Next Generation Energy is managed and written entirely by Seed editors and expert guest bloggers. Read more about them New York City. Center of the universe.
Just imagine: It's 2018 and you stare up at the Brooklyn Bridge's gently revolving turbines. The taxis whir by, roasted nuts scent the crisp afternoon air, and you watch the giant windmill atop the Empire State Building turn round...
The scene might not be all that far-fetched. Maybe. You see, just last week Mayor Michael Bloomberg announced he wants to harness the power of wind throughout the city to generate a lot more electricity. He's proposed placing them on bridges, skyscrapers, and building turbines in the Hudson and East Rivers.
"If you could get 2 or 3 percent from wind, and from solar -- and the potential's greater than that -- you really could make a difference."
Well, I've said it before, I'll write it again, New York City is the greatest and greenest city in the world. It's also my hometown. And it may be easier to transition to wind than you'd expect. Marquiss Wind Power, an innovator in developing and deploying wind turbine technology, has already offered to deliver and set up a roof-top wind turbine in the city. Further, offshore farms 15-25 miles out would hardly be visible and New Yorkers will get to decide where they want windmills.
So how does wind power work? Turbines turn a generator to produce electricity, which gets transmitted on a line and through a grid. It's currently more expensive than regular power by 2.5 cents per kilowatt hour, but if expansion continues, may save money down the road--especially as the price increases for other energy sources.
Sure, some questions do arise... the danger of the spinning blades, installation costs, and determining whether city buildings can handle the weight. But despite unknowns, one thing's for sure... When the mayor of NYC proposes incorporating windmills into the city's design, it's a sure sign that, as Dylan sang, 'The Times, They Are A'Changin'.
So readers, how would you feel about a new spin on the Big Apple skyline? And further, how long until you think we'll see multiple cities follow suit?
Environment
Comments
Well, I think it's great. Harness more green power everywhere. (But New York is still a well-appointed dump.)
Posted by: Woody Tanaka | August 27, 2008 9:23 AM
MOAH POWER!!!
Ahem...
I think innovating green power sources in new building design is an excellent idea.
Posted by: zayzayem | August 27, 2008 9:56 AM
determining whether city buildings can handle the weight
That's the kicker for me -- and aren't there some hefty lateral forces produced by turbines as well? (Answer: Yes, obviously. You're robbing the wind of a lot of momentum to spin those blades). So it's not just the weight, but getting a solid anchor from the pylon to the existing structure that's a concern.
And imagine one of these things failing like that Danish one (it was on YouTube), but 50 stories up, in an urban environment....
Not trying to be alarmist, but it's a significant concern.
Posted by: Eamon Knight | August 27, 2008 10:11 AM
They're less efficient, but wouldn't vertical axis turbines be useful to avoid the difficulty of buildings not being designed to take the large lateral forces of horizontal turbines?
Posted by: Fair Trade | August 27, 2008 11:40 AM
They're less efficient, but wouldn't vertical axis turbines be useful to avoid the difficulty of buildings not being designed to take the large lateral forces of horizontal turbines?
In a word: no.
Whatever turbine design you use, it is resisting the horizontally-blowing wind. The vertical axis things are attractive for capturing wind from any (horizontal) direction. But the forces will still be the same as a regular windmill, or even just a big brick wall, facing into the wind.
Posted by: kevin | August 27, 2008 12:34 PM
Care to comment on the issues raised in the brand new NY Times article on a big problem that's emerging with incorporating wind-generated energy into our system? I had no idea that this was a problem.
"When the builders of the Maple Ridge Wind farm spent $320 million to put nearly 200 wind turbines in upstate New York, the idea was to get paid for producing electricity. But at times, regional electric lines have been so congested that Maple Ridge has been forced to shut down even with a brisk wind blowing.
That is a symptom of a broad national problem. Expansive dreams about renewable energy, like Al Gores hope of replacing all fossil fuels in a decade, are bumping up against the reality of a power grid that cannot handle the new demands."
Full article can be found here:
http://www.nytimes.com/2008/08/27/business/27grid.html?_r=1&hp&oref=slogin
Posted by: Mark F. | August 27, 2008 12:36 PM
@Mark F - The grid issue is a significant one, but in this particular case, I don't think it is all that relevant. This post talks about putting the wind turbines very close to the population that will use the electricity generated by them.
Posted by: sdg | August 27, 2008 12:56 PM
@Mark F: That's an example of an engineering problem, not a fundamental problem. It will be solved by clever engineers in any of a hundred almost equally-practical ways. One such way is to compress air into tanks. Compressed air may also be used to absorb heat from solar thermal collectors, and even be augmented, at need, by combusting with natural gas, all driving the same turbine.
Posted by: Nathan Myers | August 27, 2008 9:08 PM
Nathan -
You do realise that compressed air storage is very lossy, due to heat losses (compressing air heats it, and the heat is lost in storage).
In general, any renewable/storage scheme should obey this equation:
n = 1 + ((1-Cp)/(Cp*Se))
For relaible generation, where Cp is the capacity factor, and Se the storage efficiency, and n is the nameplate multiplier.
For example, a wind farm with a Capacity factor or 0.3 and a storage efficiency of 0.5 would need 5.7MW of capacity to reliably deliver 1MW of baseload.
When wind is simply used to displace other dispatchable sources (i.e. Hydropower, natural gas), this isn't an issue, as long as the efficiency of the displaced generation isn't affected - which is a problem with modern CCGT natural gas plants. However, once you try and get a significant chunk of supply from wind, it becomes a very serious issue.
There may be many engineering solutions to intermittancy, but they come at both an energetic and financial cost.
Posted by: Andrew Dodds | August 28, 2008 8:51 AM
This is an engineering problem, and is (in principle) soluble. Multi-stage compression helps a lot, and there is also the possibility to store (or otherwise use) the heat of compression. This article on the European Advanced Adiabatic Compressed Air Energy Storage project may be of interest - unfortunately I don't have access... However, I do know that they were hoping to achieve round-trip efficiencies of better than 70%.
Posted by: Dunc | August 28, 2008 12:04 PM
@Andrew: Underground storage tanks can retain heat well. Above-ground tanks may be insulated cheaply. Anyhow, if the problem being solved is smoothing production spikes, there might not be time to lose much heat. In circumstances with an effectively unlimited heat sink (e.g. near a water reservoir) heat may be discarded and then recovered freely.
Air compression is much less attractive for storing energy for long periods in portable tanks, or for energy delivery via plumbing, for the reasons you note.
Posted by: Nathan Myers | August 28, 2008 10:29 PM