Energy mass balanceCostingCarbon footprintGas & steam turbines
Combined-cycle gas turbine (CCGT) power plant
Natural gas combined cycle for baseload or mid-merit: net output, HHV efficiency and heat rate, gas use, CO2, all-in CAPEX, fixed and variable O&M and LCOE in EUR/MWh on the Fraunhofer ISE 2024 basis, gas in MWh HHV like the OCGT calculator.
- CurrencyEUR 2024
- Battery limitfully financed
- 51 documented assumptions
- Updated27 Oct 2026
Mass and energy balance
What the asset draws and delivers for the case and load you choose.
Reference case
Equivalent hours per year at net capacity (capacity factor = hours / 8,760). Default 6,300 h is the ISE 2024 high (baseload) case for a CCGT; 3,000 h is the ISE low (mid-merit) case. Below 3,000 h a plant is a peaker and an OCGT is usually cheaper.
Flows
- In: Natural gas (HHV)—
Asset
Combined-cycle gas turbine power plant
- Out: Electricity (net)—
Annual quantities at the current usage. Band width: share of energy in; non-energy flows are not to scale.
Net electrical output at the high-voltage terminals, after auxiliaries. Default 627 MW is the EIA AEO2025 1x1x1 single-shaft H-class reference (case 6); the 2x2x1 H-class case is 1,227 MW. The range starts at 418 MW, the smallest H-class combined cycle EIA costs (AEO2020, 1x1x1 single shaft): below it no H-class combined cycle exists, plants use F-class, industrial or aeroderivative gas turbines with a lower efficiency than the H-class heat rate used here, so they are out of scope. The model CAPEX per kW follows a 0.91 scale exponent fitted on the two AEO2025 cases (USD 921/kW at 627 MW, USD 868/kW at 1,227 MW), so it falls by about 6 % when the plant doubles; the fixed O&M per kW follows a 0.63 exponent from the same two cases. Above 1,227 MW the laws are an extrapolation.
- Fuel input at full load (HHV)
- — MW
- Annual net generation
- — MWh/year
- CO2 emission rate at full load
- — t/h
CAPEX
Specific cost at this size, what backs it, and how it behaves with scale.
Specific CAPEX at this size
—
Reference size 627 MW
Derived from EIA AEO2025 Table 1-2 (two sizes), cross-checked on AEO2020
Model value: the reference case CAPEX scaled to the plant size. Customized: your own all-in figure (a vendor or EPC quote), used as is at every size and no longer sourced.
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- Ex-factory
- Installed
- Fully financed· this figure
Included
- Equipment and installation
- Indirect and owner's costs
- Contingency
Not included
- Nothing
Added at project level
- Nothing: project mode uses the figure as is
Project figures
Values passed to project mode when this asset is added to a project.
Combined-cycle gas turbine power plantConcept sketch, not to scale · drag to rotate
- Natural gas (HHV) in
- —
- Electricity (net) outMain product
- —
- CAPEX to the battery limit
- —
- Fixed O&M
- —
- Variable O&M, excluding feedstocks
- —
- Asset lifetime
- 30 years
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Levelised cost of electricity
A standalone indicator for a quick read. Project mode recomputes it for the whole system.
—
- LCOE - capital component—
- LCOE - fixed O&M component—
- LCOE - gas component—
- LCOE - CO2 allowance component—
- LCOE - variable O&M component—
Linked to the balance above
Equivalent hours per year at net capacity (capacity factor = hours / 8,760). Default 6,300 h is the ISE 2024 high (baseload) case for a CCGT; 3,000 h is the ISE low (mid-merit) case. Below 3,000 h a plant is a peaker and an OCGT is usually cheaper.
Extra fuel per MWh, in % of the full-load heat rate, that a plant running 0 full-load hours would burn; the model applies it in proportion to the hours not run: multiplier = 1 + penalty x (1 - capacity factor). Default 0 reproduces the full-load basis of both ISE and EIA. No source in this calculator gives a CCGT part-load or cycling penalty: enter your own figure from the OEM part-load curve or plant data if the plant will cycle.
Delivered gas price per MWh of fuel on an HHV basis, the same basis as the efficiency and the gas inlet. Default 38 EUR/MWh is the ISE 2024 gas price; ISE does not state its heating-value basis, so it is read as HHV (the OCGT calculator of the same series uses the same convention). If your price is per MWh LHV, divide it by 1.107.
