Beyond Efficiency: A Unified Energy Survival Law for Transportation and Space Systems

Classical energy efficiency metrics systematically overestimate real-world performance because theymodel energy conversion as a single-stage process and implicitly neglect irreversible thermodynamicdegradation. Across biological metabolism, electric transportation, information systems, and spaceflight,observed system-level outputs consistently fall far below what component-level efficiencies wouldpredict. These discrepancies are most evident in advanced electric vehicles and reusable launch systems,where increases in battery capacity, power, or thrust do not yield proportional gains in driving range orpayload mass.This paper introduces a Unified Energy Survival–Conversion Law that reformulates useful output as asurvival-limited, multi-stage process governed by irreversible thermodynamics and finite conversioncapacity. An energy survival factor (Ψ) is defined to quantify the fraction of absorbed energy thatpersists against transport losses and entropy generation. When coupled with an internal conversioncompetency term (C_int), the framework yields a universal performance relation:𝐸useful = 𝐸in ⋅ Ψ ⋅ 𝐶intThe law is validated against empirical data from biological ecosystems, electric vehicles, and reusablelaunch systems. Case studies involving Tesla and SpaceX demonstrate that performance saturationarises from survival degradation and bounded conversion capacity rather than inefficient motors orengines. The framework is thermodynamically consistent, experimentally falsifiable, and independent ofenergy source or system scale, offering a unified physical basis for diagnosing performance limits andguiding system-level optimization. Please check the attachment for details