Subject: Re: Thermocouples

From: [email-masked] (DaveHatunen)
Date: Fri, 17 Feb 1995 15:29:11 GMT

In article <[email-masked]>,
PFEIFFER  <[email-masked]> wrote:
>Dave Hatunen says:
>> Again: thermocouples require two junctions, and the emf is a function
>> of the temperature differential between them. So if you already have a
>> source of higher temperature, then, with the other junction at ambient,
>> you can produce a small amount of energy. But if you do not have a
>> temperature differential, then thermocouples are useless.
>>
>In many cases you have already temperature differentials.
>This is the nice thing with thermocouples
>Sources of surplus high temperatures you have for example in  the case of
>power stations or even by some solar applications let alone some
>industries as the steel industry. The question is the efficiency and especially
>the costs per kWh.

Quite true. But I believe the original poster was under the impression
that somehow they generated an emf from only the one temperature.

Once you have a temperature differential there are all sorts of ways to
derive a little power; thermocouples are probably the worst choice
except under very singular circumstances.

-- 

    ********** DAVE HATUNEN ([email-masked]) **********
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