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UNLIMITED RECYCLING OF HEAT ENERGY UNLIMITED RECYCLING OF on the molecular scale, the scale of one- HEAT ENERGY tenth of a nanometre. If we go about 100 by Martin Gottschall, PhD © 1998 times higher, to a scale of about 10 nanometres (nm), the quantum restriction is r “Nhis paper gives a brief description of 100 times weaker—and Maxwell's demon a device which the author believes _ is there, waiting to be put to use. can convert heat into electrical ener- The principles on which this proposal is gy in an unlimited way. based were discovered by the author in The conversion of heat into mechanical, about 1960. A paper based on these was electrical and other forms of energy has — submitted to the journal Nature in 1972. been found to be governed by certain limi- At the same time, about 20 copies with tations which have been embodied in what accompanying letters were sent to a selec- is now known as the Second Law of _ tion of national embassies. The writer Thermodynamics. It is generally held that believed that the proposal had a good all possible processes that convert heat to chance of being practical, and governments other forms of energy are subject to this should be forewarned so that the new tech- law, although not all of them have yet been nology could be brought into use without tested. undue dislocation and so that existing ener- Over the decades, many inventions have — gy technologies could be adapted. The been put forward for which it has been submission was rejected, and the technolo- claimed or implied that the second law _ gy has clearly not yet come into public use. does not apply. In many cases the inven- Since 1972 there has been much progress tors unknowingly used the very processes in small-scale technology, particularly in on which this law is based, and so their — what we call "nanotechnology". Perhaps inventions had to fail. this time, people with the necessary skills James Clerk Maxwell contributed to our and resources will recognise the potential understanding of heat, and must have in this device and commit themselves to its reflected on the inner workings of the sec- development. ond law because he invented what we now call "Maxwell's demon", an imaginary enti- ELECTROSTATIC GENERATOR ty which can sort the molecules of a gas The device works with heat energy on a into a high- and a low-energy collection, scale of about 10 nm, and the "demon" is thereby overcoming the second law by creating a hot and cool as body without expending a g y P & 7 7 777, significant amount of energy. Maxwell's solution was on the PLATE - B atomic and molecular scale. / f/f ZL Z With the development of quan- tum theory in the first third of 4 + this century, scientists found that Maxwell's demon would need energy to do his sorting after all, because he needed energy (light) by which to see, and this energy expended could exceed the gains \ \ achieved. Thus it seemed that PLATE-A the second law had triumphed on : the molecular scale as well. VA NA \ In the author's view, this con- . : clusion might have been a touch Figure 1: An electrostatic generator base hasty. We do not have to operate "contact potential". Metals are a class of substance in which the naturally occurring charges (electrons) that surround every atom are free to move about within the sub- stance. This makes metals electrical con- ductors. Non-metals have their electrons bound to atoms or molecules, and they exhibit little or no electrical conductivity. Although electrons may move freely within a metal, they cannot readily escape into the space around the metal. For each metal, a certain amount of energy is needed to lift the electron into the surrounding space. Different metals require different amounts of energy for this. When two dif- ferent metals touch, the metal having the greater attraction for electrons will attract electrons from the other metal and become negatively charged, and the voltage associ- ated with this charge eventually stops the flow of electrons. This voltage is known as the "contact potential" of that metal pair. Figure 1 shows an electrostatic generator based on contact potential. Small metal balls are confined to the space between two metal plates A and B. When the balls touch plate A, they acquire one excess electron because of contact potential. When they touch plate B, they give up any excess electrons they may possess, as well as one extra electron—which leaves them electron-deficient or positively charged. If ELECTROSTATIC GENERATOR The device works with heat energy on a scale of about 10 nm, and the "demon" is JUNE - JULY 1998 NEXUS - 51 by Martin Gottschall, PhD © 1998