Howell
Storage? I am Storage!
Thanks to ddrueding I'm reading about physics to understand how much energy is required to spin a 20-ton mass object to 20K RPM in a vacuum. I never took any kind of physics so I'd like to learn how to calculate this. I have to assume zero friction for the rough estimate. With friction, would it just be like adding a fluctuating and variable weight to the mass? Then the friction will likely generate heat which would then change things ever so slightly over time. Maybe that heat from friction is exchanged through liquid and also used to reclaim energy since the energy going in is converted to both the spinning object mass and also friction based heat? Maybe the bearing is liquid cooled and that heat can be used for your house during the exchange process?
This should help you a little bit.
http://galileo.phys.virginia.edu/classes/635.stt.summer05/Manual/July 20/Rotational Dynamics.pdf
http://en.wikipedia.org/wiki/Rotation_around_a_fixed_axis
The topic you are looking for is rotational dynamics. To account for friction, either bearing or air, you add th effect of friction into the force equations.