Calorimetry in cold fusion experiments

Calorimetry is an essential part of cold fusion experiments. Cold fusion researchers use different types of calorimeters, such as isoperibolic, flow, and Seebeck. The accuracy of the calorimetry has been critiqued by Lewis, Wilson, Shkedi, Jones, and Shanahan. Cold fusion researchers find these critiques unconvincing and not applicable to other experimental designs.
The majority of a review panel organized by the US Department of Energy (DOE) in 1989 found that the evidence for the discovery of a new nuclear process was not persuasive. In 2004, the DOE convened a second cold fusion review panel which reached conclusions that were similar to those of the 1989 panel.
Critique
Shkedi and Jones
In some electrolysis cells running at low voltage, internal recombination of hydrogen and oxygen can create the appearance of excess heat. This is called the "Faraday-efficiency effect".
In 1991-1993, a group of investigators led by Zvi Shkedi built well-insulated light-water electrolysis cells and calorimeters which included the capability to measure the actual Faraday efficiency in real time. The average Faraday efficiency measured in these experiments was 78%. With this taken into account, the calculated excess heat was 0.13% +/- 0.48% of input power. If instead a Faraday efficiency of 100% was assumed, the apparent excess heat was 21%. The investigators concluded "All reports claiming the observation of excess heat should be accompanied by simultaneous measurements of the actual Faraday efficiency."
Fritz Will, former president of the Electrochemical Society, noted in his review of Jones' paper that " fraction of O2 recombining with H2 decreases significantly with increasing current density. On the basis of their results at low current densities, a group of researchers recently concluded that H2 + O2 recombination is the source for the "excess heat' reported by other groups and attributed by some to 'cold fusion'. However, reported excess heat values, ranging from a low of 23% at 14 mA/cm to a high of 3700% at 6 mA/cm , are much larger than can be explained by recombination. Whatever the explanation for the large amounts of excess heat reported by various groups, H2 + O2 recombination must be rejected as a tenable explanation." However, the efficiencies "were determined by measuring the combined rates of gas evolution" regarding the Szpak, et. al measurement), so it is unclear whether the measured efficiencies apply to any particular cold fusion event.
Shanahan

In 2002, Shanahan speculated the apparent excess heat signals were arising from a systematic error he called the calibration constant shift (CCS). Shanahan reanalyzed calorimetric data provided by E. Storms under the assumption that no excess power was in fact present, and found that a minor (1-3%) change in the calorimeter calibration constants was all that was required to explain the apparent excess power. Shanahan also proposed that the cause of the shift was a redistribution of heat in the apparatus, which is similar to one of the earlier complaints against Fleischmann-Pons type of calorimetry (single point temperature measurement being suceptible to hot spots). Shanahan further speculated that such a redistribution might arise from unexpected hydrogen-oxygen recombination at the electrode.
In July 2003, Szpak, in a paper co-authored with Fleischmann, said that such recombination reaction is not supported by experimental results. Three years later, Storms said that even when a large change in where a large amount of heat is generated within the cell is made on purpose in a flow calorimeter, little or no effect on the calibration constant is observed. Shanahan responded to Storms in a back-to-back publication that Storms' own data displayed just such effects and that such effects were capable of explaining Storms' excess heat signals. His response included a breakdown of the 10 experimental runs into 4 sequential sets based on what seemed to be a clear time-dependent shift or reset in the calibration constants. This time dependence suggests a chemical aging effect that was reversed by in-cell processing, further emphasizing the non-nuclear nature proposed by Shanahan. He concluded that the chemical explanation he presented deserves an honest experimental test.
In his book, Storms said that the 1.2% variation of the calibration constants he measured proves that the calibration errors proposed by Shanahan are absent. He also said that Seebeck and flow calorimeters are immune to these potential errors, although the isoperibolic method can be affected. However Storms' book did not analyze Shanahan's final latest publication, which refuted these same points.
Shanahan insists that the conventional explanation for apparent excess heat -- heat from the recombination of dissolved or suspended electrolysis products -- must be tested along with the unconventional nuclear 'cold fusion' explanation.

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