“In all energy exchanges, if no energy enters or leaves the system, the potential energy of the state will always be less than that of the initial state.”
In simpler terms, the Second Law of Thermodynamics states that heat always flows from the hotter object to the cooler object until they’re equal and a state of thermal equilibrium is reached. Heat can’t flow by itself from a colder to a warmer object … except perhaps in Zurich.
“At first sight, the experiments appear to be a kind of thermodynamic magic, thereby challenging to some extent our traditional perceptions of the flow of heat.”
The traditional flow of heat is from hot to cold
Researchers from the University of Zurich announced this week that they seem to have broken the Second Law of Thermodynamics with a simple heat pump device known as a Peltier element. Using it as a kind of thermodynamic magic wand, Prof. Andreas Schilling of the Department of Physics at the University of Zurich announced in a news release that he and his team cooled a nine-gram piece of copper from over 100°C to significantly below room temperature without an external power supply.
“Theoretically, this experimental device could turn boiling water to ice, without using any energy.”
Is this a Tesla moment? Only if the process can withstand the heat (or is it now cold?) of a closer analysis. Peltier elements normally use energy to reduce temperature and can be found in camping and portable coolers, heat sinks for microprocessors, climate-controlled clothing and hotel minibars. Since a Peltier device (also called a thermoelectric cooler, solid state refrigerator or Peltier heat pump) have no moving parts, they last longer without no need for maintenance. On the downside, they can only be used for small applications since they can generate only a small state of heat/cold flux. Of course, the ability to do this without using any energy whatsoever would change everything … if it weren’t for that Second Law.
“The researchers have now shown for the first time that this kind of thermal oscillating circuit can also be operated “passively”, i.e. with no external power supply. Thermal oscillations still occurred and, after a while, heat flowed directly from the colder copper to a warmer heat bath with a temperature of 22°C, without being temporarily transformed into another form of energy.”
“Heat flowed directly from the colder copper to a warmer heat bath.” That sounds like a law-breaking action, doesn’t it?
“Despite this, the authors were also able to show that the process does not actually contradict any laws of physics. To prove it, they considered the change in entropy of the whole system and showed that it increased with time – fully in accordance with the second law of thermodynamics.”
That may change. Schilling says that in theory, a perfect Peltier element could cool up to -47°C. under the same conditions were the “ideal” Peltier element to be used. Unfortunately, such an element has yet to be created. When that happens …
“… large amounts of hot solid, liquid or gaseous materials could be cooled to well below room temperature without any energy consumption.”
Would that be a violation of the Second Law of Thermodynamics? It sure sounds like it. It wil be worth it because cooling without using a refrigerant or energy will reduce carbon emissions and help reverse climate change.
Will a no-energy minibar fridge lower hotel bills? Probably not.
Paul Seaburn (CLICK HERE TO READ AND SEE MORE)
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