15 MW Vestas wind turbine over 900 feet (300 m) tall

[dougselsam]

The world's most powerful turbine produces energy for the first time

This one is over 1/8 mile wide (span) and almost a quarter-mile high.

[Rodread]

There was a good video showing the Vestas build process in that article.
Here’s one explaining Musk company work processes / ethics / methods … Joe Justice, Wikispeed - Everyone Must Be a Chief Engineer at SpaceX | Iteration22 - YouTube
Which company would be a better AWES maker?

[dougselsam]

Chinese 18 MW turbine:

China’s CSSC Haizhuang unveils 18-MW mega-turbine

[PierreB]

V236-15.0 MW™

[PierreB]

China test for 30MW wind turbines as green power ‘arms race’ goes on

Chinese industrial group Sany claimed a new test facility is the first of its kind able to handle blades for 30MW wind turbines, in another sign that China is unlikely to call a halt to the industry’s ‘arms race’ over ever more powerful machines.

The group’s Sany Renewable Energy unit said a newly-commissioned dual-axis ground-based exciter, which simulates the forces facing blades in operation, can fatigue-test the 100-metre-plus blades now entering the market.

“This is the first integrated test for fatigue testing of ultra-long blades in China, satisfying the verification demands for blade performance of 30MW-class wind turbines,” said Sany RE, which earlier this year unveiled a 131-metre blade claimed to be the longest ever produced for onshore wind.

A LinkedIn post about this giant wind turbine:

Rosemary Barnes on LinkedIn: How much bigger will wind turbines get? —...

And also @ChristianH 's comment:

I’ve been trying to get this point across with airborne wind energy, our goal is to leverage the cubic relation ship of wind speed and power

See also:

How much bigger will wind turbines get? — Pardalote

[dougselsam]

This question of whether turbines could reasonably be built bigger has been in place for the entire duration of modern windfarms. It always seems that the limit has been reached, but then they become even bigger. I remember when a GE 1.5 MW turbine seemed so huge nobody could believe it. Now they are considered small.

[PierreB]

@dougselsam

And of course they never mention why most motors and generators are mounted with a horizontal axis, (which is the bearings are way happier when the weight is parallel to the plane of rotation of the rotor).

Hi Doug, this remark is really interesting and can only have been formulated by someone who actually knows the question. To be honest, I wouldn’t have thought of it, although in hindsight it seems obvious.

This may be an explanation for the unstoppable success of HAWT towards larger and larger sizes, which seem limitless.

[PierreB]

@dougselsam

Moving more air, at lower speed is more efficient than moving small amounts of air at high-speed.

This may be the reason why we are seeing wind turbines that are getting bigger and bigger and still have only one rotor, despite projects with multiple smaller rotors that have not really caught on.

[dougselsam]

I’m not so sure about that, Pierre. Wind turbines take whatever the wind provides. They don’t “decide” that smaller rotors would somehow have higher loading per unit swept area than larger rotors. I think the reasons are:

1. Bigger rotors enjoy a higher Reynolds number;
2. A single rotor has less possibility of destructive inter-rotor vibrations and oscillations;
3. The support structure for a rotor array would also suffer from a cube-square law, and might take up just as much total material as a larger, but disproportionately rotor.
4. More simplicity, fewer total moving parts;
5. A less cluttered and more aesthetically-pleasing appearance;
6. Industry inertia - “We’ve always done it this way.”