On 2009-03-11, Leo Lichtman wrote:

"Ignoramus26567" wrote: (clip) This is because compressing air to higher
pressure heats air more than
compressing air to lower pressure, and that heat is completely wasted
(clip)
^^^^^^^^^^^^^^^^^^^^^^
Dropping the pressure to a lower value through a throttling valve or
regulator wastes the energy that could have been obtained by running it
through an air motor to lower the pressure. So you lose on the way up and
you lose on the way down.

Great point.
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