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LCOA Calculator

Levelised cost of ammonia for green, blue, and grey production routes. Adjust parameters, compare scenarios, and analyse sensitivities. All calculations are performed locally in your browser.

Renewable electricity
Electricity cost LCOE of dedicated supply
$/MWh
Capacity factor Annual average utilisation
%
Electrolyser
Electrolyser capex Installed system cost
$/kW
Electrolyser efficiency System-level
kWh/kgH₂
Haber-Bosch synthesis
HB plant capex Per tonne annual capacity
$/tNH₃
Financing
Plant lifetime
years
WACC Simple mode: discount rate
%
Carbon pricing
Carbon price Applied to embedded emissions
$/tCO₂
Transport & storage
Transport & storage cost Optional; ex-works = 0
$/tNH₃
Green ammonia — LCOA
$—
per tonne NH₃ · ex-works
LCOA ($/GJ)
LHV basis (18.6 GJ/tNH₃)
Carbon cost impact
$0
at $0/tCO₂
Capex contribution
—%
of total LCOA
Feedstock contribution
—%
electricity / gas cost
Cost breakdown — $/tonne NH₃
Sensitivity analysis — ±20% variation on key parameters
Route comparison — current inputs vs all three routes
Saved scenarios — up to 3 cases for comparison
Slot 1 — empty
Configure inputs and click Save scenario below
Slot 2 — empty
Slot 3 — empty
Methodology. Simple mode uses a capital recovery factor (CRF). Advanced mode uses a full after-tax DCF with debt-equity split, loan tenor, and tax rate. Full equation derivations, default value sources, known limitations, and the review roadmap are in the methodology section below →
Methodology

How the calculator works

Full derivation of every equation used in this tool. The methodology is currently under active review as part of the Observatory's green ammonia pricing research programme — feedback and corrections are welcomed.

Under active review · Last updated June 2026 · Submit corrections to [email protected]

1 — Framework

The levelised cost of ammonia (LCOA) is the minimum price at which ammonia must be sold over a plant's lifetime to recover all costs including capital, operating expenditure, feedstock, and a required return on investment. It is expressed in real USD per tonne of NH₃ (ex-works unless transport costs are added).

The general LCOA formula is:

LCOA = (Annualised capex + Annual opex + Annual feedstock cost + Carbon cost + Transport) / Annual NH₃ production

All costs are expressed per tonne of ammonia produced annually at nameplate capacity. Two financing modes are available: Simple mode uses a capital recovery factor (CRF) to annualise capital costs; Advanced mode uses a full discounted cash flow (DCF) model with explicit debt and equity structure.

2 — Simple mode: capital recovery factor

The capital recovery factor converts a total capital expenditure into an equivalent uniform annual payment over the plant lifetime, given a discount rate (WACC). It is the standard approach used by IEA, IRENA, and CSIRO in published LCOA estimates.

CRF = WACC × (1 + WACC)ⁿ / ((1 + WACC)ⁿ − 1)
where n = plant lifetime in years, WACC = weighted average cost of capital (decimal)

Annualised capex per tonne of annual production capacity is then:

Capex_ann ($/tNH₃/yr) = Capex ($/tNH₃ capacity) × CRF

Fixed opex is expressed as a percentage of capex per year and added to the annualised capex. Variable opex (water, catalysts, consumables) is approximated within the fixed opex percentage for simple mode.

3 — Advanced mode: after-tax WACC and DCF

Advanced mode derives the after-tax WACC from explicit debt and equity parameters using the standard Modigliani-Miller formulation with the corporate tax shield on debt:

WACC_AT = D/(D+E) × Kd × (1 − T) + E/(D+E) × Ke
where D = debt fraction, E = equity fraction (= 1−D), Kd = cost of debt, Ke = cost of equity, T = corporate tax rate

The CRF is then recalculated using this after-tax WACC, replacing the single discount rate used in simple mode. Loan tenor is used to determine the debt service schedule but does not directly appear in the LCOA formula — it constrains the period over which the tax shield applies.

For the green route, advanced mode also adds an annualised stack replacement cost using a sinking fund factor (SFF). The SFF represents the annual contribution to a fund that accumulates to the replacement cost at the replacement interval:

SFF = WACC / ((1 + WACC)^n_stack − 1)
Stack_ann = Stack_capex × SFF × n_replacements
where n_stack = stack replacement interval (years), Stack_capex = replacement fraction × initial electrolyser capex ($/tNH₃), n_replacements = ⌊plant_life / n_stack⌋

Note: a known limitation of the current implementation is that the sinking fund approach slightly underestimates the true NPV cost of stack replacements occurring late in the plant life, as it does not account for the time value of money between replacement events. A full NPV treatment of each replacement event is on the roadmap for a future version.

