> > For me in 2002, the idea was to build a house in the 
> western desert of 
> > the US, self-sufficient, with wind generator and batteries 
> for light 
> > storage, and use compressed air for long-term storage. For 
> safety, the 
> > compressed air tanks had to be buried deeply underground. 
> The reason 
> > is that in the US Western desert, wind speeds are high for several 
> > months of the year, then low for several months, and excess 
> wind power 
> > would run compressors to store excess power. I think it is feasible 
> > for a house, but NOT feasible for a vehicle, because
> > (1) an accident could result in a disastrous explosion, and
> > (2) extra weight would be needed to make the tanks strong enough to 
> > withstand 2000psi+..
> 
> 
> Compressed air has a lot of power but not much energy, high 
> volts but low amps, you might say.
> 
> Can you claim the fishing method as environmentally friendly?
> 
> They is/was a company making flywheels to store energy for 
> houses, you dug a hole & dropped it in there.  They were 
> targetting them at businesses to use as back up power, 
> replacing petrol generators & UPS batteries.
> 
> Fairly safe, if the flywheel exploded, well, it's in a hole 
> in the ground.
> They were in a low pressure (maybe a vacuum) container with 
> magnetic bearing, so 'self discharge' was low.  Not a bad 
> idea if you can get it to work.  Would last a long time too, 
> not much to wear out.
> 
> Tony


Interesting, Google found not only people selling them, but people buying
them.  Doesn't seem to be the 'hole in the ground' ones.

http://www.pentadyne.com/spec_vssdc_plus.htm, claims 60kW load for 45
seconds.  That should power your house for, oh, 20 minutes or more.  Big &
heavy too.  Lasts over 20 years.  99.8% efficency?

http://www.powerware.com/UPS/PF2_Flywheel_specs.asp, lots of versions.  I
wonder if they just change the flywheel mass...

Wonder what they cost?  Anyone got one in the basement?

Tony

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