Physical Transformation AtlasPTA
System · system-pathway:natural-gas-combined-cycle · commercial

Natural-gas combined-cycle plant

Combustion gas-turbine plant (topping-cycle)Steam Rankine plant (bottoming-cycle)

A topping gas turbine delivers electrical work and hands its exhaust enthalpy through heat-recovery steam generators to a bottoming steam Rankine cycle that delivers more; the two generators' outputs add. The combined cycle's efficiency belongs here and to neither member — 46.93 % at the Omani plant Al Mhanna et al. 2024 model — while each member keeps its own linear route and checks.

what a system is
Two or more linear pathways, each keeping its own route and checks, joined by a documented residual stream. The eight physics checks are not run over the system; it is not clear merely because its members are — every handoff must also be demonstrated.
handoffs
1 recorded · weakest status demonstrated
members' core checks
Combustion gas-turbine plant: 1 core check unresolved · Steam Rankine plant: 1 core check unresolved — unresolved describes the atlas's evidence coverage of a member route, never a doubt about a plant that runs.
knowledge level
K8 · commercial technology

Members and their routes' checks

  1. 1
    Combustion gas-turbine planttopping-cyclecommercial
    TYPED ✓ENERGY ✓AVAILABILITY ✓THERMO BOUND ?DIMENSIONAL —BOUNDARY ✓REGIME ✓COVERAGE ✓· 1 core unresolved
  2. 2
    Steam Rankine plantbottoming-cyclecommercial
    TYPED ✓ENERGY ✓AVAILABILITY ✓THERMO BOUND ?DIMENSIONAL —BOUNDARY ✓REGIME ✓COVERAGE ✓· 1 core unresolved

Handoffs between members

  1. 1
    Combustion gas-turbine plant → Steam Rankine plantrecovered heatdemonstrated
    thermal energy leaves the first member as Hot gas and establishes Temperature gradient, the disequilibrium the second member's route starts from.
    • gas-turbine exhaust transfers residual enthalpy through a heat-recovery steam generator to establish the bottoming steam-cycle hot-side temperature relative to its condenser
    Al Mhanna 2024's local plant: 540.7 °C gas-turbine exhaust into two-pressure heat-recovery steam generators (HP 235,400 kg/h and LP 40,000 kg/h feed; HP superheater exhaust 471.48 °C), the steam turbine delivering 61.5 MW
    refs [1]

Outputs

topping-cycle
Electrical work · adds into the system output
bottoming-cycle
Electrical work · adds into the system output

Measured or reported performance of the system

  1. combined-cycle thermal efficiency46.93%plant2024
    basis: net gas-turbine plus steam-turbine power divided by natural-gas LHV input
    local plant baseline (a 678 MW combined-cycle station in Oman, one gas-turbine train); natural gas 9.2 kg/s at LHV 43,662 kJ/kg; gas turbine ≈ 127 MW, steam turbine ≈ 61.5 MW; gas-turbine inlet 1050 °C, exhaust 540.7 °C — the plant's own figure (Table 3, local plant data); (127 + 61.5) MW over 9.2 kg/s × 43,662 kJ/kg = 401.7 MW reproduces it exactly — a verification, not a second measurement; the paper's Aspen Plus simulation gives 46.28 %
    refs [1]

Sources

  1. [1]
    N. M. Al Mhanna, I. Al Hadidi, S. Al Maskari. Simulation and Energy Analysis of Integrated Solar Combined Cycle Systems (ISCCS) Using Aspen Plus (2024)
    Energies 17, 3986 · doi:10.3390/en17163986 · record
  2. [2]
    A. Bejan. Advanced Engineering Thermodynamics (4th ed.) (2016)
    Wiley · doi:10.1002/9781119245964 · crossref ✓ 2026-09-19 · record

Cite this system

Physical Transformation Atlas (2026). system system-pathway:natural-gas-combined-cycle: Natural-gas combined-cycle plant. Dataset revision rbfbfcbb70e57 (hash of the canonical data). https://physical-transformation-atlas.wldud5192.workers.dev/system/natural-gas-combined-cycle

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