Price paid per tonne of CO2 emitted (EU ETS allowance). Default 75 EUR/t is the ISE 2024 lower value; 90 EUR/t is the ISE higher value. Held constant over the life of the plant, unlike ISE, which applies a rising price path.
Real weighted average cost of capital, as a fraction (0.064 = 6.4 %). Real, because every cost here is in constant 2024 EUR. ISE 2024: 6.4 % real (8.2 % nominal) for CCGT and gas turbines alike.
Years over which the investment is annualised. ISE 2024: 30 years for CCGT.
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Benchmarks
This model's figures against published references and reference cases.
Reference cases at this size and usage
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All results
Every model output at the current settings, grouped, with the sensitivity charts.
53 outputs · 5 groups · 15 also shown above, dimmed
Levelised cost
11- Short-run marginal cost
- ComputingEUR/MWh
- Gas and CO2 share of LCOE
- Computing%
- LCOE at the ISE high CO2 price
- ComputingEUR/MWh
- LCOE at the ISE mid-merit hours
- ComputingEUR/MWh
- LCOE inside the ISE 2024 CCGT range
- Computingbool
Capital and O&M
17- Reference-case CAPEX at 627 MW
- ComputingEUR/kW
- Model CAPEX at this size
- ComputingEUR/kW
- CAPEX inside the ISE 2024 range
- Computingbool
- Total plant investment (MEUR)
- ComputingMEUR
- Capital recovery factor
- Computing1/year
- Annualised CAPEX
- ComputingEUR/year
- Fixed O&M rate
- ComputingEUR/kW/year
- Variable O&M rate
- ComputingEUR/MWh
- Capital and fixed cost per kW
- ComputingEUR/kW/year
- Variable O&M
- ComputingEUR/year
- Annual gas cost
- ComputingEUR/year
- Annual CO2 allowance cost
- ComputingEUR/year
- Total annual cost
- ComputingEUR/year
Performance
7- Net efficiency (HHV, full load)
- Computing%
- Net heat rate (HHV, full load)
- ComputingBtu/kWh
- Net efficiency (LHV equivalent)
- Computing%
- Gap to the ISE 2024 CCGT efficiency
- Computingpp
- Best EIA H-class efficiency
- Computing%
- Lowest EIA H-class efficiency
- Computing%
- Efficiency inside the EIA H-class range
- Computingbool
Operation and gas
12- Full-load hours
- Computingh/year
- Capacity factor
- Computing%
- Part-load heat-rate multiplier
- Computingratio
- Annual-average net efficiency (HHV)
- Computing%
- Specific fuel consumption (full load)
- ComputingMWh/MWh
- Effective fuel consumption (annual average)
- ComputingMWh/MWh
- Annual-average heat rate (HHV)
- ComputingBtu/kWh
- Annual gas consumption (MMBtu HHV)
- ComputingMMBtu/year
CO2
6- CO2 emission factor of the gas
- Computingt/MWh
- CO2 intensity of electricity
- Computingt/MWh
- Annual CO2 emissions
- Computingt/year
- CO2 intensity on the EIA study factor
- Computingt/MWh
- Emission factor vs EIA study factor
- Computing%
Sensitivities
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Sources
51 documented assumptions · 9 sources
- ise.fraunhofer.deFraunhofer ISE, Levelized Cost of Electricity - Renewable Energy Technologies (July 2024)CCGT CAPEX, O&M, WACC, lifetime, full-load hours, gas and CO2 prices, LCOE range, annuity method
- eia.govEIA / Sargent & Lundy, Capital Cost and Performance Characteristic Estimates (AEO2025), Table 1-2H-class combined cycles, heat rates (HHV), costs in 2023 USD, CO2 117 lb/MMBtu
- eia.govEIA / Sargent & Lundy, Capital Cost and Performance Characteristic Estimates (AEO2020)H-class combined-cycle heat rates
- eia.govEIA, Carbon Dioxide Emissions Coefficientsnatural gas 52.91 kg CO2/MMBtu
- eia.govEIA Energy Explained, British thermal units1 kWh = 3,412 Btu
- lazard.comLazard, Levelized Cost of Energy+ (June 2024, v17.0)gas combined cycle USD 45-108/MWh, plausibility bound only