4 — Green route equations

Green ammonia production combines water electrolysis (producing H₂) with air separation (producing N₂) and Haber-Bosch synthesis. The electricity cost dominates for most parameter combinations.

Electricity consumption per tonne NH₃:

H₂_required = 176.47 kg H₂ / tNH₃
(stoichiometric: 3H₂ + N₂ → 2NH₃; MW(H₂)=2, MW(NH₃)=17, ratio = 3×2/17×1000/1000 = 0.17647 tH₂/tNH₃ → 176.47 kgH₂/tNH₃)

Elec_per_tNH₃ = η_elec × H₂_required / 1000 (MWh/tNH₃)
where η_elec = electrolyser system efficiency in kWh/kgH₂ (system-level, including BoP losses)

Electricity cost component:

C_elec = LCOE ($/MWh) × Elec_per_tNH₃ (MWh/tNH₃)

Electrolyser capacity required (capacity sizing):

Elec_kW_per_tpa = Elec_per_tNH₃ × 1000 / (CF × 8760)
where CF = capacity factor (decimal), 8760 = hours per year
Elec_capex_per_tpa = Capex_elec ($/kW) × Elec_kW_per_tpa

Full green LCOA:

LCOA_green = C_elec
+ (Elec_capex_per_tpa × CRF) + (Elec_capex_per_tpa × 0.025) [electrolyser capex + opex]
+ Stack_ann [advanced mode only]
+ (HB_capex × CRF) + (HB_capex × opex_pct) [HB capex + opex]
+ C_N2 [N₂ separation, default $30/tNH₃]
+ C_transport

Carbon cost on green route: Lifecycle CO₂ emissions of green ammonia produced from renewable electricity are assumed to be approximately zero (upstream electricity emissions excluded under renewable energy certification). No carbon cost is therefore applied in the current model. A future version will allow users to input an upstream emissions factor for grid-connected electrolysers.

Known limitations (green route): (1) The model assumes dedicated renewable supply — grid-connected electrolysers with partial renewable matching are not yet supported. (2) HB synthesis electricity consumption (~0.5 MWh/tNH₃) is currently subsumed within the HB capex/opex term rather than modelled explicitly as a separate electricity draw — this is appropriate for dedicated supply but may slightly underestimate electricity costs for variable-CF configurations. (3) Water costs and desalination are not currently disaggregated. Both are on the review roadmap.

5 — Blue route equations

Blue ammonia uses steam methane reforming (SMR) or autothermal reforming (ATR) with carbon capture and storage (CCS). Natural gas is both feedstock and fuel. CCS captures a fraction of process CO₂; the remainder is unabated and subject to carbon pricing.

Gas cost:

C_gas = P_gas ($/GJ) × Cons_gas (GJ/tNH₃)
Default: 28 GJ/tNH₃ for SMR+HB (IEA 2023). ATR is typically 10–15% more efficient at ~24–26 GJ/tNH₃.

CCS cost:

CO₂_captured = CO₂_intensity (tCO₂/tNH₃) × CCS_rate
CO₂_unabated = CO₂_intensity × (1 − CCS_rate)
C_CCS = CO₂_captured × CCS_cost ($/tCO₂ captured)

Carbon cost (on unabated fraction):

C_carbon_blue = CO₂_unabated × P_carbon ($/tCO₂)

Full blue LCOA:

LCOA_blue = C_gas + (Capex_blue × CRF) + (Capex_blue × 0.04) + C_CCS + C_carbon_blue + C_transport
Fixed opex default: 4% of capex/yr (higher than green due to CCS maintenance)
Known limitations (blue route): (1) SMR and ATR are treated as having the same capex structure in simple mode; ATR's higher efficiency is not reflected in a lower gas consumption default unless the user overrides it in advanced mode. (2) CO₂ intensity default (1.8 tCO₂/tNH₃) reflects process emissions from SMR; combustion emissions for fuel gas are partially included. A full accounting including fugitive methane emissions upstream of the plant boundary is not yet implemented. (3) The model does not distinguish between geological storage costs and the cost of CO₂ utilisation (e.g. enhanced oil recovery), which can differ by 30–50%.

