On 11-12-26 03:26 PM, Mary Yugo wrote:
On Mon, Dec 26, 2011 at 12:22 PM, Stephen A. Lawrence <[email protected]
<mailto:[email protected]>> wrote:
On 11-12-26 02:57 PM, Mary Yugo wrote:
Try responding to a real argument: if the claim, as Aussie
Guy made it, is for a device with a COP of 5 over an input
measured in watts, then why not close the loop? What COP
would you need? 10? 100? what? Defkalion, by the way,
claims 35x.
As I said elsewhere, it depends on the temperature rise in the
cell caused by the PF effect. Depending on how hot the cell
operates, a reasonable estimate might be a COP of 30 to make it
theoretically possible to close the loop. That's based on a guess
that the PF effect warms the cell by 10 degrees C.
In practice the requirement to close the loop with a wet CF cell
is likely to be more stringent than that.
I understand but, not to drive this into the ground, why is it
necessarily so? Is there nothing you can do to such a cell to get a
higher delta T? Larger electrodes? More current? Less coolant
flow? Obviously I don't know -- just throwing out some guesses.
That's really a different question.
The question you first posed was a request to know whether or why not AG
was or wasn't going to close the loop with his COP=5 cells, and that's
all I was addressing: With COP=5 and a reasonably typical wet CF cell,
it's theoretically impossible to close the loop. Hacking the
"borrowed" cells to boost the efficiency is outside the scope of that
particular question.
Now, to take up your second question, should it be possible to build a
wet CF cell which gives enough thermal boost due to the PF effect so
that you can get something useful out of it? Jed and Ed Storms have,
IIRC, both alleged that it should be possible. You seal the cell and
pressurize it, so it can run toasty warm, and you do something nobody's
figured out yet with the electrodes to get the reaction rate up really
high, and the result is something which makes enough heat to be good for
something. Frankly, it seems to me that starting with an electrolysis
cell is starting with one foot in a bucket of cement if you want useful
energy out, but I haven't run any numbers so the True Believers (as
opposed to the so-so believers) will no doubt jump on me for being
needlessly negative.
(Somewhere along the line this starts looking like the SSPS argument,
which I think I first heard back when I was in college: You can run an
SSPS at a low enough downlink energy level so that the energy density is
less than that of sunlight, and still get lots of power out of a
reasonable size antenna farm, so the idea is obviously totally
practical. BZZZT! says my intuition, That can't be right! If the
energy density is that low, no way you're going to get anything useful
out of a practical antenna farm ... and if you can why not replace the
rectennas with solar panels and dispense with the satellites ... but all
I've ever gotten for that observation is grief from the True Believers.)