- ieaghg.orgIEAGHG 2017-02, natural gas specification (HHV 51.473 / LHV 46.502 MJ/kg), for the LHV-equivalent efficiency only
- ecb.europa.euEuropean Central Bank, euro reference exchange rate, US dollar2023 average 1.0813 USD/EUR (EIA costs to EUR)
- ec.europa.euEurostat, HICPeuro area annual inflation 2024 of 2.4 % (2023 EUR to 2024 EUR)
About
Calculator context
About
Calculator context
A screening model of a gas turbine + heat recovery steam generator + steam turbine plant, built for a feasibility study that has to stand in front of a lender. Performance comes from EIA's H-class reference (627 MW net, 6,226 Btu/kWh HHV, i.e. 54.8 % HHV). Two sourced reference cases set the costs: Fraunhofer ISE's 2024 LCOE study (900-1,300 EUR/kW all-in CAPEX, 1,100 midpoint, 20 EUR/kW/year fixed and 5 EUR/MWh variable O&M) and EIA AEO2025's 1x1x1 H-class (USD 921/kW, 15.51/kW-year, 3.33/MWh in 2023 USD, i.e. 872 EUR/kW, 14.69 and 3.15 in 2024 EUR at the ECB 2023 rate and euro-area HICP). The CAPEX per kW follows a 0.91 scale exponent fitted on EIA's 627 MW and 1,227 MW H-class plants, or a customized all-in figure used as is; the fixed O&M per kW follows a 0.63 exponent from the same two plants (USD 15.51 and 12.12/kW-year). The economic basis is ISE's: gas at 38 EUR/MWh, CO2 at 75 EUR/t, 6.4 % real WACC, 30 years, 6,300 full-load hours. The same basis is used by the OCGT calculator of the series.
With the ISE case at the defaults the LCOE is 115.5 EUR/MWh: 13.2 capital, 3.2 fixed O&M, 69.3 gas, 24.7 CO2 and 5.0 variable O&M, inside the 109-181 EUR/MWh ISE prints for German CCGTs. At ISE's mid-merit 3,000 h it is 133.5 EUR/MWh; at the 90 EUR/t high CO2 price 120.4. The CO2 intensity is 0.329 t/MWh (EIA coefficient 52.91 kg/MMBtu), against 0.330 on the 117 lb/MMBtu of the EIA cost study.
Read it with its limits: a real annuity with constant output, prices and CO2 price (ISE's top end is higher because ISE lets the CO2 price rise), no start-up costs, no part-load or cycling heat-rate penalty unless the user enters one, no heat extraction, no capture. The full-load heat rate of the 627 MW EIA case (6,226 Btu/kWh) is applied at every size; EIA's 418 MW single-shaft case prints 6,431 Btu/kWh, about 3 % more fuel, so near 418 MW the LCOE reads roughly 2-3 EUR/MWh low. Plants below 418 MW net are out of scope: EIA costs no smaller H-class combined cycle, and smaller plants run F-class, industrial or aeroderivative turbines at a lower efficiency than the H-class heat rate used here. The CAPEX is all-in and exported as fully financed, so the project adds no further cost layer. Everything is on HHV; the ISE gas price is read as HHV because ISE does not state its basis.
Model
112 variables — inputs, calculations and outputs, with their dependencies.
Model
112 variables — inputs, calculations and outputs, with their dependencies.
| Variable | Value | Unit | Depends on |
|---|---|---|---|
| 627 | MW | — | |
| 6300 | h/year | — | |
| 0 | % | — | |
| 1 | — | — | |
| 0 | — | — | |
| 1100 | EUR/kW | — | |
| 38 | EUR/MWh | — | |
| 75 | EUR/t | — | |
| 0.064 | ratio | — | |
| 30 | years | — |
| Variable | Formula | Unit | Depends on |
|---|---|---|---|
if((<=)+(!=)*(!=)+(<)+(>)+(>=)*(<=)+(<=)+(>)+(<)+(<)+(<)+(>=)+(<)+(<)>,,) | bool | ||
/max(,) | EUR/USD | ||
if(==,*,) | EUR/kW/year | ||
+ln(/max(,))/ln(/max(,)) | — | ||
/max(,) | ratio | ||
*/max(,) | MMBtu/MWh | ||
* | kW | ||
+**(-/) | ratio |
| Variable | Formula | Unit | Depends on |
|---|---|---|---|
if(==,*,(+)/(+)) | EUR/kW | ||
*(/max(,))^(-) | EUR/kW/year | ||
if(==,*,) | EUR/MWh | ||