6 — Grey route equations

Conventional grey ammonia via SMR with no CCS. The grey route serves as the cost reference against which green and blue premiums are assessed. All CO₂ emissions are unabated and fully subject to carbon pricing.

C_gas_grey = P_gas × Cons_gas_grey [default: 26 GJ/tNH₃, slightly lower than blue due to no CCS energy penalty]
C_carbon_grey = CO₂_int_grey × P_carbon [default CO₂ intensity: 2.4 tCO₂/tNH₃, including process + partial combustion]

LCOA_grey = C_gas_grey + (Capex_grey × CRF) + (Capex_grey × opex_pct) + C_carbon_grey + C_transport
Fixed opex default: 3% of capex/yr
Note: The grey route default CO₂ intensity of 2.4 tCO₂/tNH₃ is consistent with IEA (2023) estimates for large-scale conventional SMR ammonia production, including process emissions and energy combustion within the plant boundary. Full lifecycle emissions including upstream methane leakage from gas supply (typically adding 0.3–0.8 tCO₂e/tNH₃ depending on supply chain) are not included in the default but can be approximated by increasing the CO₂ intensity input in advanced mode.

7 — Unit conversions and constants

NH₃ energy content
LHV = 18.6 GJ/tNH₃
HHV = 22.5 GJ/tNH₃
LHV basis used throughout
H₂ stoichiometry
176.47 kgH₂ / tNH₃
5.66 kgNH₃ / kgH₂
MW(NH₃) = 17.03 g/mol
$/tNH₃ → $/GJ
LCOA ($/GJ) = LCOA ($/tNH₃) / 18.6
e.g. $800/t → $43.0/GJ
Electrolyser capacity factor
8,760 hours/year
CF = annual output / (rated capacity × 8760)
Typical range: 30–60%

8 — Default parameter values and sources

Parameter Default Basis Source
LCOE (green)$45/MWhGlobal average utility-scale solar+wind hybrid 2024–25BloombergNEF 2024
Capacity factor45%Hybrid solar/wind dedicated supply, mid-latitudeIRENA 2022
Electrolyser capex (ALK)$850/kWInstalled system cost, large-scale alkaline, 2024–25IEA 2023; BNEF 2024
Electrolyser efficiency65 kWh/kgH₂System-level ALK incl. BoP, compression, dryingIEA 2023; CSIRO 2023
HB plant capex$500/tNH₃Large-scale green HB synthesis unit, 2023–24 engineering estimatesCSIRO 2023; Haldor Topsoe
WACC (green)8%Emerging market / greenfield project, 2024IEA 2023; Observatory estimate
Gas price (blue/grey)$8/GJMid-range global LNG netback / pipeline gas, 2025S&P Global 2025
CCS cost$80/tCO₂Point-source capture + transport + storage, 2024 estimatesGlobal CCS Institute 2023
CCS capture rate90%Post-combustion capture on SMR; process CO₂ typically higher rate achievableIEA 2023
CO₂ intensity (grey)2.4 tCO₂/tNH₃Plant boundary, process + energy combustion; excludes upstream methaneIEA 2023; IPCC AR6
Plant lifetime25 yearsStandard assumption for large industrial plant financingIndustry convention

9 — Review status and roadmap

This calculator is in active development as part of the Observatory's green ammonia pricing research workstream. The following items are currently under review or planned for future versions:

Under active review
  • Full NPV treatment of electrolyser stack replacements
  • Explicit HB electricity consumption as a separate input
  • Grid-connected electrolyser mode with grid emissions factor
  • Upstream methane leakage inclusion in blue/grey CO₂ intensity
  • Water and desalination cost disaggregation
  • Variable opex escalation over plant life
Planned for future versions
  • Coal gasification route (relevant for China and India)
  • Biomass gasification with CCS (BiCCS)
  • RFNBO certification cost premium input
  • Regional cost presets (Middle East, Australia, India, Europe)
  • Export scenario with shipping cost model
  • Downloadable PDF / CSV output of results
  • Historical LCOA benchmark comparison overlay

The Observatory welcomes corrections to default values, methodology feedback, and suggestions for additional routes or parameters from researchers, project developers, and practitioners in the sector.

Submit methodology feedback → See research programme →

Ammonia Observatory LCOA Calculator. Results are indicative estimates based on user inputs and standard engineering assumptions. Not a substitute for project-level feasibility analysis. Default values sourced from IEA (2023), IRENA (2022), CSIRO (2023), and BloombergNEF (2024). Corrections and methodology feedback to [email protected].