ENTROPY

We usually think of energy as the capacity to do work. But not all of a given amount of energy can be turned into useful work; there always remains an unusable amount of inconvertible heat. Heat is somewhat different from other forms of energy. Mechanical, chemical, electrical or other non-thermal energy can be totally converted to heat down to the last microjoule. But conversely, not all of a BTU of heat can be converted to, say, mechanical energy. At best -- and not even that can be quite achieved in practice¾one can extract only as much as corresponds to the difference in temperatures between the heat carrier and the environment. Suppose, for example, you have warm water at 100 degrees F in the Arctic; then you can boil ether and run a turbine with its vapor, which will exit into the arctic cold as it leaves the turbine. But the same warm water will do no work on a tropical island where the temperature is 100 degrees F everywhere, in or out of the turbine. There is nothing to make the vapor go through the turbine: temperature differences for heat are, in a way, what height differences are for gravity. But not even in the Arctic can all of the heat of the warm water be turned into mechanical work; a part of it remains inextractable and therefore unusable. How much? That depends on a quantity called entropy which can easily be calculated, and which determines (though it does not directly equal) the unusable part of the heat in a closed system. The turbine could be used to drive a generator to provide electric light. But at each conversion some more energy is irretrievably lost as heat (e.g., in the bearings of the turbine), so that the entropy, the measure of this uselessly lost energy, keeps increasing. It is, in fact, a law of physics that the entropy in a closed system keeps growing ("tends to a maximum"), for more and more heat, and less and less of the other energy forms, must result if each conversion extracts its unrefundable little toll of heat.

He cannot, of course, beat the law of increasing entropy; but the entropy can be increased elsewhere¾by the ships that bring the fuel, by the sun that made it. For now usable energy¾genuine capacity to do work¾is brought into the system from outside. He has increased both energy and order in his neighborhood by making the law of entropy increase disorder (irretrievable heat) far away from his immediate environment. Pushing off the inescapable increase in entropy to other places, he has gained negentropy (negative entropy, higher-grade energy) for himself. He did not have to study thermodynamics to accomplish this; he just used common sense. And a polar bear survives in the Arctic merely by being alive. For life, as Nobel Prize winner and quantum mechanics pioneer Erwin Schrodinger said in 1943, is the capability of extracting negentropy from the environment. An organism organizes itself by increasing the entropy of its environment rather than its own, attaining states that would be "improbable" if they came about "of themselves" in inanimate matter. When an organism dies, it loses that capability; it becomes inanimate matter incapable of pushing off the laws of entropy to the outside world. CONSERVATION The basic laws of thermodynamics were discovered in the last century; some fundamental ones by Josiah Willard Gibbs (1839-1903), who in 1863 gained the first Yale Ph.D. awarded for an engineering thesis. His private means enabled him to accept the appointment of Yale Professor of Mathematical Physics, for in those days the appointment was unsalaried. The laws of thermodynamics rank among the most brilliant monuments to human intellect, and it is ironic that they should be abused to camouflage the shallow prattle by social engineers like ex-scientist Commoner and non-scientist Lovins. What, for example, do you gain when you don't build a dam on a river? Some kinetic energy of the water is changed to heat and the entropy of the universe is raised a little.

The Lovins disciple below, for example, has a significantly higher second-law efficiency than if like the rest of us energy pigs, he used an electric drill. Moreover, these energy scholars ignore the energy that goes into the manufacture of their gadgets. Prof. F. Cap has recently given a short mathematical proof that the worst possible use of extractable energy is to waste it on the manufacture of facilities that turn high-grade energy into heat at low temperatures¾that is, solar collectors. A book by Prof. Klaus Knizia, just published (but unfortunately also in German) makes the same point by non-mathematical reasoning. "If we strive for a maximum of life quality with a minimum destruction of the ordered states of the environment, then our task must be to extract a maximum of negentropy from a given energy flux... It is, on the other hand, wasting energy to channel large amounts of negentropy into facilities of so-called 'soft technology,' which will not give us a sufficiently great return of energy [extractable energy] to justify the investment of energy and raw materials in their construction."