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Hydrogen-ready centrifugal pipeline compressor (natural gas to 100 % H2)

Electric-driven centrifugal recompression station on a gas transmission line, for natural gas, H2 blends or pure hydrogen: blend properties, polytropic head, number of impellers and casings, gas and energy flow at rated power, compression energy as a share of the energy carried, and a compression service cost per MWh (LHV) from the European Hydrogen Backbone 2020 cost data.

  • CurrencyEUR 2020
  • Battery limitfully financed
  • 68 documented assumptions
  • Updated2 Nov 2026

Mass and energy balance

What the asset draws and delivers for the case and load you choose.

Reference case

capacity factor: 57.1 %

Equivalent hours a year at rated power. Default 5,000 h, the EHB load factor for compressor electricity (Table 3). It spreads the capex over the energy carried and is what project mode will set.

Flows

  • In: Hydrogen in the gas (suction)—
  • In: Natural gas in the gas (suction)—
  • In: Electricity (compressor drive)—

Asset

Hydrogen-ready centrifugal pipeline compressor station

  • Out: Hydrogen in the gas (discharge, recompressed)—
  • Out: Natural gas in the gas (discharge, recompressed)—

Annual quantities at the current usage.

Rated electrical input of the variable-speed electric drive (MWe), the basis of the EHB station capex. Default 10 MW. The slider runs from 1 to 50 MW, which covers the catalogue machines (Everllence MOPICO about 5 MW, Ebara Elliott 140TCH 10 to 35 MW). The station runs at this power during its full-load hours.

Gas mass flow at rated power
— kg/s
Gas flow at rated power (normal volume)
— Mm3/day
Energy flow through the station
— MW
Number of impellers
— -

CAPEX

Specific cost at this size, what backs it, and how it behaves with scale.

Specific CAPEX at this size

—

Reference size 10 MW

EHB Figure 6 and Table 5.

Model value uses the EHB reference case. Customized replaces it with your own figure (a vendor quote, for instance), at every size; the CAPEX is then no longer sourced.

Model station CAPEX per kW by rated electrical drive power

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  1. Ex-factory
  2. Installed
  3. Fully financed· this figure
CAPEX at the battery limit—

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.

Concept sketch, not to scale · drag to rotate

Hydrogen in the gas (suction) in
—
Natural gas in the gas (suction) in
—
Electricity (compressor drive) in
—
Hydrogen in the gas (discharge, recompressed) outMain product
—
Natural gas in the gas (discharge, recompressed) out
—
CAPEX to the battery limit
—
Fixed O&M
—
Variable O&M, excluding feedstocks
0 EUR/year
Asset lifetime
25 years

Log in to add this asset to a project.

Compression cost per MWh transported

A standalone indicator for a quick read. Project mode recomputes it for the whole system.

—

  • Capital part—
  • Fixed O&M part—
  • Electricity part—

Linked to the balance above

capacity factor: 57.1 %

Equivalent hours a year at rated power. Default 5,000 h, the EHB load factor for compressor electricity (Table 3). It spreads the capex over the energy carried and is what project mode will set.

Hydrogen share of the gas, in mole (volume) percent: 0 is natural gas, 100 is pure hydrogen. Blend properties are mixed on a molar basis from the Brun (Elliott, NETL 2022) property table.

Discharge over suction pressure of the station. Default 1.3, the Elliott pipeline recompression case. Range 1.2 to 1.4 for pipeline recompression (Brun slide 4), up to 1.6 for the Xiao et al. 2025 two-stage machine.

Gas temperature at the compressor inlet. Default 294.3 K (70 F), the condition of the Brun property table. The head rises in proportion to it.

Price of the electricity driving the compressor. Default 50 EUR/MWh, the EHB medium value (EHB range 40 to 90).

Rate used to annualise the capex. Costs are constant 2020 euros with no escalation, so it is applied as a real rate. Default 6 %, the middle of the EHB 5 to 7 % WACC.

