An Answer for Offshore Wind?
by Jeff McIntire-Strasburg, St. Louis, MO on 05.12.06
We US-based Treehuggers have been following the battle over the Cape Wind Project in Nantucket Sound for several years now, and the fight between wind energy advocates and homeowners determined to keep the Sound free of offshore wind turbines continues to drag on. MIT's Technology Report notes that such battles may quickly become irrelevant as GE and the US Department of Energy have announced a partnership to develop larger wind turbines that will be able to not only generate more power, but may be able to do it offshore at distances that wouldn't bother even the most diehard NIMBYist.
MIT researchers recently demonstrated the feasibility of "tension-leg" platforms, a technology that oil companies have recently adopted for deep-water rigs. The wind turbines and towers would be assembled at a shipyard and placed on top of large floating cylinders (see images). The canisters would be ballasted on the bottom with high-density concrete to keep the structure from tipping over, and the whole turbine assembly would be tugged out to sea.There, four steel cables would be attached to the platform, anchoring it to the sea floor. First, though, some water would be allowed into the cylinder, causing the structure to sink more into the water. Once the cables are attached, the water is pumped back out again, allowing the turbine to rise, tightening the cables, and preventing the turbine from bobbing up and down, yet allowing some lateral movement that would help cushion the impact of storm waves on the tower. (The blades themselves would be high enough to avoid even waves from hurricanes.) The cable tension can be adjusted for different weather conditions, says Paul Sclavounos, professor of mechanical engineering and naval architecture at MIT.
Based on wind-speed measurements, researchers at MIT, led by Stephen Connors, director of the Analysis Group for Regional Electricity Alternatives, calculated that large turbines located far offshore could ultimately cost less per power generated than either land-based turbines or near-offshore ones, even factoring in extra costs, such as much longer underground electricity transmission cables. The upside: much more fast and steady wind, which would allow the turbines to generate power at 50 percent capacity on average throughout the year, compared with 30 percent or less with on-land turbines.
Offshore wind farms could also have the advantage of being close to big cities, unlike wind farms in remote areas, which require significant power grid upgrades to transport the power to places where it's needed. "I personally see this as the endgame," says GE's [Jim] Lyons. "We'll see gigawatt-scale projects delivering clean energy to the East Coast."
As GE and the USDE are shooting for a 2009 completion date, the bluebloods and windpreneurs will still have plenty of time to squabble over Cape Wind. By that point, assuming the project's engineers overcome the numerous technological challenges of building such large turbines, we may be able to have both our unspoiled views and green power from offshore wind farms. :: MIT Technology Review via The Energy Blog
That sounds great i want those on the west coast.
So, what this post is saying is that this would "take all the wind out of the NIMBY Cape Cod wind project protesters?"
couldn't resist.
Although I am currently studying in Georgia, my hometown is Nantucket, Ma. This article mentioned that the argument over the wind farm in Nantucket Sound was between "bluebloods and windpreneurs." I would like to point out that it is a misconception that the entire population of my town is part of the upper crust and only want to preserve their yaughting grounds. For example, my father, a local fisherman, is interested in the wind turbines because they threaten to disturb the undersea ecosystem on which his livelihood depends. The vibration caused by the wind farm has the ability upset the sonar in whales and other aquatic mammals. Their bases will change the build up of sand, thereby changing the shoals and the currents, whiich in tuen will change life for sea creatures, including those for which my father fishes. In addition they will create a lot of noise which it may be possible to hear from shore (probably dependant on the wind direction and strength). Something that loud cannot go unnoticed in an ecosystem. Moving the wind farm farther offshore may or may not positively impact these issues, however, it is worth noting that the local people are concerned about their environment, not only their money, as your article suggests.
Thanks for pointing this out, Amelia... I suppose I did show my biases here. In fact, it's a shame that locals haven't gotten more attention for their concerns -- generally, all we hear about are the bluebloods...
I've been around several wind farms in Europe and they aren't loud at all. They are really quiet. The comments about the ocean floor are justified, though I have to say that with barnacle growth on them I'm betting the fish would actually flock to the area rather than stay away from it. When it comes to the yachting, I see it going both ways. They'll have the ability to do serpentines through them when they get a bit loaded on their drink of choice.
