A calorimetric study of the electrolysis of D2O and H2O at palladium cathodes

A search for excess heat production during the electrolysis of D₂O or H₂O at palladium cathodes was conducted using a sensitive flow calorimeter. A total of 20 long-term experiments using 10 control cells and 10 test cells was performed and the effects of different electrode pretreatments and electrolysis conditions were examined. In all cases, the thermal output from the cell matched the Joule input energy within the experimental error of ± 1.5%. These results provided no evidence for any excess heat production over the aggregated cell operating time of 17762 h.