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Home > Archive > Alternative Power sources > September 2005 > Re: Hydrogen is too difficult.
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Re: Hydrogen is too difficult.
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| Landen99 2005-09-02, 7:22 pm |
| So you admit that there is no inherent efficiency bound, but it varies
with Tc and Th (tl,th). Do you admit that the efficiency can approach
100% given sufficiently large Th and small Tc? I infer by your answer
below that you do. If the Carnot engine can easily approach 100% then
why is it so difficult to accept that a fuel cell can do the same? Why
is it so difficult to accept that I measured +90% efficiency on an open
circuit? Why is it so difficult for Don and PV to accept that I am a
physicist? Perhaps it is because Don does't want to hear positive news
about fuel cells, that they are the way of the future and that Don
can't stop the hydrogen economy. Economics is the universal law of
freedom.
BTW, Don is wrong again. "The upper Carnot efficiency limit" is NOT
"one of the most fundamental and most profound core concepts of
thermodynamics" (quotes are from Don). There are only three such core
concepts and they are the three laws of thermodynamics: 1) Energy and
matter are conserved, 2) Entropy always increases, and 3) 0 Kelvin is
impossible. Carnot enters after extensive (elementary) analysis of
heat engines using these core concepts. PV is wrong because he will
not in fact fulfill his pledge to buy a hat and eat it. And no, I will
not prove myself to him, however much I would love to see him eat it.
Andy Landen
Friend of Fuel Cells
PS
I never understood the French.
I wonder if they ever understood their own Statue.
Perhaps they gave it away to America (NY) because they thought we might
have a better chance understanding it.
Don Lancaster wrote:
> Landen99 wrote:
>
>
> That's what those French Veternarians call a "four paw".
>
> The upper Carnot efficiency limit is strictly and positively set by the
> ratio of the absolute input and output temperatures. n = (th-tl)/th =
> delta(t)/th. Or 100x for percent efficiency.
>
> This is one of the most fundamental and most profound core concepts of
> thermodynamics. And should be well known by many junior high school
> science students.
>
> See http://www.tinaja.com/glib/hack64.pdf for thermodynamic fundamentals.
>
> See http://www.tinaja.com/glib/energyfun.pdf for energy fundamentals.
>
> --
> Many thanks,
>
> Don Lancaster
> Synergetics 3860 West First Street Box 809 Thatcher, AZ 85552
> voice: (928)428-4073 email: don@tinaja.com
>
> Please visit my GURU's LAIR web site at http://www.tinaja.com
| |
| Paul Vader 2005-09-13, 2:23 pm |
| Dan Bloomquist <public21@lakeweb.com> writes:
>Landen99 wrote:
>
>
>I missed this one. How do you measure efficiency if no work is done?
For some reason, supernews is eating every one of this guy's posts. I
don't think they do that to google groups overall, so this guy must be some
kook subspecies.
How do you measure ANYTHING on an open circuit?
[color=darkred]
Because you make mistakes that a high-school physics student would get an F
on their papers for making? *
--
* PV something like badgers--something like lizards--and something
like corkscrews.
| |
| Dan Bloomquist 2005-09-13, 2:23 pm |
|
Paul Vader wrote:
> Dan Bloomquist <public21@lakeweb.com> writes:
>
>
> How do you measure ANYTHING on an open circuit?
With a volt meter.
Best, dan.
--
Add one for email
| |
| Paul Vader 2005-09-13, 2:23 pm |
| Dan Bloomquist <public21@lakeweb.com> writes:
>
>With a volt meter.
Then it's not an open circuit anymore. *
--
* PV something like badgers--something like lizards--and something
like corkscrews.
| |
| Dan Bloomquist 2005-09-13, 2:24 pm |
|
Paul Vader wrote:
> Dan Bloomquist <public21@lakeweb.com> writes:
>
>
> Then it's not an open circuit anymore. *
Sure it is.
Best, Dan.
--
Add one for email
| |
| Bill Ward 2005-09-13, 2:24 pm |
| On Wed, 07 Sep 2005 16:30:21 GMT, Dan Bloomquist
<public21@lakeweb.com> wrote:
>
>
>Paul Vader wrote:
>
>Sure it is.
>
Not always, Dan. Typical multimeters usually have about a
10M resistive input Z. There are specialty VMs
(electrostatic) which are effectively open circuit at DC,
but require high voltage. FET input electrometers can have
input R way up there, but probably not quite infinite.
It's all relative.
