A consequence of the Second Law of Thermodynamics is that no isolated process may exist in which a result is an increase in exergy. This is commonly known as the exergy destruction principle and is analogous to the entropy increase principle. The reason for this is quite simple and logical. A process that would serve to produce work, transfer heat, etc. and have the converted energy at a higher quality than initially would suggest that that energy could now do more work than it could initially. Such a system could essentially perpetuate work potential (or energy) making the lords of thermodynamics very angry by violating the first law as well as the second.

For a better understanding consider beer. In pouring a beer one experiences an unwanted increase in the entropy of the fluid as well as an unwanted decrease in its exergy in the form of head. We can only really theorize a beer pouring process that produces no head since in fact all pours maintain some level of irreversibility as head. Essentially we experience an increase in the entropy of the fluid (represented here by the head) and a decrease in the exergy of the fluid (the actually non-head beer). Since head actually contains less mass than beer, and thus less alcohol, the work potential of your glass of beer has decreased since it contains less alcohol than the volume of the glass would otherwise allow. Thus you're glass has more stuff you don't want (entropy) and less stuff you do (drunk potential, i.e. alcohol). Thankfully science has afforded us numerous ways to increase our second law efficiency when pouring a glass of beer. Patience and tilting allow for greater exergy recovery than pouring from heights or drinking hastily. The work potential of your alcohol could also be increased by substituting your working fluid for tequila or rubbing alcohol of which some is bound to vaporize when pouring (increase in entropy, decrease in exergy) but whose second law efficiency is bound to be greater. Drinking in very cold places could help in this respect but would cause the body to shiver causing the alcohol itself to metabolize faster. Changing the working fluid to ingestable drugs like GHB would also help though one of the best ways to ensure high second law drinking efficiency would be not to drink at all, intravenous inebriation is much more efficient (close to 100%).

Just remember that intoxication is not internally or externally reversible, and unfortunately neither are the scores of bad decisions and morning after remorses, even with a second law efficiency of 100%.

Log in or register to write something here or to contact authors.