Power Generation and Windmills

[Arken]

What with the big power outage, I'm sure everyone's been thinking about ways to generate more power safely. I was wondering if anyone here would know how much power could be generated if you put windmills on top of all of the buildings in NYC. Would it be worth the cost?

[DigitalChicken]

That would look really cool.

DC

[Mageth]

And think of all the freshly ground grains the New Yorkers could enjoy!

[Arken]

Originally posted by DigitalChicken
That would look really cool.

DC

That's sort of why I thought of it :cool:

But seriously, windmills have been used at least somewhat successfully in places as power generating mechanisms and the winds atop tall buildings tend to be pretty high so would that be a cost-effective way to generate power for the city?

[Coragyps]

There are hundreds of those suckers on all the mesas out here in nowhere - three 75-foot long blades, and they only rarely break off. I don't know how much power they actually contribute to the grid, but someone is making money on them - about a hundred are going up twenty miles from here right now.

A big advantage of windmills in the big city would be the amount of shredded pigeon they could produce. :D

[SpeedDemon]

These guys (http://www.energyinnovations.com/) look like they have something really interesting in the works. I'm not sure about powering a city but a few of them would do a pretty good job running a modest single-family house.

SD

[markfiend]

From here (http://www.eere.energy.gov/wind/feature.html):

"Utility-scale turbines range in size from 50 to 750 kilowatts."

NYC power consumption is approx 5 gigawatts (source here (http://hypertextbook.com/facts/2001/PollyHo.shtml))

Plug in the numbers...

7000 750kW turbines would generate 5.25GW (providing extra for peak demand). Are there 7000 skyscrapers in New York City?

[Risiko]

Originally posted by Arken
...
But seriously, windmills have been used at least somewhat successfully in places as power generating mechanisms and the winds atop tall buildings tend to be pretty high so would that be a cost-effective way to generate power for the city?

In Denmark there are few tall buildings but many windmills, many of them at sea. AFAIK 15 to 20 percent of our consumption of electricity is covered by wind energy.

I would guess that buildings, low or tall, generally aren't designed for the extra sideways load generated by a large windmill, which necessarily decelerates a large amount of air.

[Majestyk]

I don't think the structure of the overall building would be affected to much more stress than it recieves currently. The structure of the roof floor joists would have to be augmented to accept, the weight of the winmill as well as the stress that high winds would place on the windmill's anchorage.

Seems doable, as a matter of engineering, though.

Then again, NYC could reduce its energy requirements by adding a layer of bio-mass onto its rooftops.

[Invisible Insanity]

Originally posted by Arken
What with the big power outage, I'm sure everyone's been thinking about ways to generate more power safely. I was wondering if anyone here would know how much power could be generated if you put windmills on top of all of the buildings in NYC. Would it be worth the cost?

I'm a big windmill buff. I'm in the process of building my own. They are actually not that difficult. Unfortunately many townships do not allow windmills. The reason from what have heard is that they can fall. A windmill has to be placed pretty high up for it to work properly, because you want the winmill to take advantage of the naturally constant wind currents. so in a sub-urban town like mine I have to clear all of the trees and houses which would be at least some 40+ feet. As to your question about the actual energy produced by a windmill, that all depends on the blades span and wiring, and not on the height of the building. The only advantage for clearing other buildings is the constant wind current. It can be worth it, but the problem of storing energy is a huge problem. The energy produced by a windmill is AC current and the only way to store [excess] energy is in the form of batteries which is DC. A home built PMA (Permenant Magnet Alternator) with a blade span of about 7 feet can easily produce around 300+ Watts of constant power. Not bad in my opinion.

[Coragyps]

Back in the 1930's or so, before rural electrification, a lot of farmhouses supposedly had windmills with DC generators and bunches of lead-acid batteries - I suppose they used 6 or 12-volt lighting. That doesn't work real well for air conditioners or microwaves, but then a Philco radio was the highest-tech thing they had back then.
I've always been under the impression that the windmills themselves were the style that you still see for pumping water. I would guess that there are newer designs that are more efficient.

[Derec]

Actually wind power is not constant and is a slave to changing wind conditions. If there is no wind, you don't produce any power, if there is a storm you likewise don't produce any power, because you have to swing the blades out of the wind lest the blades get damaged/torn off.

Due to high variability of wind power a distuption of power supply would actually be more likely. What would need to be done to avoid this is full conventional backup which results in no net savings in conventional power plants and actual increase in need for transmission lines.

Originally posted by markfiend
From here (http://www.eere.energy.gov/wind/feature.html):

"Utility-scale turbines range in size from 50 to 750 kilowatts."

NYC power consumption is approx 5 gigawatts (source here (http://hypertextbook.com/facts/2001/PollyHo.shtml))

Plug in the numbers...

7000 750kW turbines would generate 5.25GW (providing extra for peak demand). Are there 7000 skyscrapers in New York City?

