To Store Renewable Energy, Try Freezing Air
You might get away with pissing on Carnot&#x27;s grave once - but twice - never. By that I mean the energy of compression is lost. A compressor is an analog to an internal combustion engine - in reverse. You put in energy via amotor and compress the air. Unless you can use that heat of compression it is lost. Then you run another analog to an internal combustion engine - in reverse.
<a href="https:&#x2F;&#x2F;www.google.com&#x2F;search?ei=jFgWXoCkI474-gTJspPoDQ&amp;q=energy+efficiency+of+an+air+compressor&amp;oq=energy+efficiency+of+an+air+compressor&amp;gs_l=psy-ab.12...4691.7128..9727...0.2..0.100.661.5j2......0....1..gws-wiz.......0i71j0i13j0i13i5i30.PGxHy-B_CRo&amp;ved=0ahUKEwiAmpzFh_XmAhUOvJ4KHUnZBN0Q4dUDCAs" rel="nofollow">https:&#x2F;&#x2F;www.google.com&#x2F;search?ei=jFgWXoCkI474-gTJspPoDQ&amp;q=en...</a>
Extract:-
• Is compressed air free?
No, compressed air is not free.  Although &quot;it&#x27;s only air,&quot; compressed air is actually very expensive because only 10 to 20 percent of the electric energy input reaches the point of end-use.  The remaining input energy converts to wasted heat or is lost through leakage.  For example, to generate 5 CFM it takes 1 HP.<p>So 10-20% for the compressor.<p>Then the expansion:-
<a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Pneumatic_motor" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Pneumatic_motor</a><p>sir motors are in the 60-65% efficiency range.
Then the electric motor to drive the generator is about 93% efficient (some as high as 95%)<p>This string of 10-20% plus 60-65% plus 93.95%<p>Gives a net range of 5.58% efficient all at low end of range   to about  12.35% at the high end.
At best you lose 87% and at worst you lose 94.5%<p>But this is wasted energy anyway, but it has to pay for manitanance and staff etc, so in the worst case it is terrible and the best case is sub-marinal.
Looks like a free energy racket to me?