Service life of the compressor station, over which the capex is annualised. Default 25 years, inside the EHB 15 to 33 year depreciation period for compressors.

Compression cost per MWh transported by full-load hours

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Benchmarks

This model's figures against published references and reference cases.

Number of impellers, -

2 Xiao et al. 2025, section 2.1.

8 Brun slide 9.

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.

57 outputs · 6 groups · 14 also shown above, dimmed

Compression cost

11
Compression cost per MWh transported
ComputingEUR/MWh
Capital part
ComputingEUR/MWh
Fixed O&M part
ComputingEUR/MWh
Electricity part
ComputingEUR/MWh
Electricity share of the compression cost
Computing%
Compression cost per tonne of gas
ComputingEUR/t
Capital recovery factor
Computing1/year
Annualised CAPEX
ComputingEUR/year
Fixed O&M
ComputingEUR/year
Electricity cost
ComputingEUR/year
Total annual cost
ComputingEUR/year

Compressor

11
Polytropic head
ComputingkJ/kg
Number of impellers
Computing-
Number of casings
Computing-
Impeller loading
Computing%
Impellers with high-speed design
Computing-
Implied impeller head coefficient
Computing-
Natural-gas head at the same duty
ComputingkJ/kg
Head ratio to natural gas
Computing-
Tip speed ratio to keep the impeller count
Computing-
Discharge temperature
ComputingK
Temperature rise across the station
ComputingK

Gas properties

5
Blend molar mass
Computingg/mol
Hydrogen share by mass
Computing%
Blend isentropic exponent
Computing-
Blend compressibility factor
Computing-
Blend lower heating value
ComputingMJ/kg

Flow and energy

20
Gas mass flow at rated power
Computingkg/s
Gas mass flow (t/h)
Computingt/h
Gas flow at rated power (normal volume)
ComputingMm3/day
Energy flow through the station
ComputingMW
Compression energy, share of energy transported
Computing%
Specific electricity consumption
ComputingkWh/MWh
Shaft power
ComputingMW
Drive losses
ComputingMW
Gas power (polytropic)
ComputingMW
Heat and losses
ComputingMWh/year
Full-load hours
Computingh/year
Capacity factor
Computing%
Annual electricity
ComputingMWh/year
Annual energy transported
ComputingMWh/year
Annual energy transported (TWh)
ComputingTWh/year
Annual gas transported
Computingt/year
Annual hydrogen transported
Computingt/year
Annual natural gas transported
Computingt/year
Line length served, at the high EHB rate
Computingkm
Line length served, at the low EHB rate
Computingkm

CAPEX

6
Station CAPEX
ComputingEUR
Model station CAPEX per kW
ComputingEUR/kW
Station CAPEX per kW used
ComputingEUR/kW
Comparable NG compressor CAPEX, low
ComputingEUR/kW
Comparable NG compressor CAPEX, high
ComputingEUR/kW
CAPEX per kW of energy transported
ComputingEUR/kW

Cross-checks

4
Cross-check: NG impellers at PR 1.6
Computing-
Cross-check residual (NG)
Computing-
Calibration point: H2 impellers at PR 1.3
Computing-
Calibration residual (H2)
Computing-

Sensitivities

6 charts
Compression cost components vs full-load hours

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Compression cost and impellers vs hydrogen share

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Compression energy share and head vs pressure ratio

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Compression cost by EHB case (1 low, 2 medium, 3 high)

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Compression cost vs electricity price

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Gas flow vs rated drive power

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About

Calculator context

Models one electric-driven centrifugal compressor station on a transmission pipeline, from 1 to 50 MW of rated electrical drive power, carrying natural gas, a natural gas and hydrogen blend (0 to 100 % H2 by volume) or pure hydrogen. The blend properties (molar mass, heat capacity, compressibility, lower heating value) are mixed on a molar basis from the Brun (Elliott Group, NETL 2022) property table, which takes them from NIST REFPROP; the two compressibility factors are derived from the densities Brun prints, not printed themselves. The polytropic head follows from the station pressure ratio (1.2 to 1.6), the suction temperature and an 80 % polytropic efficiency (DOE 2014, Concepts NREC).

