FlyWheel Energy Storage

First, avoid contacting the nonexperts. This will narrow your search considerably.

Lol!!! I agree.

This topic is a pretty uncharted area however there was a posting on this about a couple weeks ago showing one such power new plant in the US.

I remember that. It seems that people were afraid of noise, which makes little sense. If there were any defect in a fast-spinning flywheel that made it fly apart, the underground location would solve that. I mentioned Foucault type effects that might result if the flywheel axis were skew to the earth's axis. I don't know if that would be a huge problem, but it would put unnecessary stress on the bearing system.

Consider also the Coriolis effects since the flywheel will behave as gyroscope.

I was going to suggest a message in a bottle...but common sense and your suggestion stopped me.
Del

My suggestion is not to use a flywheel to store energy. In a thesis I read by Travis Painter for his Masters in Civil Engineering he suggests using them to store energy from locomotives dynamic braking. If I cannot link this properly, google Travis Painter Thesis and it should come up as a pdf as one of the top results.

http://www.google.com/url?sa=t&source=web&ct=res&cd=2&ved=0CBcQFjAB&url=http%3A%2F%2Fciteseerx.ist.psu.edu%2Fviewdoc%2Fdownload%3Fdoi%3D10.1.1.125.9656%26rep%3Drep1%26type%3Dpdf&ei=Tf_nS-CTJ4mqNsigtYcF&usg=AFQjCNF8vhNXV5bDL0YSEySLLhFXOAPt6Q

Wow, that is ugly, but is what came up when I copied link location. It is a huge document and he doesn't get into flywheels till half way down or so. Toward the end when he is writing about efficiency he states something like 70% losses going to and from the flywheel.

My recommendation is to find a better way to store energy, if it is a small amount, use a clockwork and weight, if it is alot, try to find users for it and dont store it.

Drew

Underground Flywheels for Energy Storage

This may help.

There are several manufacturers of rotary UPS's, Pillar, Caterpillar, there are others, they use a flywheel instead of batteries to store energy to be discharged in the event of a power loss, they have a limited duration, usually more than enough time to bring a genset on line

This seems correct. You can put energy into a flywheel, but if you let it spin for a week, it will slow down enough to degrade the efficiency. I would estimate that flywheels would be useful for storing/releasing energy over a span of a few hours. In other words, good for daily fluctuations in demand, but virtually useless for summer/winter variations.

It all depends on the friction losses thus on the design of the bearings and the degree of vacuum in the box where the rotor spins. Of course also the induction losses have to be considered (histeresis in the magnetic circuits).