/max(,)* | % | ||
/max(*,) | Btu/kWh | ||
* | % | ||
- | pp | ||
/max(min(,,,),)* | % | ||
/max(max(,,,),)* | % | ||
if((>=-)*(<=+),,) | bool | ||
clamp(,,) | h/year | ||
/* | % | ||
+**(-*) | ratio | ||
/max(,) | % | ||
/max(*,) | MWh/MWh | ||
* | MWh/MWh | ||
* | Btu/kWh | ||
* | MW | ||
* | MWh/year | ||
* | MWh/year | ||
* | MMBtu/year | ||
*/max(,) | t/MWh | ||
* | t/MWh | ||
* | t/h | ||
* | t/year | ||
- | MWh/year | ||
***/max(*,) | t/MWh | ||
(*/max(,)-)* | % | ||
*(/max(,))^(-) | EUR/kW | ||
if(>=,,) | EUR/kW | ||
if((>=)*(<=),,) | bool | ||
* | EUR | ||
/max(,) | MEUR | ||
if(<,/max(,),(*(+)^)/max((+)^-,)) | 1/year | ||
* | EUR/year | ||
* | EUR/year | ||
(+)/max(,) | EUR/kW/year | ||
* | EUR/year | ||
* | EUR/year | ||
* | EUR/year | ||
+ | EUR/year | ||
+++ | EUR/year | ||
/max(,) | EUR/MWh | ||
/max(,) | EUR/MWh | ||
/max(,) | EUR/MWh | ||
/max(,) | EUR/MWh | ||
/max(,) | EUR/MWh | ||
/max(,) | EUR/MWh | ||
++ | EUR/MWh | ||
(+)/max(,)* | % | ||
-+* | EUR/MWh | ||
*/max(,)+(+*)**+ | EUR/MWh | ||
if((>=)*(<=),,) | bool |
Assumptions
51 assumptions used in the calculations
Assumptions
51 assumptions used in the calculations
Protects divisions against a zero denominator.
Market range Not applicable (numerical guard).
0.000001Numerical constantUsed in guards and flags, so no number is written inline.
Market range Not applicable (literal zero).
0Numerical constantUsed in the CRF, multipliers and flags.
Market range Not applicable (literal one).
1Numerical constantConverts fractions to percent.
Market range Exact by definition of percent.
100%Unit conventionConverts percent inputs to fractions.
Market range Exact (1/100).
0.011/%Unit conventionCapacity factor = full-load hours / 8,760; also the upper limit of the hours input.
Market range 8,760 (8,784 in a leap year).
8760h/yearCalendar conventionConverts MW to kW for per-kW costs.
Market range Exact (SI prefix kilo/mega).
1000kW/MWSI unit conversionConverts MWh to kWh in the Btu conversions.
Market range Exact (1 MWh = 1,000 kWh).
1000kWh/MWhSI unit conversionConverts kg of CO2 to tonnes.
Market range Exact (metric tonne).
1000kg/tSI unit conversionEfficiency = 3,412 / heat rate; heat rate = 3,412 / efficiency.
Market range 3,412.14 Btu/kWh unrounded (International Table Btu).
3412Btu/kWhEIA unit conventionConverts Btu to MMBtu for emission factors quoted per MMBtu.
Market range Exact (one million Btu).
1000000Btu/MMBtuUnit conventionConverts the EIA study's 117 lb CO2/MMBtu to kg.
Market range Exact (international pound).
0.453592kg/lbLegal unit definitionReports CAPEX in millions of EUR.
Market range Exact (one million).
1000000EUR/MEURUnit conventionIdentifier of the reference case 'Fraunhofer ISE LCOE 2024, Germany (costs) on the EIA H-class heat rate'.
Market range Not applicable.
1Selector identifierIdentifier of the reference case 'EIA AEO2025 case 6, CC 1x1x1 single shaft H class'.
Market range Not applicable.
2Selector identifierFixed O&M of the ISE reference case.
Market range EIA AEO2025 1x1x1: 14.69 EUR/kW/year (2024 EUR).
20EUR/kW/yearFraunhofer ISE LCOE 2024Variable O&M (excluding gas and CO2) of the ISE reference case.
Market range EIA AEO2025 1x1x1: 3.15 EUR/MWh (2024 EUR).
5EUR/MWhFraunhofer ISE LCOE 2024CAPEX of the EIA reference case, 2023 USD, total overnight; converted to 2024 EUR in the model.
Market range Case 5 2x2x1 H class: $868/kW at 1,227 MW.
921USD/kWEIA AEO2025 capital cost studyFixed O&M of the EIA reference case, 2023 USD.
Market range Case 5 2x2x1: $12.12/kW-year.
15.51USD/kW/yearEIA AEO2025 capital cost studyVariable O&M of the EIA reference case, 2023 USD.
