Help! Need to get about 3 watts from HEAT.

[Raymond]

Hey, smart people out there.

How can I generate, about 6 volts at 1.5 amps, using only heat.
The heat will be about 200 degrees F, sometimes hotter.

I can't find any thermocouples that generate much more than 20 mills.
And, I'm not stuck on thermocouple technology.

Help.

If you can help me, I'd love to reciprocate ($). Feel free to e-mail
me at
[email protected]

 

[Frank Bemelman]

Hey, smart people out there.

How can I generate, about 6 volts at 1.5 amps, using only heat.
The heat will be about 200 degrees F, sometimes hotter.

I can't find any thermocouples that generate much more than 20 mills.
And, I'm not stuck on thermocouple technology.

Help.

If you can help me, I'd love to reciprocate ($). Feel free to e-mail
me at
[email protected]

3 watts or 9 watts? What are you going to do with that 6V? In the
end, it will get converted to heat anyway

 

[Ralph & Diane Barone]

Hey, smart people out there.

How can I generate, about 6 volts at 1.5 amps, using only heat.
The heat will be about 200 degrees F, sometimes hotter.

I can't find any thermocouples that generate much more than 20 mills.
And, I'm not stuck on thermocouple technology.

Help.

If you can help me, I'd love to reciprocate ($). Feel free to e-mail
me at
[email protected]

If you had another 20 degrees or so, you could run a steam powered
generator

 

[Fred Bloggs]

Hey, smart people out there.

How can I generate, about 6 volts at 1.5 amps, using only heat.
The heat will be about 200 degrees F, sometimes hotter.

I can't find any thermocouples that generate much more than 20 mills.
And, I'm not stuck on thermocouple technology.

Help.

If you can help me, I'd love to reciprocate ($). Feel free to e-mail
me at
rrgoldstein@yahoo.

You want something like this:
http://www.sitechina.com/thermoelectric/Pspec.html

 

[Paul Burke]

Hey, smart people out there.

How can I generate, about 6 volts at 1.5 amps, using only heat.
The heat will be about 200 degrees F, sometimes hotter.

I can't find any thermocouples that generate much more than 20 mills.
And, I'm not stuck on thermocouple technology.

We bought a share in a canal boat last year (if you've not tried the
English canals, do so if you can, it's a Zen-like experience), and part
of the equipment was a "magic" fan that sits on top of the Diesel stove,
and wafts the air along the long narrow cabin when the stove heats up. A
simple thermopile application, but a source of great perplexity to our
non- technical partners.

Paul Burke

 

[Ian Stirling]

If you had another 20 degrees or so, you could run a steam powered
generator

You can run steam engines at below atmospheric pressure.
Sealing gets interesting.

 

[Eduardo]

Hey, smart people out there.

How can I generate, about 6 volts at 1.5 amps, using only heat.
The heat will be about 200 degrees F, sometimes hotter.

I can't find any thermocouples that generate much more than 20 mills.
And, I'm not stuck on thermocouple technology.

Help.

If you can help me, I'd love to reciprocate ($). Feel free to e-mail
me at
[email protected]

Perhaps, something like that:
http://www.productsforanywhere.com/market/mkt_pages/radio_lantern/radio_lant
ern.html

Regards.
Eduardo.

 

[Pat Ford]

Perhaps, something like that:
http://www.productsforanywhere.com/market/mkt_pages/radio_lantern/radio_lant
ern.html

Regards.
Eduardo.

or a peltier junction cooler??

 

[Ralph & Diane Barone]

You can run steam engines at below atmospheric pressure.
Sealing gets interesting.

Trust a guy named Stirling to find my errors in thermodynamics...

 

[James Meyer]

Hey, smart people out there.

How can I generate, about 6 volts at 1.5 amps, using only heat.
The heat will be about 200 degrees F, sometimes hotter.

I can't find any thermocouples that generate much more than 20 mills.
And, I'm not stuck on thermocouple technology.

Help.

If you can help me, I'd love to reciprocate ($). Feel free to e-mail
me at
[email protected]

You are confusing the physics terms associated with the problem.

Heat is something fundamentally different than temperature.

A match flame may reach a temperature of 1000 degrees, but the heat
contained in that flame would not be enough to make a decent cup of tea much
less warm a whole house or move your car along the road.

