Yes, Bob, I meant that getting more energy out than is put in is a stretch. As for geo-thermal, it's a matter of harvesting energy that already exists. Whether it's practical and worthwhile, I don't know.
Rob, do you mean it's a stretch to get more heat or energy out than goes in? Having taken Theromdynamics 101 in enginering school, this claim is an obvious falsehood; however, the typical non-technical person might believe the manufacturer's statement. They put it in writing after all. In this forum of mainly technical people, we can only look at the claim with a wry smile.
On another subject regarding claims for "free" energy, I can remember 20-30 years ago when "geo-thermal" meant finding a place on earth where magma was close enough to the earth's surface that a liquid transfer medium could be pumped down through a pipe, then out after having its temperature significantly raised to obtain heat. The "heat" could either be used as heat or to make steam to run through a turbine/generator to make electricity. I believe some version of this has been used in Iceland for a couple decades. Now, "geo-thermal" is claimed by heat pump system manufacturers when they run refrigerent lines 6 feet underground taking advantage of the relatively constant ground temperature as a heat sink. "Geo-thermal?" That's a stretch!
The most recent device to be advertised the last couple years with more energy put out than put in is the so called "Amish Mantle". When one buys this wooden cover for several hundred dollars, he gets free a plug-in space heater "that actually puts out more heat than goes into it." How this occurs is not actually explained; but how many consumers have the knowledge and resources to verify this? Electric space heaters must be fairly popular because so many are sold. Their value is in keeping small space warm and cozy instead of heating the rest of the house to the same temperature. Since electric resistance heat is usually the most expensive heat to consume, its relative worth would have to be calculated against the cost of the whole house heating system.
Some 30 years ago, my mother actually invested in a similar "techno-scam". Some whiz-kid had allegedly invented a substitute for an external antenna for car radios. I asked her to get a copy of the technical description. What was described was, in actuality, a 3-electrode neon bulb (imagine an NE-2 with a third electrode). These were commercially-available components that could be described as a "soft, gaseous triac". Anyway, this device was to be placed inside the metal enclosure of the radio and serve as the antenna (claimed to work for AM and FM). Of course, this violates all that's known about antenna and electromagnetic waves. I told her she'd better get her money back before others discovered they were being bamboozled by this guy. Fortunately, she did ... and predictably, the others never saw their money again.
Sam finally has Bugs tied and standing on the edge of the platform, with Sam sawing away at the board, gloating: "Now ya smarty-pants, let's see ya get out-in this one! This time, you're a-diving!" However, as soon as Sam cuts through the board, it's the ladder and platform that falls, leaving the cut plank suspended in mid-air. Bugs turns to the camera and cracks: "I know this defies the law of gravity, but, you see, I never studied law!"
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