Posted by small energy on January 10, 2010, 8:02 am
Germany and Alabama did not think compressed air energy storage is a
waste of time. They are the only places that use it on large scale. I
believe it can be used on the small scale for residential backup
power. If compressed air is at high pressure it can be used to push
liquid from one tank to another and turning a generator on the way. If
the air is recaptured then the only thing used from it was the energy
stored in it. Air pressure multipliers are available. One is shown at
www.myspace.com/gdhenderson . You use low pressure air to get high
pressure air for storage. High pressure air is regulated for use. High
pressure air is used for transportation in Air car and air powered
scooters. It is also used for residential backup power in UK. See
www.energetixgroup.com/pnupower/html/ . There are many ways to get low
pressure air. Air is also very environmentally friendly. Affordable
backup power supplies are not meant to replace your existing service.
It is nice to have a backup when your existing service has a problem.
Posted by vaughn on January 10, 2010, 2:54 pm
Tue, but it is a non-starter for residential use. For a variety of
reasons,.your storage costs would be very high compared to batteries and your
efficiency would be far lower than with batteries. (mechanical losses in the
compressor & turbine, combined with thermal losses associated with the expansion
& compression of gasses.)
How would this be better than just using an air-driven turbine?
Last I heard, there is no shortage of air.
Which will help with storage density, but only at the expense of multiplying
your mechanical and thermal losses.
Show us one that you can actually buy please.
Nope, you are making the classic error of mistaking a UPS for backup power. A
UPS is only intended to keep equipment going through a SHORT TERM power failure
or to allow your REAL backup power source to be started and put online, or to
allow an orderly equipment shutdown.
Please name a few.
True, we all need it. :-) ...but the source of energy to compress the air is
not necessarily environmentally friendly.
Very true. A UPS is not backup power. For that you need either a generator or
a substantial battery storage system with PV or wind recharging, or both.
Also very true, but yours is unlikely to ever be air powered.
Posted by Jim Wilkins on January 10, 2010, 3:11 pm
You need to calculate te energy density and the efficiency of
compressing and using it. The 60 gallon tank on my compressor, pumped
to 120PSI and applied to an air tool, does about as much work as one
cent worth of electricity in a similar electric tool. For the electric
tool that's 800W for 5 minutes, the air tool is harder to figure
because its effect drops with pressure but they'll grind similar
amounts of steel off a weld.