You are wanting to convert energy from one form to another. In order to
get energy out of a conversion process, you have to put more energy in than you
expect to get out. Temperature by its self does *not* equate to energy. There
is vastly more energy stored in a ton of water at 200 degrees than there is in a
match flame at 1000 degrees.

Where is the 200 degree "heat" that you are trying to convert?

Jim

 

[Artist]

You will need a working fluid that vaporizes well below 200F. The
coolant used in air conditioners maybe. Then, once vaporized in boiler
and under pressure, it must be passed through either a turbine or a
cylinder with a piston. These are coupled to a generator to convert the
energy from the heat that can do useful work (enthalpy) into
electricity. You will need a low temperature heat sink to remove the
heat energy in the fluid that cannot do useful work (entropy) from the
fluid in gas phase to return it to liquid phase. Then this liquid must
be pumped back into the boiler.

There is not a way to get significant amounts of electriciy from heat
without moving parts.

I recommend mechanical engineering text books on thermodynamics.

Hey, smart people out there.

How can I generate, about 6 volts at 1.5 amps, using only heat.
The heat will be about 200 degrees F, sometimes hotter.

I can't find any thermocouples that generate much more than 20 mills.
And, I'm not stuck on thermocouple technology.

Help.

If you can help me, I'd love to reciprocate ($). Feel free to e-mail
me at
[email protected]

--
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[Robert Baer]

You will need a working fluid that vaporizes well below 200F. The
coolant used in air conditioners maybe. Then, once vaporized in boiler
and under pressure, it must be passed through either a turbine or a
cylinder with a piston. These are coupled to a generator to convert the
energy from the heat that can do useful work (enthalpy) into
electricity. You will need a low temperature heat sink to remove the
heat energy in the fluid that cannot do useful work (entropy) from the
fluid in gas phase to return it to liquid phase. Then this liquid must
be pumped back into the boiler.

There is not a way to get significant amounts of electriciy from heat
without moving parts.

I recommend mechanical engineering text books on thermodynamics.


--
If sj. appears in my email address remove it to respond.
It is a spam jammer.

Fight the mark of the beast: http://www.house.gov/paul/privacy
Stop judicial corruption: http://www.Jail4Judges.org
Support antispam legislation: http://www.cauce.org

Hulk Hogan for President!

Me thinks that a thermocouple has no moving parts...

 

[Tim Shoppa]

Me thinks that a thermocouple has no moving parts...

And it'll never be as efficient as a an engine with moving parts.

Not knowing the application it's hard to say if efficiency or "no
moving parts" is a requirement.

RTG's use thermocouples and have a "sweet spot" of a few hundred
watts. But the price/performance point for a deep space probe may
be different than the intended application here . (Not that all
RTG's go into deep space probes, either...)

Tim.

 

[Bill Schuh]

You can multiply the thermocouple circuit output by putting a bunch of
alternating ones in series-kind of like an extended "WWWWWW...." with
one set of apex being at the higher temp and the other set of apex
being at the lower temp. The "legs" of the "W" are alternating
positive and negative polarity thermoelements of the thermocouple.
That's how thermoelectric generators work but on a microscale. If you
want to see a macroscale example then tear apart the bulb of an old
thermocouple from your water heater.

So if you have a TC that generates 20 mV then all you need is 1000
pairs in series to generate 20V : ) . Seems like a thermoelectric
module would be a better solution. I believe you can gang them up to
get higher outputs.

Bill

 

[Fred Bloggs]

You can multiply the thermocouple circuit output by putting a bunch of
alternating ones in series-kind of like an extended "WWWWWW...." with
one set of apex being at the higher temp and the other set of apex
being at the lower temp. The "legs" of the "W" are alternating
positive and negative polarity thermoelements of the thermocouple.
That's how thermoelectric generators work but on a microscale. If you
want to see a macroscale example then tear apart the bulb of an old
thermocouple from your water heater.

So if you have a TC that generates 20 mV then all you need is 1000
pairs in series to generate 20V : ) . Seems like a thermoelectric
module would be a better solution. I believe you can gang them up to
get higher outputs.

Bill

This thread is several years old and links to suitable heat recovery
conversion products were given at that time. This "artist" is a
newsgroup troll.