A 750 kW turbine does not produce 750 kW of electricity constantly. Most of the time it produces less than that and sometimes it provides zero.

A better idea would be to put some solar cells on the roof and along the outer walls on upper floors of the skyscrapers. The extra power generated would correlate nicely with the AC demand of the buildings. Also, these buildings are office buildings that have very little power demand during the night when sun does not shine. It would not be nearly enough to provide for the energy use of the city, but it would lift some strain off the long distance power grid.

UMoC

[Vorkosigan]

Uglyman, the variability of wind can be made up for by building more capacity in different places. In point of fact, of the major power supply systems, wind has the lowest downtime.

Wind is my numero uno choice for the future. See the American Wind Energy Association for all the latest facts.

www.awea.org

and enjoy!

Vorkosigan

[cube]

My Idea: Just a draft but you see where I'm getting at. This sort of device would be extremly dangerous at high-speeds but if you were to install a couple at every intersection in downtown NY we would start seeing them power every block. If you do not understand from the drawing above I'll explain: When a car passes over the steel rectangular platform it pushes it down spinning the axel comming out of the electricity generator, when this axel spins it generates electricity wich could be used for different purposes. This, of course, is not yet fully thought out idea. there are very evident improvements and changes that need to be made.

[Derec]

Originally posted by Vorkosigan
Uglyman, the variability of wind can be made up for by building more capacity in different places.

Since wind is very widespread a little wind in NYC would likely mean little wind for 100s of miles. So you would have much increased demand for transmission lines. Also, in case wind fails in both areas simultaneusly you still need a more predictable backup.


In point of fact, of the major power supply systems, wind has the lowest downtime.


- wind is not a major power source.
- how do you figure wind is more reliable than coal, gas or nuclear?


Wind is my numero uno choice for the future. See the American Wind Energy Association for all the latest facts.


I myself am more partial to nuclear (including fusion in the future) aided by photovoltaics.

And I don't think a wind power advocacy group would be particularly unbiased.

UMoC

[Arken]

Originally posted by cube
My Idea: Just a draft but you see where I'm getting at. This sort of device would be extremly dangerous at high-speeds but if you were to install a couple at every intersection in downtown NY we would start seeing them power every block. If you do not understand from the drawing above I'll explain: When a car passes over the steel rectangular platform it pushes it down spinning the axel comming out of the electricity generator, when this axel spins it generates electricity wich could be used for different purposes. This, of course, is not yet fully thought out idea. there are very evident improvements and changes that need to be made.

Cube! I had the same idea myself once, except on a grander scale... at all the on and off-ramps of the nation's interstates. It would have to go into storage batteries because the amount of power generated would be uneven but over the long-term I bet it could generate quite a bit using a system that is essentially already in place!

[Vorkosigan]

how do you figure wind is more reliable than coal, gas or nuclear?

Because those massively subsidized plants are offline more often than wind plants are.

If you don't like the AWEA -- biased, good heavens! -- then by all means check out the ENergy Information Administration of the DOE.

www.eia.doe.gov

The Wind Page is here (http://www.eia.doe.gov/cneaf/solar.renewables/page/wind/wind.html)

However, the AWEA has much better and more reliable information, including the latest systems going in all over the US and the world. The EIA is usually about a year or so behind. That's why i recommended the AWEA page. The utility-scale page is here. Take a look! (http://www.awea.org/utilityscale.html)

[Risiko]

Originally posted by Arken
Cube! I had the same idea myself once, except on a grander scale... at all the on and off-ramps of the nation's interstates. It would have to go into storage batteries because the amount of power generated would be uneven but over the long-term I bet it could generate quite a bit using a system that is essentially already in place!

Well, as I understand it, Cube and you wants to steal some kinetic energy from cars and convert it to electricity or whatever, so it's perhaps better to install the converting mechanism on the off-ramps only, or the drivers might get annoyed.

How much kinetic energy does a car moving at, say, 60 mph possess? Not much, I guess.

[Arken]

Originally posted by Risiko
Well, as I understand it, Cube and you wants to steal some kinetic energy from cars and convert it to electricity or whatever, so it's perhaps better to install the converting mechanism on the off-ramps only, or the drivers might get annoyed.

How much kinetic energy does a car moving at, say, 60 mph possess? Not much, I guess.

Sure, not much, but done over and over again day and night on interstates and it adds up.

[jayh]

Originally posted by Arken
Sure, not much, but done over and over again day and night on interstates and it adds up.

That's not free energy. It reduces gas mileage of the cars and increases pollution.

[Arken]

How much gas mileage could it reduce if it was only on the on-ramps?

[jayh]

Originally posted by Arken
That's sort of why I thought of it :cool:

But seriously, windmills have been used at least somewhat successfully in places as power generating mechanisms and the winds atop tall buildings tend to be pretty high so would that be a cost-effective way to generate power for the city?