Regards,
Bill Ward
| |
| Dan Bloomquist 2005-09-13, 2:24 pm |
|
Bill Ward wrote:
> On Wed, 07 Sep 2005 16:30:21 GMT, Dan Bloomquist
> <public21@lakeweb.com> wrote:
>
>
>
> Not always, Dan. Typical multimeters usually have about a
> 10M resistive input Z. There are specialty VMs
> (electrostatic) which are effectively open circuit at DC,
> but require high voltage. FET input electrometers can have
> input R way up there, but probably not quite infinite.
>
> It's all relative.
Sure it is. But in the lab, measuring the voltage of an open circuit is
well understood. Open circuit voltage is a fundamental in Thevenin
equivalent circuits.
Thevenin, google, 408,000 hits.
> Bill Ward
Best, Dan.
--
Add one for email
| |
| Solar Flare 2005-09-13, 2:24 pm |
| In that definition, there is never such a thing as an "open circuit". Air
has conductivity also and therefore no circuit is ever "open"
"Dan Bloomquist" <public21@lakeweb.com> wrote in message
news:skGTe.6487$cg.4363@news02.roc.ny...
>
>
> Bill Ward wrote:
>
>
> Sure it is. But in the lab, measuring the voltage of an open circuit is
> well understood. Open circuit voltage is a fundamental in Thevenin
> equivalent circuits.
>
> Thevenin, google, 408,000 hits.
>
>
> Best, Dan.
>
> --
> Add one for email
>
| |
| Dan Bloomquist 2005-09-13, 2:24 pm |
| What definition?
Solar Flare wrote:
> In that definition, there is never such a thing as an "open circuit"....
| |
| Solar Flare 2005-09-13, 2:24 pm |
| Paul (Darth) Vader's
"Dan Bloomquist" <public21@lakeweb.com> wrote in message
news:MqKTe.533$am.366@news01.roc.ny...
> What definition?
>
> Solar Flare wrote:
>
| |
| Dan Bloomquist 2005-09-13, 2:24 pm |
|
I don't know about Paul's definition. Walk into any lab and ask what the
open circuit voltage is and the guy will grab a voltmeter for your answer.
Best, Dan.
Solar Flare wrote:
> Paul (Darth) Vader's
>
> "Dan Bloomquist" <public21@lakeweb.com> wrote in message
> news:MqKTe.533$am.366@news01.roc.ny...
>
>
>
--
Add one for email
| |
| Don Lancaster 2005-09-13, 2:24 pm |
| Dan Bloomquist wrote:
>
> I don't know about Paul's definition. Walk into any lab and ask what the
> open circuit voltage is and the guy will grab a voltmeter for your answer.
>
> Best, Dan.
>
> Solar Flare wrote:
>
>
Unloaded or very lightly loaded, the point remains that the efficiency
is either zero or utterly negligible under such circumstances.
Efficiency of a solar panel or whatever is optimized at its maximum
power point where the instantaneous iv product is maximized.
Proof at www.tinaja.com/glib/hack65.pdf
Otherwise, it is a trivial circuits 101 exercise.
Efficiencies away from that point are significantly less.
That is why adaptive inverters can wring out a little more in the long
term. Cost effectiveness depends upon complexity versus recovery.
http://www.tinaja.com/glib/energfun.pdf
--
Many thanks,
Don Lancaster
Synergetics 3860 West First Street Box 809 Thatcher, AZ 85552
voice: (928)428-4073 email: don@tinaja.com
Please visit my GURU's LAIR web site at http://www.tinaja.com
| |
| Bill Ward 2005-09-13, 2:24 pm |
| On Wed, 07 Sep 2005 18:29:44 GMT, Dan Bloomquist
<public21@lakeweb.com> wrote:
>
>
>Bill Ward wrote:
>
>
>Sure it is. But in the lab, measuring the voltage of an open circuit is
>well understood. Open circuit voltage is a fundamental in Thevenin
>equivalent circuits.
>
I'm not trying to nit-pick here, Dan, as your statement is
correct most of the time. But some readers will not have
your lab experience and take it literally. Not all lab work
can ignore a microamp at 10V.
Developing instruments such as pH meters, photometers
electrometers, and many other hi-Z DC circuits requires
accurate knowledge of the input Z of the voltmeter (or
electrometer) used to determine the "open circuit" value.
Then the "actual" open circuit voltage can be estimated from
the observed value.
>Thevenin, google, 408,000 hits.
I'm surprised there are only that many hits, as Thevenin
equivalent circuit analysis is fundamental to electronics.
But if the input Z of a meter is significant, it must be
taken into account to estimate an "open circuit" voltage.
Ten megohms is not always insignificant.
