X-Message-Number: 33400 From: Date: Mon, 28 Feb 2011 16:53:23 -0500 (EST) Subject: long term free energy At CI the cost of energy is not a major expense and our cryostats do not rely on electric energy. Even so, there can be spurts of price of oil or anything else, and independence would be nice. Liquid nitrogen is not a major expense either, but it would be comforting to be able to generate our own without paying for energy. Several types of energy are potentially nearly unlimited in magnitude and eventually relatively cheap. But the outstanding candidate for the long term is Seebeck electric energy. The thermoelectric effects were discovered almost 300 years ago, and we consider a circuit with different materials on the two sides. If an electric voltage is applied across the circuit, one junction will become cooler and the other warmer, the Peltier effect, which can be used e.g. for refrigeration (or heating) with no moving parts. The reverse is the Seebeck effect--use of a temperature difference to produce a voltage. (When Mae and I lived in Arizona, our house used thermo-electric heating and cooling.) What makes Seebeck electric energy outstanding, compared say to solar or tidal or wind energy, is that it is available always and everywhere, not just when the sun is shining or the tide is changing or the wind blowing. A Seebeck generator requires only a temperature difference between two nearby locations, and these always exist--e.g. surface and subsurface temperature differences always exist, on land or at sea, although of course some will be more attractive than others. A simple Seebeck circuit, using temperature difference to measure voltage, is called a thermocouple. A bunch of thermocouples in series is a thermopile, the voltages additive.. Once built, a thermopile has no maintenance cost, since it has no moving parts, and after you pay for the gadget your energy is free. (I'll omit some very minor quibbles.) So far the capital cost is not in the competitive range, but it will get there. Robert Ettinger Content-Type: text/html; charset="US-ASCII" [ AUTOMATICALLY SKIPPING HTML ENCODING! ] Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=33400