The use of liquid air as a "motor fuel" gets more attractive when one
considers that a Carnot efficiency of 65% - 75% between minus 50 (410 R) and 120 deg F
(580 R) and a mechanical efficiency of 50% (~ 15 watts/Lb) is competitive with
state-of-the-art lead-acid storage batteries rated at 15 watts/pound.
Liquid air properties:
Boiling point 142 deg R
Heat of vaporization 88 BTU/Lb
Hybridization with LN2 superconductors and flywheel technology is also a possibility,
Cheap summer air-conditioning as part of the power cycle is thrown in as a bonus.
Compact "home air liquefaction" units could be used at costs comparable to
battery recharge.
I can't see how "transportation hydrogen" can beat it.
Frederick
