System-Level Survival Optimization for Efficiency and Output Recovery in Thermal Power Plants

Thermal power plants operating under modern grid conditions increasingly experience measurable efficiency degradation during part-load, load-following, and cyclic operation. Conventional optimization strategies primarily rely on fuel input scaling or isolated component adjustments, often neglecting system-level interactions among transport losses and irreversibilities. This study presents a unified survival-based exergy framework for structured output recovery that remains fully consistent with the First Law, Second Law, and Carnot efficiency constraints. Electrical output is formulated as: Pelec=Ein Ψ Cint where Ein represents fuel chemical energy input, Cint denotes turbine–generator internal conversion competency, and Ψ is a system-level survival factor defined as: Ψ=AE/TE+ε Here, AE is the useful exergy that survives to the work-producing stage, TE represents transport and auxiliary losses, and ε=T0Sgen quantifies irreversibility according to the Gouy–Stodola theorem. Under this formulation, part-load efficiency degradation is shown to arise from increased entropy generation and transport losses rather than insufficient fuel input. The survival factor is further decomposed multiplicatively across subsystem blocks—including combustion, boiler heat transfer, steam throttling, turbine expansion, condenser performance, and auxiliary consumption—allowing collapse-point identification through sensitivity analysis: ∂Ψ/∂ki=Ψ/ki This enables quantitative ranking of high-leverage recovery targets. Numerical evaluation demonstrates that coordinated improvements of 2–3% in turbine efficiency, 1–2% in condenser performance, and 1–2% in auxiliary load reduction can collectively produce 5–8% net electrical output increase at constant fuel input. Such gains correspond directly to reductions in entropy generation and transport loss while remaining strictly below the Carnot limit. The proposed framework does not introduce new thermodynamic principles; rather, it reorganizes classical exergy theory into an operational optimization structure suitable for real-world thermal power plant performance recovery. By reframing output enhancement as a survival maximization problem instead of a fuel maximization strategy, the methodology provides a thermodynamically grounded pathway for efficiency stabilization and output recovery under flexible grid conditions. Please check the attachment for details