Dr. Shanahan has now published two papers (Thermochimica Acta 428 (2005)
207, Thermochim. Acta 382 (2002) 95) in which he argues that excess heat
claimed to be produced by cold fusion is actually caused by errors in
heat measurement. In particular, he proposes that unrecognized changes
in the calibration constant are produced by changes in where heat is
being generated within the electrolytic cell over the duration of the
measurement. Because these papers may lend support to those people who
reject the cold fusion claims, these erroneous arguments used by
Shanahan need to be answered.
Shanahan makes two basic assumptions: that heat can be produced at
different locations within a cell because recombination between the
evolved D2 and O2 gases can take place at different locations, and that
a flow calorimeter is sensitive to where heat is being produced in the
cell. Both of these assumptions have been shown by experimental
observation to be false.
As anyone who has actually viewed an electrolytic cell will testify, all
D2 is generated at the cathode and all O2 is generated at the anode,
with both gases rising rapidly to the surface as bubbles. Bubbles
contain mainly only one of these gases. Consequently, recombination can
not take place within a bubble, as Shanahan proposes. In addition, it
is well known that H2 (D2) and O2 gases can not react in the absence of
a catalytic solid surface or without an energy source. Very few bubbles
reach the opposite electrode so that surface recombination on the
electrode surface is also small. The recombination process has been
explored by a number of people and is summarized by Storms
(www.LENR-CANR.org/StormsEacriticale.pdf ).
Before discussing the location of heat production and the sensitivity of
the calibration constant, I would first like to provide a general
background about calorimetry. More details can be found in “Calorimetry
101 for Cold Fusion” found at www.LENR-CANR.org. Three types of
calorimeters are normally used to measure heat production in cold fusion
cells. The isoperibolic type measures temperature drop across a thermal
barrier located between the electrolyte and a constant temperature bath.
If the cell wall is used as the barrier, errors can result if the source
of heat changes location. Such errors are well known and were
acknowledged in earlier studies. Most work is now based on use of a
flow calorimeter, which determines heat production based on the
temperature change of water flowing through or around the cell. This
design has been examined previously to determine the effect of heat
location, as discussed by Storms
(www.LENR-CANR.org/StormsEdescriptio.pdf). For example, calibration
using an internal resistor causes heat to be produced at an entirely
different location compared to when energy is applied by electrolysis.
Nevertheless, electric power applied to a resistor gives the same
calibration constant as when energy is applied to a dead cathode. In
other words, a large change in where heat is generated within the cell
has little or no effect on the error in measured heat. More recently,
Seebeck calorimeters are used, which generate a voltage proportional to
the temperature difference across a thermal barrier that completely
surrounds the cell. This type is also completely immune to where heat
is being generated within the cell, yet excess heat has been reported.
In addition, recombination is frequently not an issue because most
people now use a recombiner within the cell so that all D2 and O2 is
returned to D2O within the calorimeter. A person does not need to
speculate, as Shanahan has done, about the effect caused by moving the
source of heat because no such effect has been observed when using a
flow or Seebeck calorimeter.
Shanahan also comments about an earlier paper of mine
(www.LENR-CANR.org/Stormsexcesspowe.pdf) about which he published an
earlier critique (Thermochim. Acta 382 (2002) 95). In his most recent
paper, he rejects my claim for excess energy because an error in the
calibration constant of 2.5% would explain the claimed excess. He does
not acknowledge that I found only a 1.6% variation based on many
measurements done over three months. In addition, he has not explained
why the calibration constant would suddenly make such a change exactly
when applied current was changed to initiated the excess power and do
this four times, and then fail to change at other times. Of course, it
is easy to reject any claim just by assuming a large enough experimental
error, but is this a proper analysis?
Anyone who has actually used such calorimeters knows that errors can
occur, which might be interpreted as excess heat. Unfortunately, the
analysis made by Shanahan is so poorly done that these errors remain
unexplored. In addition, it is hard not to feel embarrassed for the
peer review process that was applied to these papers and the reputation
of the journal in which such papers are published. Papers that attempt
to show that cold fusion is not real should be evaluated using the same
standards skeptics want applied to papers that support such claims.
- Papers by Shanahan Edmund Storms
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