The number of impellers is the head divided by what one conventional 1200 ft/s impeller can give. That limit, 44 kJ/kg, is calibrated on a single anchor: Elliott's pure-hydrogen recompression case at PR 1.3, which needs 8 impellers. With that value an independent natural-gas machine, the two-stage Rolls-Royce pipeline compressor of Xiao et al. 2025 at PR 1.6, also comes out at 2 impellers; that is an indicative cross-check, not a validation. For the same pressure ratio hydrogen needs about ten times the head of natural gas, so at the same tip speed it needs eight to nine times the impellers. The 'about three times' often quoted is the tip speed needed to keep the impeller count, which the calculator also shows.

At rated power the shaft power (94 % drive efficiency, ABB) sets the mass flow, the energy flow (LHV) and the compression energy as a share of the energy carried. The economics use the European Hydrogen Backbone 2020 (Table 5): station capex of 2.2, 3.4 or 6.7 MEUR per MWe, fixed O&M of 0.8 to 1.7 % of capex, the electricity price, the WACC and the compressor depreciation period, all in constant 2020 euros. The EHB cost equation is linear in MWe, so the cost per MWh does not depend on the station size: it moves with the hydrogen share, the pressure ratio, the full-load hours and the prices. The brief asked for HHV; no sourced HHV pair was found, so the energy basis is LHV, as in the EHB. Only an electric drive is modelled: the EHB assumes electric compressors and no sourced gas-turbine driver efficiency was found.

Model

136 variables — inputs, calculations and outputs, with their dependencies.

136 variables shown of 136
VariableValueUnitDepends on
10MW—
100%—
1.3-—
294.3K—
2——
0——
3400EUR/kW—
5000h/year—
50EUR/MWh—
6%—
25years—
VariableFormulaUnitDepends on
if((<=0)+(<0)+(>)+(<)+(>)+(<=0)+(<)+(>)+(<0)+(>)+(<=0)+(<=0)+(>)+(<0)+(<0)+(>)+(<=0)>0,1,0)bool
*—
(**+(-)**)/max(,)kJ/(kg.K)
/max(,)kJ/(kg.K)
(-)/max(*,)—
**/kJ/kg
/kJ/(kg.K)
/(-)—
(-)/(*)—
**/*(^-)kJ/kg
/kJ/(kg.K)
/(-)—
(-)/(*)—
**/*(^-)kJ/kg
if(==,,if(==,,))*EUR/kW
if(==,,)%/year
*—
VariableFormulaUnitDepends on
*+(-)*g/mol
*/max(,)*%
/max(-,)-
*+(-)*-
(**+(-)**)/max(,)MJ/kg
**/max(,)*(^-)kJ/kg
*^K
-K
max(,ceil(/))-
max(,ceil(/))-
/max(*,)*%
*/max(*,)-
max(,ceil(/max(,)))-
**/*(^-)kJ/kg
/max(,)-
sqrt()-
max(,ceil(/))-
--
max(,ceil(/))-
--
*MW
-MW
*MW
**/max(,)kg/s
*/t/h
/max(,)****Mm3/day
*MW
/max(,)*%
*/max(,)kWh/MWh
/*km
/*km
clamp(,0,)h/year
/*%
*MWh/year
*MWh/year
*TWh/year
*t/year
**t/year
max(0,-)t/year
(+*(-))*MWh/year
clamp(*(/)^(-),*,*)EUR/kW
if(>=,,)EUR/kW
**EUR
/(*)EUR/kW
/(*)EUR/kW
/max(*,)EUR/kW
if(<,/,(*(+)^)/max((+)^-,))1/year
*EUR/year
**EUR/year
*EUR/year
++EUR/year
/max(,)EUR/MWh
/max(,)EUR/MWh
/max(,)EUR/MWh
++EUR/MWh
/max(,)EUR/t
/max(,)*%

Assumptions

68 assumptions used in the calculations

  • Prevents division by zero.

