Measuring heat in plasma electrolysis

In a 2000 paper, Tadahiko Mizuno and colleagues reported excess heat during high-voltage electrolysis with a tungsten cathode. Their apparatus combined open-cell and flow calorimetry, with an electrical heater used to calibrate heat recovery.

Jean-Louis Naudin published a related experiment in May 2003. In a 45.2-second run, the electrolyte warmed from 70 to 96 °C and the cell lost six grams of mass. He calculated an output/input energy ratio of 1.10 from the temperature rise and an evaporation term. The calculation assumes that all lost mass was vaporized water. The report lists instrument accuracies but gives no propagated uncertainty for the final ratio.

Biberian and colleagues’ 2015 pressurized-cell study also reported a preliminary heat surplus. They identified two measurement problems: the unstable discharge complicates electrical power measurement, and expelled droplets can be counted as vapor.

Vapor or droplets?

The distinction changes the calculated output. An evaporation term assigns latent heat to the lost water; liquid droplets have not undergone that phase change. Testing the reported surplus requires measuring these losses separately, alongside calibrated calorimetry and synchronized voltage–current integration. Repeated runs and matched controls would then show whether the surplus persists within the measurement uncertainty.