1/17/2006: Horizontal windmill

It took a French-to-English translation of the full story for me to comprehend what this is. It's the first horizontal windmill in France, they say. First one I've ever seen, too.

They're putting on top of a building where it will generate 9000 kW/h -- they don't say whether that's in top gear, or an average. Well, nothing else is going on, on top of most buildings, so why not take advantage and generate a bit of juice.

One interesting thought. The mill is one of the earliest ways that humanity captured energy for its own purposes. Designs for different types of mills are some of the earliest hard core engineering ever done. A tremendous amount of thought went into designing and building the things, over centuries of time. And yet, here is an innovation that only recently happened, due to the need to take advantage of different space with different demands.

There are always new things in the world, you know?

Hope that roof is not accessible to anyone while they're on.
They look fastrotating. So watch your heads guys...

let's hope a bird doesn't get sucked into a wind current up there...

nine-thousand? that's a lot of lightbulbs...

I think that design will allow it to work with the wind coming from any direction. So it won't need to be able to turn on a vertical axis.

i want one, that's damn cool.

9000 kW/h... how much power is that compared to say... a regular generator and a regular windmill?

I have no concept of units of electricity. So I tried to Google it to get some idea of how much power we are talking about. According to this, the average household electric power demand in the US in 1997 was 10,219 kWh. So that's roughly what a typical house runs on in a year.

If this thing generates almost that much in an hour, then I'm floored. It just seems impossible to me. What am I missing? It's too good to be true.

Is it just me, or could that beat one huge egg?

A few years ago I saw a design for a giant flying one of these. It would fly like a kite, with the powerline doubling as the string to hold the kite in place. It had a generator/motor at each end of the axis. To get it up in the air, power was fed to it and the motors turned it and it flew itself up. Once it was at maximum altitude (really high, in the jet-stream) it would then get turned by the wind and the motors would become generators and it would send power back down to the ground. It could stay up for days or weeks at a time because the wind in the jet-stream is fast and steady. It would only need to be winched back down to ground if a storm was approaching (the generators could be made to work as motors again to power a safe landing).

Good chance of putting the $ grubbing power co-ops on their greedy asses.

Prolly cost a fortune to own one.

I bet Howard Hughes would say it's "the way of the future". I think it will wind up on the bench with the 200 mpg carburetors.

From the link via babelfish;

I saw the vertical eggbeater versions in a demonstration in 1976. The company claimed they were more efficeint than the propeller design, but all I see are the propeller style windmills, so something must be driving the selection.

BTW, the kite idea sounds interesting, but if enough people did it I could imagine a real hazard to airplanes. It would be like having barrage balloons in WWI and WWII.

I hope they fence the things off so that some mad Don Quixote doesn't get batted off the top of the building.

it slices, it dices, the RonCo Wind-O-Matic!!

Does anyone else want to just throw a huge eggplant through that thing when it is in a gale?

A few months back I was doing some work a a state scale here in Arkansas , there were all these trucks carryoin these MASSIVE pieces , some looked like propellers , others just looked like BIG ass poles , the props were so big they took up an ENTIRE 18 wheeler , and the poles were in sections , i was woundering what they all were for untill i start seeing central hubs , a trooper pulled one of these truck over and asked what they were hauling , they were BIG ass wind mills for some where up north ( Michigan I think )

Growing up in the middle of California, we'd occasionally take trips over to the coast, in or near the San Fransisco bay area. On the way there, there were hills covered with tons of windmills of different designs. I always thought it was strange, though, usually when we drove past only certain ones would be moving. But what I recall most about the egg beater type windmills is that none of them were ever spinning. I kind of suspect maybe they need a lot more wind to get started than an ordinary windmill.

Either that, or they just locked some of them down so they wouldn't spin to make the ones that were running more efficient...

This eggbeater design is known as a Darrieus wind turbine .. named after its French inventor, who thought it up around 1927 ..

The interesting part about this design .. and linknoid has just touched on it .. is that the blades are built around an airfoil principle, and cannot self start - but must be cranked to get going.

Once running, they are more efficient than the regular propeller design, due to the airfoil design providing "lift" just like an airplanes wing.

Likewise, they have a lower velocity of the outer part of the blades, at speed .. unlike propellor designs, whereby the high speed of the prop tips starts to create drag at high rotational speeds .. as well as increased noise.

The Darrieus designs do have a problem with sinusoidal (pulsing) of the blades .. meaning at certain RPM's, they develop a "whip", which can break the blades if left at the critical RPM for too long.

This is a similar problem to the longitudinal whip which can develop in an internal combustion engine crankshaft, which can also break the crankshaft. Torsional dampers on IC engines help prevent crankshaft whip .. but they do not appear to be feasible with Darrieus turbine blades, because torque on the turbine blades is not a factor in the problem, unlike crankshafts.

The interesting part of the particular Darrieus wind turbine, pictured, is that they have crossed the design with a propellor design, by lying it down, and effectively turning it into a "horizontal axis" machine .. whereas most Darrieus arrangements are "vertical axis" generators.
By doing so, they have eliminated a major amount of cost, by not having to have, a massive base structure, bearing and guy wires.

The normal Darrieus vertical axis generators, although not needing a heavily-built tower for support .. are stuck with the problem of needing guy wires for support .. and the problem of needing to be nearly totally dismantled for any bearing or generator repairs.

To add complexity to interest .. high buildings generate substantial vertical wind currents .. and this particular turbine design above, appears to be following a Dutch design, known as the "Turby" design, which has blades with a helical cant, to take advantage of vertical air currents, as well as horizontal ones ..

More on wind turbine designs .. http://en.wikipedia.org/wiki/Darrieus_wind_turbine

I trust the "Turby" turbine design, performs far better than their website .. http://www.turby.nl/

Windwall is the Dutch company that installed the French unit pictured, and their website is quite informative ..

http://www.windwall.nl/eng/aboutwind02_eng.htm

Here is an another image of one on a building.

I bet the blades ice up bad. I would think they'd have to be maticulously balanced to work right. Wouln't take much ice to buffalo it prolly.

Teflon coat 'em.

Is that what they do to airplane wings?

No, they use heaters but that wouldn't be practical here.