    Market range Not applicable (numerical parameter).

    0
    Numerical stability constant.
  • Upper limit of full-load hours and capacity-factor basis.

    Market range 8760 (8784 in a leap year).

    8760h/year
    Calendar convention.
  • Converts kg/s to kg/h.

    Market range Exact.

    3600s/h
    Unit conversion.
  • Unit value used in mixing rules, guards and the CRF.

    Market range Exact.

    1
    Unit conversion.
  • Converts a percent into a fraction.

    Market range Exact.

    0.01
    Unit conversion.
  • Converts a fraction into a percent; also the 100 % upper guard of percent inputs.

    Market range Exact.

    100%
    Unit conversion.
  • Converts MW into kW.

    Market range Exact.

    1000kW/MW
    Unit conversion.
  • Converts a head in kJ/kg into J/kg to compare with a tip speed squared (m2/s2).

    Market range Exact.

    1000J/kJ
    Unit conversion.
  • Converts kg into tonnes.

    Market range Exact.

    1000kg/t
    Unit conversion.
  • Converts MWh into TWh.

    Market range Exact.

    0.000001TWh/MWh
    Unit conversion.
  • Converts the EHB capex in MEUR per MWe into EUR per kWe.

    Market range Exact.

    1000(EUR/kW)/(MEUR/MW)
    Unit conversion.
  • Converts an hourly volume into a daily volume.

    Market range Exact.

    24h/day
    Unit conversion.
  • Converts m3 into million m3.

    Market range Exact.

    0.000001Mm3/m3
    Unit conversion.
  • Specific gas constant of the mixture R_s = R/M.

    Market range Exact (CODATA 2018).

    8.314462kJ/(kmol.K)
    Physical constant.
  • Converts the molar flow into a normal volume flow (Nm3), ideal-gas basis.

    Market range 22.414 m3/kmol at 0 degC; 23.645 at 15 degC (standard m3).

    22.414m3/kmol
    Physical constant, ideal-gas reading of normal cubic metres.
  • Molar mass of hydrogen in the molar mixing rule.

    Market range 2.016 g/mol exact; Brun rounds to 2.

    2g/mol
    Brun slide 5, NIST REFPROP property table.
  • Molar mass of the natural gas of the Brun table, mostly methane with some ethane.

    Market range 16 (pure methane) to about 19 for rich gases.

    16.8g/mol
    Brun slide 5, Gulf Coast Gas composition.
  • Mass heat capacity of hydrogen, mixed on a molar basis to get the isentropic exponent.

    Market range 14.3 to 14.5 kJ/kgK near ambient.

    14.3kJ/(kg.K)
    Brun slide 7.
  • Mass heat capacity of the natural gas.

    Market range 2.2 to 2.5 kJ/kgK at pipeline pressure.

    2.3kJ/(kg.K)
    Brun slide 7.
  • Lower heating value of hydrogen: the energy basis of the transported energy, as in the EHB (LHV).

    Market range 119.9 to 120.0 MJ/kg (LHV); 141.8 MJ/kg on HHV.

    120MJ/kg
    Brun slide 5, converted from Btu/lbm.
  • Lower heating value of the natural gas of the Brun table.

    Market range 47 to 50 MJ/kg LHV depending on composition.

    48.88MJ/kg
    Brun slide 5, converted from Btu/lbm.
  • Compressibility of hydrogen at pipeline conditions, used in the polytropic head.

    Market range 1.03 to 1.05 at 50 to 80 bar and ambient temperature.

    1.035
    Derived from the REFPROP density printed by Brun.
  • Compressibility of the natural gas at pipeline conditions.

    Market range 0.85 to 0.90 at 50 to 80 bar and ambient temperature.

    0.869
    Derived from the REFPROP density printed by Brun.
  • Temperature of the Elliott reference case, used only for the calibration check at 8 impellers.

    Market range Pipeline suction 280 to 320 K.

