At 4:54 AM 2/16/5, Frederick Sparber wrote: >A little pencil work: > >The heat of vaporization of liquid air is 88 Btu/lb (86 Btu/lb for LN2) >at 2546 Btu/hp-hr. >At 25% overall thermal efficiency (~10,000 Btu/Hp-Hr) 120 lbs of LN2 would >have to be carried to deliver that 1.0 Hp-Hr. > >LN2 at $.10/lb would cost you $12.00/Hp-Hr. :-)
LN2 is not very good, but it is (wow! there is an earthquake going on right now! Feels like a 4 or 5 magnetude) a little better than that. Only 35 percent, about 200 kJ/kg = 88 Btu/lb is heat of vaporization, the rest of the 570 kJ/kg is from gas expansion which can be captured by turbine. Regards, Horace Heffner