Market range Case 5 2x2x1: $3.41/MWh.
3.33USD/MWhEIA AEO2025 capital cost studyConverts the EIA 2023 USD costs to EUR of the same year.
Market range Not applicable (official rate).
1.0813USD/EURECB reference rateIndexes the converted EIA costs from 2023 EUR to the 2024 EUR basis of the ISE case and of the meta.
Market range Not applicable (official index).
1.024ratioEurostat HICPDefault net capacity, and the reference size of the CAPEX scale law: the size of the EIA cost anchor (USD 921/kW). The ISE CAPEX, which ISE prints without a plant size, is placed at the same size.
Market range EIA H-class combined cycles: 627 MW (1x1x1) to 1,227 MW (2x2x1).
627MWEIA AEO2025 capital cost studyFull-load heat rate of both reference cases, and best of the four EIA H-class heat rates used as the efficiency range reference.
Market range EIA H-class 6,226-6,431 Btu/kWh across AEO2025 and AEO2020.
6226Btu/kWhEIA AEO2025 capital cost studySecond AEO2025 H-class point of the reference bracket.
Market range Single value for case 5 in the study.
6266Btu/kWhEIA AEO2025 capital cost studySets the low end of the EIA H-class efficiency bracket.
Market range Single value for the 2020 1x1x1 case.
6431Btu/kWhEIA AEO2020 capital cost studyFourth point of the EIA H-class bracket.
Market range Single value for the 2020 2x2x1 case.
6370Btu/kWhEIA AEO2020 capital cost studyDirect CO2 from burning pipeline natural gas, applied to the HHV fuel balance.
Market range Pipeline gas varies with composition; 117 lb/MMBtu in the EIA capital cost study.
52.91kg/MMBtuEIA CO2 emission coefficientsCross-check of the CO2 intensity: 117 lb/MMBtu x 6,226 Btu/kWh = 0.330 t/MWh.
Market range117lb/MMBtuEIA AEO2025 capital cost studyExponent 0.91 from the two H-class combined cycles that EIA costs in the same study, applied to the plant net capacity with the 627 MW cost anchor as reference size. The fit spans one shaft against two gas turbines on one steam turbine, which is how combined cycles grow in size; it is a two-point fit and is declared as such (medium). Outside 418-1,227 MW (the EIA cost points of both editions) the law is an extrapolation.
Market range 0.87 (AEO2020 pair) to 0.91 (AEO2025 pair).
0.91Derived from EIA AEO2025 Table 1-2 (two sizes), cross-checked on AEO2020Low end of the ISE range: sets the ISE reference-case CAPEX (midpoint 1,100 EUR/kW) and the CAPEX range flag.
Market range ISE 2024 CCGT: 900-1,300 EUR/kW.
900EUR/kWFraunhofer ISE LCOE 2024High end of the ISE range: sets the ISE reference-case CAPEX (midpoint 1,100 EUR/kW), the CAPEX range flag and the top of the customized CAPEX slider.
Market range ISE 2024 CCGT: 900-1,300 EUR/kW.
1300EUR/kWFraunhofer ISE LCOE 2024Used for the LCOE at the high CO2 price and as the top of the CO2 slider.
Market range ISE 2024: 75-90 EUR/t for 2024, rising afterwards in the ISE paths.
90EUR/tFraunhofer ISE LCOE 2024Hours of the mid-merit LCOE output and the bottom of the hours slider.
Market range ISE 2024 CCGT: 3,000-6,300 h/year.
3000h/yearFraunhofer ISE LCOE 2024Reference for the efficiency gap output only; the cost chain uses the EIA HHV heat rate. Not used as a case value because ISE does not state its heating-value basis.
Market range Single value printed for 2024.
60%Fraunhofer ISE LCOE 2024Numerator of the HHV/LHV ratio (1.107) behind the LHV-equivalent efficiency.
Market range Specific to the IEAGHG design gas (89 % methane); pure methane is 1.11.
51.473MJ/kgIEAGHG 2017-02 gas specificationDenominator of the HHV/LHV ratio.
Market range Depends on gas composition.
46.502MJ/kgIEAGHG 2017-02 gas specificationLower edge of the ISE range flag.
Market range ISE 2024 German CCGT: 109-181 EUR/MWh.
109EUR/MWhFraunhofer ISE LCOE 2024Upper edge of the ISE range flag.
Market range ISE 2024 German CCGT: 109-181 EUR/MWh.