I wanted to second concerns over the environmental impact of off-shore turbines. While I am a HUGE supporter of wind power (check out the wind turbine Carleton College - my "alma mater" - put up: generates equivalent of 40-45% of the school's energy, we are trying to get a couple more!), I am also very passionate about marine ecology and my sister is an oceanography student. The impact of construction to stabilize a large number of turbines - in a tidal area or even farther off shore - is not something to be taken lightly. I'm still not sure whether the benefits might outweigh the costs, but it's certainly not a black and white issue.
just currious- how do high voltage transmission cables affect marine life? I know that it is hazardous for mammals to be near high voltage, and I remember reading that sharks are sesitive to electricity. Are underwater wires harmfull?
Otherwise- good news!
Its funny but I don't see them complaining about the US Navy's sonar network that messes up the sonar in aquatic animals.
As for people not complaining about things they can't see, remember the saying "out of sight, out of mind"? ;)
What I would like to see them do with these platforms (that I don't understand why the oil platforms don't do) is to combine the wind generation with wave action and ocean thermal. That way you should conceiveably have constant generation of power whether there's wind or not.
And I would think with the tension-leg system that you're not going to have the problems of sand build up since very little actually rests on the ocean floor. It's basically like a weather balloon tethered to the ground. You'll just have to search on "tension-leg platform" to find any decent diagrams of how it works. Wikipedia was no help that way...
I'd like to see thse babys in the middle of lake Michigan, just out of sight of land! Shallow water, constant wind.
I have never had a problem with wind turbines on land, I've always thought they look good on the landscape and the noise they make is more calming than instrusive.
But I had never thought of wind turbines out at sea, what a great idea! - Two thirds of our world is covered by water surely, the environmental impact would be tiny, especially when it is replacing coal mining and all those nasty carbon emissions from power stations.
Oh get real. Let's take the most dire predictions of the damage off-shore turbines (Cape or otherwise) could cause and compare them to one coal burning power plant. Hmm... let's see... Wind wins that one!
Let's compare it to building a few off-shore oil rigs. Hmm... let's see... Wind wins that one!
Let's compare it to building a new nuke. Hmm... let's see... Wind wins that one!
Sure, we have an opportunity to implement off-shore wind in a responsible, scientific manor. Might as well. But what's the worst that can happen... they have to move the turbines??? Friggin DUH!!!
As a resident of Nantucket I have to tell you that there is much more to this issue than what you presented here. PLEASE do not think that all of Nantucket (Cape & Islands) are wealthy. There is a very definate working class here that barely make ends meet. These are the people that keep the island running for all who come to enjoy the beauty that surrounds it. I personally find windmills mesmorizing and a wonderful green(er) alternative. However I do beleive that they are better on land for a multitude of reasons. There have been many meetings and forums to hear peoples concerns. In a recent non-binding ballot question the people of Nantucket were asked, yet again, if they were in support of the wind farm. They are not. In an exit poll some interesting information emerged as to the reasons why not. One that suprised the poll takers was that people are very opposed to public lands (the ocean) being used for personal/private financial gain (the developers of the project). In it's original presentation, the Cape and Islands were not going to receive significant benefits from the power generated here. That has changed slightly.
As for putting wind farms in deeper waters, the technology sounds interesting yet being enviromentally aware means looking at the issues completely, not just passionately. We have to be very aware that there is a whole other ecosystem that lives in our oceans, one that migrates and is easily upset. We must tred lightly and reduce consumption in all aspects of our lives.
Hey - if you don't want the windmills, then you shouldn't expect help when the oceans start to take swallow Nantucket and MV. We landlubbers are trying to do our part with windmills. You should too.
I beleive in and understand the need for alternate energy. I also "get" that this is not the only place we'll need to build these turbines. This one proposal will only offer a small supply of energy in the grand scheme of things. I'd like to propose that we start building the turbines on every capped land fill there is, and will be in the future, across the country. I don't know of many people who want to fight to preserve a former dumping station.
As for the natucket sound project. I am a wash-ashore. I've only been on the Cape fpr 30 years. I DO NOT WANT this built in the sound. On a clear day we can see the islands from our mainland shores. So, don't tell me that the current proposed site will be far enough off shore to not be heard or seen. I don't want to sit idly back and have them build this and then say OOOOPS we didn't realize they'd be so intrusive.
As for these new and improved turbines you write about being bigger and better and build further away.....Show me I guess we'd all have to say.