small groups of locals have put a lot of effort into blocking them.
Even though I have mixed feelings, I do actually sympathise with many of the complaints. Society (here at least) has been built to encourage people to value personal property and what they own, and property ownership is a very traditional and encouraged way for people to invest for their future. People here have their retirement funds in their property, and suddenly seeing that value plummet by 50% or more because the local council or government decides that it might allow a wind farm nearby can be quite devestating. 20 years ago, nobody would have guessed that there would be an incentive to build giant noisy ugly structures all over the countryside, and there's only so much forward thinking that can be done.
Even if it's kind of silly and inefficient, putting wind farms out at sea conveniently places them in a location which isn't the back yard of anyone likely to complain.
It solves a couple of problems with wind power, but doesn't really address the main ones.
A) Wind power is expensive
B) The power output is uncontrollable and unpredictable
Wind power is not being held back by environmental concerns. On the contrary it receives huge subsidies based on its renewable nature. The reason it haven't caught on is simply that it is 3-4 times as expensive per kwh as compared to a fossil fuel plant or nuclear power station. The unpredictable output would be a show stopper if you want any large fraction of your energy from wind, but in most countries today the amount of wind power used is not even close to when this starts becoming a major problem. For wind power to catch on costs must come down by a factor of 2 at the very least, and I don't see that happening by making them significantly more difficult to deploy and maintain.
not compared to coal fire plants. I'd much rather see a wind farm than a coal fire plant.
How about floating, or submerged, platforms anchored to the bottom, with turbines pushed by the water currents flowing past them? The energy to move less viscous, less dense air in the volumes past windmills is much less than the viscous, dense water flowing beneath these platforms. And those currents are more predictable than the winds. While the weather (eg typhoons and lightning) probably makes air turbines more subject to damage than submerged ones.
Anyway, why choose? Why not water turbines submerged beneath platforms with windmills mounted on top?
--
make install -not war
I was gillnetting for salmon in Puget Sound years ago. The net was monofilament and meshed for sockeye. At night, a grey whale swam up then down the whole half mile length of net. They know what is in the water.
s -selling-solar.html
On birds, the very large wind turbines turn quite slowly and this has proved much better for birds since thy fly faster than the blades move.
--
Solar, the source of renewable: http://mdsolar.blogspot.com/2007/01/slashdot-user
Actually, I think the biggest problem/risk is shipping. It would kinda ruin your day if something like Pasha Bulker decided to take out several of your wind turbines.
This is particularly the case with wind turbines, since the quantity and extent of distribution of the structures would be much more significant than offshore oil & gas installations.
I always figured some kind of power generation on a floating platform at sea could be a spiffy way to generate hydrogen (and oxygen) using electrolysis. Just come by every now and then to collect the hydrogen and replace the anodes (which would probably corrode really really fast in salt water) and you are set.
I Am My Own Worst Enemy
But....these will block Ted Kennedy's view of Norway!
Seriously..all these people complain about wind turbines blocking the view of their million-dollar ocean cottages get no sympathy from me. They ought to think about the value their oceanfront property will have when the oceans rise thirty feet because the polar ice caps melt due to global warming. Oh wait, NIMBY! I forgot! Make it someone else's problem!
At 5MW, the wind will push on the rotor with a force up to 500kN or 50 tonnes and 50MNm of torque
/. that care to comment?
This is both a huge bending moment and dragging force.
To keep the mill from leaning more than 45 degrees backwards, it will need hundreds of tonnes of ballast,
With the windmill leaning backwards, the blade on one side will see a higher load than the blade on the other side, and the whole windmill will see a torque of maybe 10 MNm along the vertical axis.
How they plan to keep this stable is a mystery to me, and TFA does nothing to suggest a solution.
Anybody working for Hydro here on
don't cut it off www.mgmbill.org
That is complete nonsense.
Many/most environmentalists are environmentalists _because_ they want to preserve humanity, and human civilisation. David Suzuki is a good example.
Your comment is as stupid as saying that uranium miners drink the blood of African children.
the blades are composite...salt water no problemo
It seems that no one is addressing what seems to me to be a major concern about putting anything valuable far out in the ocean. It is very difficult to protect it from intentional destruction.
Defense of power generation facilities is a low priority on land because your country's armed forces protect it and everything else that is within the borders. Outside of the country's landmass, it becomes difficult to protect major power installations. If your region's power requirements are substantially provided by far off-shore generators, then any bozo with a big boat and a big gun on his big boat can shut down your region's power grid for months. In fact all it takes is one Allahhead with a Cessna loaded with TNT to shut down the grid, if he knows which ocean tower is the central command-and-control unit of the power cluster.
Granted the vast amount of ocean is going to mitigate the mischief, but it isn't going to stop submarine torpedos from psycho rogue governments or even agent-provocateurs from your 'friendly' neighbors. No, you have to get out there and patrol, patrol, patrol. Which costs a lot of money. And whose expense is never entered into the cost-benefit estimate reports before these types of projects are built.
So yeah, it's one thing to build this project in the middle of the God-forsaken North Sea and another to build it fifty miles off the West Coast of the USA.
It's not an "unspoken truth" - it is a well acknowledged and open fact that the north sea is running out of oil and gas. No-one is trying to hide this. This is why there is a major gas main into the UK from mainland Europe now. And Norsk Hydro is very forward thinking with its R&D efforts. This ends up costing the company I work for quite a lot in patent licence payments!
Regarding waves...
The design reminds me of FLIP -- the Floating Inertial Platform -- of Scripps Oceanographic.
It's basically a huge buoy consisting of a ship like prow on a long steel cylinder. It is towed into place and the end of the cylinder is flooded, causing the prow to be jackknifed into the air above the ocean surface, providing a quiet, highly stable platform from which to perform oceanographic research. The vessel is so stable that when a large wave hits, it doesn't tilt at all, although researchers are sometimes thrown from their seats by lateral motion.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.