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Re: Peltiers, Ins and Outs

Robert H corrected me re descendance from midwest Hs:

> No, no midwest heritage! Grew up in Boston, came to California when I
> was
> 21, moved to Oregon 20 years later...

I meant I had come from the midwest Hs.  There's either never enough or
too many commas when you need them.

Then Robert H said:
> There used to be someone on this list named Scott Hudson which I
> would
> always get confused with YOU, Scott Hieber.. and both of you
> contributed to
> the defense fund...

Oh great, now you're naming names about the defense fund. Probably get
my midwest dragged into court.  ;-)  

I had said:
>>Thermoelectric solid state devices have been around for a
> while and generally their price per BTU/hr capacity is very high
> compared to conventional "Freon" chillers that compress and expand
> chlorflorocarbon gases to move heat around.<<

So Robert H said:
> Thats the kind of missing info I was wondering about...AZOO doesnt
> give much
> in the way of technical specs...no big surprise there for an Asian
> company...so I wondered about BTUs, voltage and so forth... is it
> common for
> most chillers to be heaters as well? I thought that was sort of
> unique, but
> I'm getting the impression thats commonplace?

The devices, the little solid state chips themselves (the peltiers) are
very small and inexpensive.  To get a decent amount of heat movement
(for something bigger than a computer CPU chip) you need an array of
the chips mounted onto a "heat" sink and a fan to move air over the
heat sink.  Since a peltier works by moving it's own heat to one side
of itself, the other side becomes colder and can absorb more heat -- as
long as you keep drawing off the heat when it moves to the "hot" side. 
The peltier is neither a neater nor a cooler until you put it into an
application.  Apply the "hot" side and you have a heater, apply the
other, well you get the idea.  These ought to become cheaper than
gas-type chillers, eventually.  But last I looked, to get the same
amount of cooling, you paid as much as three to ten times more money
per btu/hr for, say, a 5,000 btu/hr or larger device than for a similar
sized conventional chiller.  IF someone wants to do a little research
on options for chilling and relative up front costs per btu/hour and
operating costs per btu/hr/year.  That would be interesting stuff for
folks with lots of lights.

BTW, if you take a conventional ("freon" type) air conditioner and put
the cooling (a.k.a. evaporator) side outside the house and the heating
(a.k.a. condensor) side inside the house, then you essentially have
what's called a heat pump.  Air conditioners move air from one side of
the unit to the other but they pump cloroflorocarbon gas to it. 
Cloroflorocarbons are used because, to oversimplify, they violate
Boyles Law very well -- But how they do so is what makes the stuff so
bad for the ozone layer.  So peltiers are a nice way to go for a lot of
reasons -- I think the relatively new peltier technology is relatively
expensive except for cooling very small hot items like Intel computer
chips running at 2 GHz.

Regards all,
Scott H., fundwise a small monthly contributer that has been outted.

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