There is a huge fight off Cape Cod. A provider wants to build an offshore wind farm (pretty much at the horizon from land) and the locals are doing everything they can to stop them.

j

[Arken]

Originally posted by jayh
There is a huge fight off Cape Cod. A provider wants to build an offshore wind farm (pretty much at the horizon from land) and the locals are doing everything they can to stop them.

j

What's their reason for wanting to stop them?

[lpetrich]

Because they can't stand the sight of them.

[Thor Q. Mada]

Originally posted by markfiend
From here (http://www.eere.energy.gov/wind/feature.html):

"Utility-scale turbines range in size from 50 to 750 kilowatts."

NYC power consumption is approx 5 gigawatts (source here (http://hypertextbook.com/facts/2001/PollyHo.shtml))

Plug in the numbers...

7000 750kW turbines would generate 5.25GW (providing extra for peak demand). Are there 7000 skyscrapers in New York City?

Yes, and that is a peak wind speeds only. At the moment, windmills cannot replace conventional powerplants by any approximation, and by thew way, the black-out was not caused by the lack of generating power, but rather by a breakdown of the net. Don't dream. Dreams don't come true.

[jayh]

Originally posted by lpetrich
Because they can't stand the sight of them.

NIMBY

Though in the interview with a newspaper reporter, the one experimental tower that is there now is barely visible from land.

There was strong resistance to the Eiffel tower, it was claimed that it would ruin the skyline of Paris.

[Shake]

Originally posted by jayh
NIMBY

Though in the interview with a newspaper reporter, the one experimental tower that is there now is barely visible from land.

There was strong resistance to the Eiffel tower, it was claimed that it would ruin the skyline of Paris. That's exactly what I was going to say. People want the benefits without any of the consequences.

There's a business in the next county east (I live in the city) which has recently put up a large windmill. According to the newspaper article, this guy generates about 30% of his electrical needs for his business. How many businesses would object to a 30% cut in their electrical overhead costs?

Also, I recently read about two local homeowners who each use a mix of solar and wind power for their power. They each invested $10,000 or less, but have no need for the power company to supply their electric. They even said how one of the couples still had many conveniences including a washing machine. One setup included a bank of 6V batteries like those used in golf carts for storage of excess power when consumption was low.

[Primordial Groove]

Originally posted by jayh
That's not free energy. It reduces gas mileage of the cars and increases pollution.

Not if they were put in at the off ramp positions. Vehicles exiting the freeway will be needing to slow their speed somehow.

[Thesto Neroses]

Originally posted by lpetrich
Because they can't stand the sight of them.

How foolish.

I think that wind farms are rather attractive. On my recent visit to Denmark, I happened to take this photograph - rather more appealing than a nuclear power plant or a coal fired monstrosity.

[Vorkosigan]

Me too, Thesto. And many locales with Windfarms report that they have become tourist attractions in their own right.

[jayh]

Originally posted by Thesto Neroses
How foolish.

I think that wind farms are rather attractive.

I have heard, and don't know how true it is, that they can be death traps for large numbers of birds because the animals don't comprehend the whirling blades. Do you have any information?

[Thesto Neroses]

Originally posted by jayh
I have heard, and don't know how true it is, that they can be death traps for large numbers of birds because the animals don't comprehend the whirling blades. Do you have any information?

A quick google found this document:
Rødsand Offshore Wind Farm
Environmental Impact Assessment
EIA - Summary Report (http://www.seas.dk/Upload/files/UserFiles/VVMResumeEngelsk.pdf)

Check out page 15 for a brief discussion of the possibility of bird collisions.

[Thesto Neroses]

More bird collision stuff:
Effects on birds of an offshore wind park at Horns Rev: Environmental impact assessment (http://www.hornsrev.dk/Miljoeforhold/miljoerapporter/Baggrundsrapport_18.pdf)

Check out page 70 of this report for more detailed information.Considering bird populations, collisions will act as an added source of mortality. This means that the potential impact of mortality through collision will vary with the population dynamics of the species. Species with a high reproductive output and a correspondingly low annual survival rate will be less sensitive to added mortality than species with a high annual survival rate and a low reproductive output.
Most of the species occurring in the wind park area belong to the
latter category.

Also, this page (http://www.hornsrev.dk/Engelsk/Miljoeforhold/uk-rapporter.htm) will give you many links to other environmental impact reports.

[Shake]

Originally posted by Thesto Neroses
How foolish.

I think that wind farms are rather attractive. On my recent visit to Denmark, I happened to take this photograph - rather more appealing than a nuclear power plant or a coal fired monstrosity. Right. I agree with you, but many Americans simply wouldn't like that. Or at least they'd say, "Why does that have to be visible from my shore? Couldn't they put them somewhere else?" I know it doesn't make sense, but I'm becoming convinced that most people aren't as rational as we'd like to think.

I think it might be a sort of American trait. It's like how we are about our cars. Many Americans understand why they should take public transportation, use renewable energy sources, etc., but they want the 'other guy' to start taking the bus, and using a windmill (so long as it's 'Not in my backyard!').