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Autothermal Reforming (ATR) Hydrogen Plant — Screening Mass Balance & Cost (NETL-aligned)

Screening-stage ATR hydrogen calculator with annual/daily mass & energy balance and CAPEX/OPEX to levelized cost of hydrogen (LCOH).

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alexi

I do low-carbon energy stuff for 10 years & build things I wish existed.

Inputs

Design (full-load) hydrogen output at the plant battery limit. Used for CAPEX scaling and production calculations.

min 1000 · max 300000 · step 1000 · kg H2/day

Delivered natural gas price on an LHV energy basis.

EUR/MWh

Grid electricity price for imported power (e.g., ASU and auxiliaries).

EUR/MWh

Industrial make-up water cost (screening).

EUR/m3

Real discount rate used for CRF-based annualization.

ratio

Costs

Levelized cost of hydrogen (LCOH)

Total annual cost divided by annual hydrogen production

…EUR/kg H2

Installed plant cost (installed CAPEX)

Equipment purchase cost × installation factor (screening)

…EUR

Total OPEX (annual)

Fixed O&M + feedstock and utility costs

…EUR/year

Total equipment purchase cost (EPC, equipment-only)

Excludes installation, indirects, and owner’s costs

…EUR

Equipment cost — H2 purification (e.g., PSA)

Purification and product handling (equipment-only)

…EUR

Equipment cost — ATR reforming island

Reformer/reactor/heat recovery block (equipment-only)

…EUR

Equipment cost — ASU / oxygen supply

Major subsystem bucket (equipment-only)

…EUR

Equipment cost — Balance of plant (BoP) & utilities

Water/steam systems, cooling, power distribution, etc. (equipment-only)

…EUR

Results

Hydrogen production (annual)

Annualized from nameplate capacity and capacity factor

…kg H2/year

Hydrogen production (average day)

Annual production divided by 365

…kg H2/day

Natural gas energy input (annual)

Effective specific consumption × annual H2 production

…GJ NG/year

Natural gas energy input (average day)

Annual NG energy divided by 365

…GJ NG/day

Electricity consumption (annual)

Includes ASU and auxiliaries via a kWh/kg intensity factor

…MWh/year

Water consumption (annual)

Process/boiler feed make-up via a m3/kg intensity factor

…m3/year

CO2 produced (annual)

Uncaptured CO2 stream for no-CCS ATR

…tCO2/year

CO2 produced (average day)

Annual CO2 divided by 365

…tCO2/day

About

Calculator context

Introduction

This calculator provides a screening (pre-feasibility) estimate of an autothermal reforming (ATR) natural-gas-to-hydrogen plant’s mass/energy balance and cost metrics, including equipment purchase cost, installed plant cost, annual OPEX, and levelized cost of hydrogen (LCOH). It is conceptually aligned with the NETL comparative assessment of commercial fossil-based hydrogen technologies (NETL, 2022) and uses standard techno-economic practices commonly seen in IEA/IRENA/NREL-style models. Regional scope is global (no region-specific cost index is applied).

Methodology

The model converts a user-provided nameplate hydrogen capacity (kg/day) into annualized production using a capacity-factor framework, then applies intensity factors (feed/utility/CO2 per kg H2) with a part-load penalty, and finally computes costs using scaled specific CAPEX and fixed/variable OPEX.

Key formulas (variables defined in-line):

  • Utilization and part-load penalty
    • load_hours = hours_per_year × capacity_factor
    • load_penalty = clamp(1 + penalty_coeff × (1 − capacity_factor), 1, max_penalty)
  • Specific consumption with part-load
    • effective_consumption = specific_ng_consumption × load_penalty (units: GJ NG per kg H2)
  • Production and balances
    • H2_production_year = (H2_capacity_day / 24) × load_hours
    • NG_energy_year = effective_consumption × H2_production_year
    • CO2_year = (co2_factor × load_penalty) × H2_production_year
    • Electricity and water use are treated analogously via per-kg intensity factors.
  • Costing (standard project finance)
    • CRF = (r×(1+r)^n) / ((1+r)^n − 1)
    • specific_capex_scaled = clamp(C_ref × (capacity/capacity_ref)^exp, min, max)
    • Equipment purchase cost = specific_capex_scaled × capacity
    • Installed plant cost = equipment_cost × installation_factor
    • Annualized CAPEX = installed_cost × CRF
    • Fixed O&M = installed_cost × om_fraction_scaled
    • Total annual cost = annualized CAPEX + fixed O&M + feed/utility costs
    • LCOH = total annual cost / annual H2 production

Primary reference: NETL (2022) technology comparison report; scaling conventions and CRF are consistent with common practice in IEA/IRENA/NREL techno-economic analyses.

Applications

  • Business developer: rapid comparison of ATR project economics under different natural gas prices, capacity factors, and financing assumptions.
  • Strategy/BD team: portfolio screening of hydrogen supply options using LCOH and CO2 intensity outputs.
  • Process/tech lead (early stage): sanity-check of mass/energy balance magnitudes (NG, electricity, water, CO2) before deeper simulation or vendor quotes.

