| Feature | PTC 4.1 (1964) | PTC 4-2013 (Steam Generating Units) | |--------|----------------|--------------------------------------| | | Minimal | Yes, uncertainty analysis, data quality | | Loss categories | 7 standard losses | Refined, includes air heater leakage method | | Uncertainty quantification | Not explicitly | Full Type A/B uncertainty | | Fuels | Fossil + basic biomass | Expands to catalytic, plasma, etc. | | Clarity | Difficult (units: kCal, Btu, mixed) | Improved SI/US customary tables |
ASME PTC 4 vs PTC 4.1: Efficiency Study | PDF | Uncertainty - Scribd Asme Ptc 4.1.pdf BEST