181EUR/MWhFraunhofer ISE LCOE 2024LCOE = (CAPEX x CRF + fixed O&M + gas + CO2 + variable O&M) / annual net generation. Constant annual output and costs; no construction period, no degradation, no taxes.
Market range Not applicable (method).
—Fraunhofer ISE LCOE 2024Every cost is in constant 2024 EUR with no escalation, so the annuity uses the real rate (6.4 %). The nominal 8.2 % would only be correct with every cost line escalated; it is not used.
Market range ISE 2024: 6.4 % real / 8.2 % nominal; slider 0-7 % real.
—Fraunhofer ISE LCOE 2024Efficiency, gas price, gas inlet and emission factor are all on HHV, so no conversion is applied in the cost chain. If the ISE price is in fact per MWh LHV, the HHV price is 38 / 1.107 = 34.3 EUR/MWh and the LCOE falls by about 6.7 EUR/MWh at 54.8 % HHV.
Market range HHV/LHV of pipeline gas about 1.107 (IEAGHG design gas).
—Convention of this calculatorThe CO2 price is held constant over the plant life. ISE applies a path that rises well above 90 EUR/t by 2045, so for the same inputs ISE's upper LCOE is higher. Enter a levelised CO2 price if you need the rising path.
Market range ISE 2024 path: 75-90 EUR/t in 2024, 175-375 EUR/t by 2045.
—Simplification of this calculatorThe ISE figure is a total investment per kW, so the exported CAPEX is declared fully financed and the project adds no OSBL, indirect or contingency layer on top. Adding one would count those costs twice.
Market range Not applicable (boundary declaration).
—Convention of this calculatorThe EIA 1x1x1 costs are now the second reference case, converted to 2024 EUR at the ECB 2023 average of 1.0813 USD/EUR and indexed by the 2.4 % euro-area HICP of 2024: 872.2 EUR/kW, 14.69 EUR/kW/year, 3.15 EUR/MWh. They are US costs: they show what the same machine costs on a US basis, not a German one.
Market range EIA 872 EUR/kW (2024 EUR) against ISE 900-1,300 EUR/kW.
—EIA AEO2025 capital cost studyResults are checked against 40-200 EUR/MWh: the low end follows Lazard's US gas combined-cycle range, the high end ISE's German range plus margin. The input box is bounded so that no corner leaves it (capacity 418-1,500 MW, hours 3,000-8,000, both reference cases, customized CAPEX 820-1,300 EUR/kW, gas 20-60, CO2 0-90, WACC 0-7 %, life 25-40 years, part-load penalty 0-10 %).
Market range 40-200 EUR/MWh.
—Bounds of this calculatorNo source here gives a part-load or cycling heat-rate penalty for CCGT, so the penalty is a user input with a default of 0: at the default the annual-average efficiency equals the full-load one, the basis of both ISE and EIA. This is a limit of the model at the default: a plant that cycles or runs at part load burns more gas per MWh than shown, so the gas and CO2 components are a floor at low running hours unless the user enters a penalty.
Market range No independent range cited.
—Modelling choice, documentedExcluded: start-up fuel and costs, grid fees, heat extraction (CHP), CO2 capture, upstream methane emissions, decommissioning, taxes and construction interest. Ambient conditions are those of the source ratings (ISO). Out of scope: combined cycles below 418 MW net. The heat rate is EIA's H-class figure, and EIA's smallest H-class combined cycle is 418 MW (AEO2020); smaller plants are built on F-class, industrial or aeroderivative gas turbines at a lower efficiency, which this calculator does not represent, so the capacity input starts at 418 MW.
Market range Not applicable (scope).
—Scope of this calculatorIn a project the gas is an inlet priced by the project, so the gas cost is not exported as OPEX. CO2 allowances and variable O&M are exported as variable OPEX; fixed O&M as fixed OPEX; the all-in CAPEX as ISBL with a fully financed battery limit.
Market range Not applicable (chaining).
—OpenJack project conventionsFixed O&M of the larger EIA H-class case, used with case 6 to set how fixed O&M per kW falls with plant size.
Market range Case 6 1x1x1 (627 MW): $15.51/kW-year.
12.12USD/kW/yearEIA AEO2025 capital cost studyNet capacity of the larger EIA H-class case, second point of the fixed O&M size law (exponent 0.633, a two-point fit declared as such). The ISE fixed O&M carries no plant size, so it is scaled with the same EIA law from the 627 MW reference, as the CAPEX is.
Market range Case 6 1x1x1: 627 MW.
1227MWEIA AEO2025 capital cost study