Model

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

74 variables shown of 74
VariableValueUnitDepends on
50000kg H2/day—
21.6EUR/MWh—
80EUR/MWh—
1EUR/m3—
0.08ratio—
VariableFormulaUnitDepends on
if((<=0)+(<0)+(<0)+(<0)+(<0)>0,1,0)bool
*h/year
clamp(+*(-),,)—
/max(,)kg H2/h
*GJ NG/kg H2
*kWh/kg H2
*kgCO2/kg H2
*kgCO2/year
/max(,)—
clamp(*^,,)EUR/(kg H2/day)
(*(+)^)/max(((+)^-),)—
*EUR/year
clamp(*^,,)1/year
*EUR/year
*/max(,)EUR/year
*EUR/year
*EUR/year
++EUR/year
VariableFormulaUnitDepends on
*kg H2/year
/max(,)kg H2/day
*GJ NG/year
/max(,)GJ NG/day
(*)/max(,)MWh/year
**m3/year
/max(,)tCO2/year
/max(,)tCO2/day
/max(,)—
(-)*GJ/year
*EUR
*EUR
*EUR
*EUR
*EUR
*EUR
+EUR/year
+EUR/year
/max(,)EUR/kg H2

Assumptions

32 assumptions used in the calculations

  • Prevents divide-by-zero in guarded denominators.

    Market range Not applicable

    0.000001
    Modeling constant

  • Used to convert capacity factor to annual load hours.

    Market range 8760 (non-leap year basis)

    8760h/year
    Calendar convention

  • Converts kg/day to kg/h for load-hour annualization.

    Market range 24

    24h/day
    Time conversion

  • Used for average daily quantities from annual totals.

    Market range 365 (screening basis)

    365day/year
    Calendar convention

  • Converts kWh to MWh.

    Market range 1000

    1000kWh/MWh
    Unit conversion

  • Converts MJ to GJ in LHV computations.

    Market range 1000

    1000MJ/GJ
    Unit conversion

  • Converts kg to metric tonnes.

    Market range 1000

    1000kg/t
    Unit conversion

  • Avoids inline numeric literals in DSL expressions.

    Market range 1

    1
    Numerical constant

  • Caps part-load consumption penalty to avoid unrealistic blow-ups at lower CFs.

    1.25
    Screening assumption

  • Represents increased specific consumption as capacity factor decreases (availability/part-load effects).

    0.15
    Screening assumption

  • Represents natural gas LHV energy input per kg H2 produced at full load (includes process fuel and reforming feed energy on a net basis).

    0.155GJ NG/kg H2
    Screening intensity factor (ATR, no CCS)

  • Represents imported electricity demand dominated by ASU power and auxiliaries at full load.

    1.5kWh/kg H2
    Screening intensity factor

  • Represents make-up water for steam generation and cooling system losses at full load.

    0.015m3/kg H2
    Screening intensity factor

  • Represents process CO2 produced per kg H2 for fossil reforming pathways without capture.

    9.2kgCO2/kg H2
    Screening emissions factor (direct CO2, no CCS)

  • Hydrogen lower heating value used for efficiency reporting.

    Market range 0.12

    0.12GJ/kg H2
    Thermochemical property

  • Defines the reference scale for CAPEX and O&M scaling curves.

    50000kg/day
    Model reference point

  • Represents total equipment purchase cost normalized by capacity at the reference size.

    600EUR/(kg H2/day)
    Screening CAPEX anchor (equipment-only)

  • Power-law scaling exponent for equipment CAPEX vs capacity.

    0.65
    Economies-of-scale heuristic

  • Prevents unrealistic low specific costs at very large scales within a simplified scaling model.

    300EUR/(kg H2/day)
    Model clamp bound

  • Prevents unrealistic high specific costs at very small scales within a simplified scaling model.

    1200EUR/(kg H2/day)
    Model clamp bound

  • Converts equipment purchase cost to installed plant cost (installed scope; excludes owner’s costs unless included by convention).

    1.7
    Installed-cost factor method

  • Approximate fraction of equipment purchase cost attributed to the ATR reforming island and heat recovery.

    0.35
    Screening cost breakdown

  • Approximate fraction of equipment purchase cost attributed to oxygen supply (ASU) for ATR.

    0.25
    Screening cost breakdown

  • Approximate fraction of equipment purchase cost attributed to purification (e.g., PSA) and product conditioning.

    0.15
    Screening cost breakdown

  • Approximate fraction of equipment purchase cost attributed to balance-of-plant utilities and offsites.

    0.25
    Screening cost breakdown

  • Represents labor, maintenance, overheads and routine replacements as a fraction of installed plant cost per year.

    0.041/year
    Screening fixed O&M fraction

  • Allows fixed O&M fraction to slightly decrease with plant scale.

    -0.05
    Economies-of-scale heuristic

  • Prevents unrealistically low fixed O&M at very large scales.

    0.0251/year
    Model clamp bound

  • Prevents unrealistically high fixed O&M at very small scales within a simplified model.

    0.061/year
    Model clamp bound

  • Capacity factor is fixed at 95% as per instruction.

    Market range 0.95

    0.95
    Instruction

  • Project lifetime is fixed at 15 years as per instruction.

    Market range 15

    15years
    Instruction

  • Converts MWh to GJ for price normalization.

    Market range 3.6

    3.6GJ/MWh
    Unit conversion

Sources

1 external source