    294.3K
    Brun slide 5 conditions.
  • Pressure ratio of the Elliott reference case, used for the calibration check; also the default of the pressure ratio input.

    Market range Pipeline recompression PR 1.2 to 1.4 (Brun slide 4).

    1.3
    Brun slide 9.
  • Lower limit of the pressure ratio input.

    Market range 1.2 to 1.4 (Brun).

    1.2
    Brun slide 4.
  • Upper limit of the pressure ratio input; beyond it the model leaves the cited recompression range.

    Market range 1.6 (Xiao) above the 1.2 to 1.4 of Brun.

    1.6
    Xiao et al. 2025, section 2.1.
  • Polytropic efficiency of the compressor, used in the polytropic exponent and to turn head into shaft work.

    Market range 0.78 to 0.85 for pipeline centrifugal compressors.

    0.8
    DOE Hydrogen Program 2014 progress report, Results.
  • Electrical-to-shaft efficiency of the variable-speed electric drive (transformer, converter, motor).

    Market range 0.94 to 0.96 for high-speed electric drives.

    0.94
    ABB ISMB-7 paper, section 'Higher efficiency'.
  • Tip speed of a conventional steel impeller, used to show the implied head coefficient.

    Market range 300 to 400 m/s for conventional pipeline impellers.

    365.8m/s
    Brun slide 9, converted from ft/s.
  • Tip speed of the high-speed design, used for the impeller count of a high-speed machine.

    Market range Development target; DOE/Concepts NREC kept tip speed below 2,100 ft/s.

    731.5m/s
    Brun slide 9, converted from ft/s.
  • Reference impeller count for the calibration check and benchmark of the impeller count.

    Market range 8 impellers in 1 to 2 casings (Elliott).

    8-
    Brun slide 9.
  • Maximum polytropic head per conventional impeller; sets the impeller count.

    Market range Equivalent to a head coefficient psi = h/U2 of about 0.33 at 365.8 m/s; typical pipeline impellers 0.3 to 0.5.

    44kJ/kg
    Calibration on the Elliott pure-H2 recompression case.
  • Sets the number of casings from the impeller count.

    Market range 8 to 10 impellers per between-bearings casing.

    8-
    Brun slide 9.
  • Pressure ratio of the independent NG cross-check.

    Market range Single real machine.

    1.6
    Xiao et al. 2025, section 2.1.
  • Stage count of the real NG compressor used as cross-check and benchmark.

    Market range Single real machine.

    2-
    Xiao et al. 2025, section 2.1.
  • Specific station capex of the EHB low case.

    Market range 2.2 / 3.4 / 6.7 MEUR/MWe (EHB low / medium / high).

    2.2MEUR/MW
    EHB Table 5.
  • Specific station capex of the EHB medium case (default).

    Market range 2.2 / 3.4 / 6.7 MEUR/MWe (EHB low / medium / high).

    3.4MEUR/MW
    EHB Table 5.
  • Specific station capex of the EHB high case.

    Market range 2.2 / 3.4 / 6.7 MEUR/MWe (EHB low / medium / high).

    6.7MEUR/MW
    EHB Table 5.
  • Exponent 1: the EHB cost equation scales linearly with capacity, with no economy of scale. The model applies the source law as written instead of inventing a sub-linear exponent.

    Market range Six-tenths rules are common for single machines, but none was found for H2 pipeline stations.

    1
    EHB Figure 6 and Table 5.
  • Reference size of the scaling law. With an exponent of 1 it has no effect on the result.

    Market range EHB stations 190 to 330 MWe per 1000 km of line.

    10MW
    Default station size of this calculator.
  • Lower ratio, used to show the capex of a comparable NG-only compressor.

    Market range 140 to 180 %.

    140%
    EHB Table 4.
  • Upper ratio, used to show the capex of a comparable NG-only compressor.

    Market range 140 to 180 %.

    180%
    EHB Table 4.
  • Fixed O&M of the EHB low case (lower end of the EHB range; the pairing with the low capex is a modelling choice).

