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active heat wire

series of peltier devices moves heat along "wire"
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A series of Peltier devices each moving the heat through a small gradient in temperature so that total affect is constant heat flow in a certain direction (presumably out, for cooling)

Useful for cooling inner rooms, cars and what not.

Perhaps aluminum or copper wiring may be set between the stacked peltier devices, setting them at a distance from each other where the small temperature change is still effective.

Connected to solar panels, this could be quite a powerful device.

pashute, May 26 2015

Flexible Heat Pipe http://www.thermaco...ducts/flexible.aspx
[MechE, Jun 15 2015]

[link]






       (marked-for-tagline)   

       " Connected to solar panels, this could be quite a powerful device "
normzone, May 26 2015
  

       So the proposal is for a stack of Peltiers, longer (ie,in the direction of heat transfer) than it is wide?   

       I think you'll have problems due to the inefficiency of the Peltiers - they generate a fair amount of heat themselves. So your net result will be to warm up the hot end a lot, and to cool down the cool end by only a small amount.   

       As an example, a single Peltier might (depending on its rating) produce a cold-side temperature of -30°C at a push, but it will be belting out a lot of heat on the hot side. Stacking two Peltiers doesn't get you down to -60°C (more like -35 or -40°C).
MaxwellBuchanan, May 26 2015
  

       heat pipe: skip the multiple peltiers in the middle
FlyingToaster, May 26 2015
  

       There is also the problem of power supply. You either wire them up in series, where a stack of 30 will have you over 300V in supply, or you wire them up in parallel and you have to move a lot of current through thick wires with the potential of heat issues.   

       Much better to shift the heat with a heatpipe.
bs0u0155, May 26 2015
  

       Agreed - what [pashute] is proposing is, in fact, an elaborate means of encouraging heat to do what it would do anyway, only less efficiently.
MaxwellBuchanan, May 26 2015
  

       //encouraging heat to do what it would do anyway, only less efficiently//   

       A lot of fun could be described this way. For example, you can just burn scotch. Much faster than drinking it.
bs0u0155, May 26 2015
  

       [Edited the idea]   

       The idea is that each peltier only needs to move the heat down a very small temperature gradient. So a small voltage and current is needed, and not as Maxwell calculated.   

       A plus and minus copper wire will supply the current in parallel. Not something unusual.   

       I am not aware of a flexible thin wire that can lead heat out of a location. Instead there exist pneumatic air- conditioning pressurized gas pipes, large air ducts, or coolant liquid leading pipes, with thick insulation around them.
pashute, May 26 2015
  

       // [This] is, in fact, an elaborate means of encouraging heat to do what it would do anyway, only less efficiently. //   

       [marked-for-tagline] because, as [bs0u0155] said, it applies to just about anything.   

       // The idea is that each peltier only needs to move the heat down a very small temperature gradient. So a small voltage and current is needed, and not as Maxwell calculated. //   

       FOR EACH ONE. There's no getting around energy/power requirements.   

       // A plus and minus copper wire will supply the current in parallel. Not something unusual. //   

       Those wires will be very thick. Better to go with the series configuration and give it a high voltage. You can still use just two wires, one of which is your Peltier wire.
notexactly, Jun 07 2015
  

       In air conditioning you use thick insulated gas pipes, and then a very large pump and fan.   

       The Peltier "wire" will be like a thick electric cable no more. Which makes it much more flexible.   

       "There's no getting around energy/power requirements". Of course not, but they are the same energy/power requirements as those for a standard air conditioner system. Its mostly a question of different configuration (granted: being less efficient, means it would do less cooling).   

       BTW - I once saw a Dutch company that advertised a "gradual" cooling system that worked on continuous cooling of the house day and night rather than the on/off ad-hoc cooling. I'll try to find a link to it. They claimed their analysis showed that they actually saved a lot of energy.
pashute, Jun 09 2015
  

       "magic" - even aluminium won't transfer that much heat that fast, by several orders of magnitude.   

       Problem is thermal mass. Houses are (or should be) designed such that they store heat from the sun during the day then release it into the house at night. Over the course of a regular year it averages out to be the most efficient.   

       But there's seasonal variations. So, an active element.   

       Polished, clearcoated aluminium strips, vertically or horizontally on the sun-side exterior of the house. During the summer they're closed during the day and open at night. During the winter, open during the day and closed at night.
FlyingToaster, Jun 10 2015
  

       As others have said, at most 1-2 peltiers at each end (depending on how cold you want it) and a heat pipe in between. That will be a lot more efficient at moving heat.   

       Better yet, if you've got the space, just go with a traditional refrigeration system, which will be even more efficient.
MechE, Jun 11 2015
  

       Peltier Thistle - A bowling ball-sized aluminium sphere, (almost) filled with water, the outside coated with Peltier semiconductor pairs... and a battery as well as plug-in. et cetera.
FlyingToaster, Jun 11 2015
  

       But a heat pipe isn't flexible, which seems to be something [pashute] wants for some reason.
notexactly, Jun 15 2015
  

       Care to bet? (see link)
MechE, Jun 15 2015
  
      
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