Regards,
Bill Ward
| |
| Solar Flare 2005-09-13, 2:24 pm |
| You need to wake up a little buddy. LOL I am not sure you even read what you
posted. (maybe I didn't either?)
I think I was agreeing with you that the "loading" argument is ridiculous.
We are playing semantics with the "open circuit" argument.
"Dan Bloomquist" <public21@lakeweb.com> wrote in message
news:_qLTe.541$am.256@news01.roc.ny...
>
> I don't know about Paul's definition. Walk into any lab and ask what the
> open circuit voltage is and the guy will grab a voltmeter for your answer.
>
> Best, Dan.
>
> Solar Flare wrote:
>
circuit"....[color=darkred]
>
> --
> Add one for email
>
| |
| Paul Vader 2005-09-13, 2:24 pm |
| Dan Bloomquist <public21@lakeweb.com> writes:
>I don't know about Paul's definition. Walk into any lab and ask what the
>open circuit voltage is and the guy will grab a voltmeter for your answer.
My comment was really about efficiency, not voltage, though I admit that I
did say *anything* for dramatic effect. You can't measure efficiency of a
device under a no-load condition, because it by definition isn't doing
any work.
And in most cases (unless you're using expensive lab equipment), when
you're measuring voltage on a supposedly open circuit, you're actually
measuring it under some number of microamps of load. *
--
* PV something like badgers--something like lizards--and something
like corkscrews.
| |
| Dan Bloomquist 2005-09-13, 2:24 pm |
|
Bill Ward wrote:
>
> I'm not trying to nit-pick here, Dan, as your statement is
> correct most of the time. But some readers will not have
> your lab experience and take it literally. Not all lab work
> can ignore a microamp at 10V.
Hi Bill,
Right. That's why the 'well understood'. And at that, measurements do
get done without consideration. Many times I've made a measurement and
thought, 'What's wrong with this picture?', while loading a circuit
enough to skew the result.
For DC it is rearly a concern. A scope probe on an active circuit will
often create a change. But it is usually the capacitive load that gets you.
> But if the input Z of a meter is significant, it must be
> taken into account to estimate an "open circuit" voltage.
> Ten megohms is not always insignificant.
I agree. But in a lab you consider it or use the proper voltmeter.
My bench has a hp3456a. 1000 meg input.
In the case of a fuel cell, 10 megs would not likely be considered a load.
> Bill Ward
Best, Dan.
--
Add one for email
| |
| Dan Bloomquist 2005-09-13, 2:24 pm |
|
Paul Vader wrote:
> Dan Bloomquist <public21@lakeweb.com> writes:
>
>
>
> My comment was really about efficiency, not voltage, though I admit that I
> did say *anything* for dramatic effect. You can't measure efficiency of a
> device under a no-load condition, because it by definition isn't doing
> any work.
Well then, full circle. My original words:
'How do you measure efficiency if no work is done?'
Best, Dan.
--
Add one for email
| |
| Solar Flare 2005-09-13, 2:24 pm |
| When you can divide by zero, let us know and we will tell you.
LOL
"Dan Bloomquist" <public21@lakeweb.com> wrote in message
news:vh0Ue.621$am.420@news01.roc.ny...
>
>
> Paul Vader wrote:
>
answer.[color=darkred]
I[color=darkred]
a[color=darkred]
>
> Well then, full circle. My original words:
>
> 'How do you measure efficiency if no work is done?'
>
> Best, Dan.
>
> --
> Add one for email
>
| |
| Dan Bloomquist 2005-09-13, 2:24 pm |
|
Solar Flare wrote:
> When you can divide by zero, let us know and we will tell you.
Why would I want to divid by zero?
Best, Dan.
--
Add one for email
| |
| Solar Flare 2005-09-13, 2:24 pm |
| Why are you asking me that?
"Dan Bloomquist" <public21@lakeweb.com> wrote in message
news:rn3Ue.634$am.418@news01.roc.ny...
>
>
> Solar Flare wrote:
>
>
> Why would I want to divid by zero?
>
> Best, Dan.
>
> --
> Add one for email
>
| |
| daestrom 2005-09-13, 2:25 pm |
|
"Solar Flare" <sflare@hotmail.com> wrote in message
news:9PmdnfdtYOquXb3eRVn-sA@golden.net...
> When you can divide by zero, let us know and we will tell you.
>
> LOL
If no work is done, but energy is put into the system, you don't divide by
zero. The work done goes in the numerator, not the denominator. The energy
you put into the system goes in the denominator.
The only time you would have a /0 problem is if you put zero energy into the
system. (like so many 'free energy' kooks claim they can do).
daestrom
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