If you're thinking of a direct mechanical linkage, you wouldn't want to put it up on the tower because the mass to effectively store megawatt-scale power is way more than you'd want to support up high. Also, since the wind blade usually swivels to the wind, you'd want to avoid the rotational inertia. So, you'd need a mechanical linkage to transmit the power to the ground, maybe installing it under the tower base.
You would not want to use a direct mechanical attachment, i.e., resembling a combustion engine - transmission flywheel, because this would impair the ability of the wind turbine to start. Generally, turbines are designed for minimum inertia to easily start in low-wind conditions. A direct connection would impede that.
Now, we're adding a clutch-sort of mechanism, and that has its own additional complexity, weight, and energy.
Moreover, considering that we're trying to store megawatt-scale energies, we are at a large mass spinning very fast, and probably spun up with an electric motor.
So, it would seem the best way to do that would be to make a flywheel farm, with the flywheels below ground to contain failures. At this point, why locate it in the probably inconvenient location where the wind turbines are located, and instead put it somewhere more convenient, such as nearer to the consumption areas?
I'm not sure how that would help? If you had a flywheel and you didn't need the energy, what do you do with it? At least without a flywheel, you can easily stop the turbine.
Also, any flywheel that would add significant difference would probably weigh hundreds of tonnes, which would make construction massively more expensive and difficult.
If you don't need the energy you just let the flywheel spin freely. It's a mechanical battery. I agree with your second point though- it would add considerable mass to the hub assembly of the wind turbine and there is no clear way to transmit the mechanical energy to ground level.
Yes, except with several orders of magnitude more energy and rotating mass.
Wind turbine blades are engineered for minimum mass and inertia, are manufactured primarily from fiberglass and/or carbon fiber, are hollow, and the largest mass is in the center.
In contrast, flywheels are engineered for the highest practical inertia, are manufactured from the highest density material that works, and concentrate that mass as far out as possible.
When a wind blade fails catastrophically, it makes a mess of splinters right around the tower, as shown in [0] and [1].
In contrast, just a small automotive flywheel explosion, contained in a legally mandated scattershield, is almost as spectacular [2], [3]. Now, magnify that from a flywheel just designed to smooth the power from a 375kW (500HP) engine to the scale of a flywheel to STORE the energy of a megawatt-scale wind turbine.
So, no, the danger of a megawatt-scale energy storage flywheel is NOT like the danger of a "giant rotating wind turbine".
Ha! Interesting, I had noticed the horses seemed off. In the comments it looks like the author was playing with CGI and modeled it on the Dutch failure video. I'd obviously just posted results of a quick search for short vids.
i agree, wind turbines do rotate but not at high speeds, disintegration of one doesn’t lead to catastrophic outcomes. Flywheels on the other hand are meant to rotate at high speeds and hold lots of energy, so destruction of the spindle would lead to some pretty big bad results
