Expanding Life Cycle Assessment boundaries through Thermodynamic Entropy: A comparative study of combustion and electric cars

The global transition from internal combustion engine vehicles (ICEVs) to battery electric vehicles (BEVs) as a strategy to mitigate climate change requires objective, physics-based metrics to quantify energy and environmental impacts. Traditionally, carbon dioxide (CO ₂ ​) emissions have been the primary metric, often modelled through Life Cycle Assessment (LCA). This study proposes a novel framework based on entropy analysis to provide a unified thermodynamic evaluation of the processes involved in vehicle operation. A comparative analysis is conducted on three Volkswagen Golf variants: gasoline, diesel, and electric. The entropies associated with fuel combustion, electricity generation, CO ₂ ​ emissions, atmospheric emissivity changes, and noise pollution are quantified using fundamental thermodynamic models. For the BEV, the entropy related to battery manufacturing and recycling is integrated using GREET© and EVERBATT© frameworks. Our results show that for a functional unit of 100 km, the gasoline vehicle generates an entropy of 599 kJ K⁻¹, the diesel 492 kJ K⁻¹, and the electric vehicle 352 kJ K⁻¹. Entropy emerges as a universal, multi-dimensional metric capable of reproducing established CO ₂ ​ trends while incorporating previously fragmented impacts, such as atmosphere emissivity an acoustic pollution. Crucially, this entropic approach remains valid beyond the current decarbonization paradigm, providing a permanent tool for evaluating any energy transformation process.