The Thermochemical Fallacy of Water-Powered Combustion: An Analysis of Electrolytic Efficiency and the Laws of Thermodynamics

This quantitative analysis evaluates the absolute thermodynamic and electrochemical constraints that prevent an internal combustion engine from operating sustainably on water dissociation products. By utilizing thermochemical state values validated by the National Institute of Standards and Technology, this paper models the complete chemical cycle of an isolated system where water serves as both the primary fuel and the exhaust product. Stoichiometric and enthalpy equations demonstrate that the external electrical work required to dissociate polar covalent bonds in liquid water (Hf=-285.8kJ/mol) establishes a baseline energy threshold that equals the maximum theoretical energy recovered during subsequent hydrogen combustion. When evaluated against the Second Law of Thermodynamics, the system exhibits an unrecoverable energy deficit due to Carnot efficiency limits, activation overpotentials, and ohmic resistance within the electrolytic cell. This investigation calculates the real-world operational net energy yield of a closed-loop water engine, demonstrating that any such apparatus operates as a net energy sink rather than a self-sustaining propulsion generator.