    Market range 0.8 to 1.7 %/year.

    0.8%/year
    EHB Table 5.
  • Fixed O&M of the EHB medium and high cases (upper end of the EHB range; the pairing is a modelling choice).

    Market range 0.8 to 1.7 %/year.

    1.7%/year
    EHB Table 5.
  • Code of the EHB low case.

    Market range Not applicable.

    1
    Selector constant.
  • Code of the EHB medium case (default).

    Market range Not applicable.

    2
    Selector constant.
  • Code of the EHB high case.

    Market range Not applicable.

    3
    Selector constant.
  • Low end of the EHB compression energy rate, used to derive the line length one station serves.

    Market range 1.5 to 2.3 % per 1000 km (EHB).

    1.5%/1000 km
    EHB p.12.
  • High end of the EHB compression energy rate.

    Market range 1.5 to 2.3 % per 1000 km (EHB).

    2.3%/1000 km
    EHB p.12.
  • The 1000 km of line over which the EHB expresses its compression energy rate.

    Market range Exact.

    1000km
    Unit conversion.
  • Default of the electricity price input (EHB medium).

    Market range 40 / 50 / 90 EUR/MWh (EHB low / medium / high).

    50EUR/MWh
    EHB Table 5.
  • EHB low electricity price.

    Market range 40 to 90 EUR/MWh.

    40EUR/MWh
    EHB Table 5.
  • EHB high electricity price.

    Market range 40 to 90 EUR/MWh.

    90EUR/MWh
    EHB Table 5.
  • Default of the full-load hours input.

    Market range No independent range cited; the slider spans 4000 to 8000 h.

    5000h/year
    EHB Table 3.
  • Default of the discount rate input. The EHB does not say whether its WACC is real or nominal; all costs here are constant 2020 euros with no escalation, so the rate is applied as a real rate.

    Market range 5 to 7 % (EHB).

    6%
    EHB Table 5.
  • Lower EHB WACC.

    Market range 5 to 7 %.

    5%
    EHB Table 5.
  • Upper EHB WACC.

    Market range 5 to 7 %.

    7%
    EHB Table 5.
  • Default service life of the station, inside the EHB range.

    Market range 15 to 33 years (EHB).

    25years
    EHB Table 5.
  • Lower EHB compressor depreciation period.

    Market range 15 to 33 years.

    15years
    EHB Table 5.
  • Upper EHB compressor depreciation period.

    Market range 15 to 33 years.

    33years
    EHB Table 5.
  • Lower EHB station spacing, to read the implied spacing output against.

    Market range 100 to 600 km.

    100km
    EHB Table 3.
  • Upper EHB station spacing.

    Market range 100 to 600 km.

    600km
    EHB Table 3.
  • Molar mass, heat capacity, compressibility and heating value of the blend are mixed on a molar basis from the two pure gases. Linear molar mixing of Z is an approximation; real blends deviate by a few tenths of a percent at pipeline pressure.

    Market range Not applicable.

    —
    Modelling assumption.
  • Polytropic head H_p = Z.R_s.T_s/sigma x (PR^sigma - 1), with sigma = (k-1)/(k.eta_p). Z and k are taken at suction and held constant through the compression.

    Market range Not applicable.

    —
    Standard polytropic compression model.
  • One electric-driven compressor station; the EHB capex is a station-level planning figure, taken as all-in, so project mode adds no build-up (battery_limit fully_financed). The pipeline itself, gas-turbine drives, coolers' water and the value of the gas carried are outside the boundary.

    Market range Not applicable.

    —
    Scope choice.
  • All costs are constant 2020 euros with no escalation; the discount rate is applied as a real rate.

    Market range Not applicable.

    —
    Real-terms convention.
  • The station is H2-ready, so the H2 station capex applies at every blend, including 0 % H2. The capex of a comparable NG-only compressor is shown separately using the EHB 140-180 % ratio.

    Market range Not applicable.

    —
    Scope choice.