Намерих и малко цифри. Процента на спечелена енергия при кондензацията е между 10 и 30.
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Condensate contains a significant amount of sensible heat that can account for about 10% to 30% of the initial heat energy contained in the steam.
от тук: http://www.tlv.com/global/TI/steam-t...-recovery.html

Figure 14.1.5 compares the amount of energy in a kilogram of steam and condensate at the same pressure. The percentage of energy in condensate to that in steam can vary from 18% at 1 bar g to 30% at 14 bar g; clearly the liquid condensate is worth reclaiming.
от тук: http://www2.spiraxsarco.com/resource...e-recovery.asp

П.С. Още нещо интересно: http://www.explainthatstuff.com/heat...ntilation.html