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Liquid hydrogen storage tank with boil-off management

Vacuum-insulated liquid hydrogen tank, 10 to 50,000 m3: stored mass, boil-off rate scaled on measured NASA and Linde tanks, yearly losses, vessel CAPEX from the DOE 68 m3 anchor, and storage cost per kg delivered with the boil-off vented, reused or reliquefied.

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Open Jack

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  • CurrencyEUR 2022
  • Battery limitex-factory
  • 52 documented assumptions
  • Updated27 Oct 2026

Mass and energy balance

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

Reference case

Days for one full turnover of the inventory: the tank delivers its contents once per period. 7 days is the UC Davis one-week case. Longer holding means fewer kg delivered a year for the same tank and the same boil-off.

Flows

  • In: Liquid hydrogen—
  • In: Electricity for reliquefaction—

Asset

Liquid hydrogen storage tank (vacuum-insulated, with boil-off management)

  • Out: Liquid hydrogen delivered—
  • Out: Boil-off gas reused (gaseous hydrogen)—

Annual quantities at the current usage.

Inner volume of the tank, the capacity the catalogue binds on. 3,218 m3 is the NASA LC-39 sphere. Reference products cover 11-114 m3 (Gardner station tanks) and 2,500-11,200 m3 (Kawasaki, NASA); between 114 and 2,500 m3 and above 11,200 m3 the calculator extrapolates.

Stored LH2 mass
— t
Usable liquid volume
— m3
Average send-out rate
— kg/h

CAPEX

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

Specific CAPEX at this size

—

Reference size 68 m3

NREL 1998, p. 20

Model value: the DOE 68 m3 vessel price scaled with a 0.7 exponent to your volume. Customized: your own quote per m3, used as is at every size; the value is then no longer sourced.

Specific CAPEX by geometric volume

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  1. Ex-factory· this figure
  2. Installed
  3. Fully financed
CAPEX at the battery limit—
Installation, civil works, engineeringproject level
Working capital, contingencyproject level

Included

  • Equipment as delivered by the manufacturer

Not included

  • Installation, piping and electrical works
  • Civil works, buildings and land
  • Engineering and construction
  • Contingency

Added at project level

  • Every installation and indirect cost layer, from the project settings
  • Contingency, from the project settings

Project figures

Values passed to project mode when this asset is added to a project.

Concept sketch, not to scale · drag to rotate

Liquid hydrogen in
—
Electricity for reliquefaction in
—
Liquid hydrogen delivered outMain product
—
Boil-off gas reused (gaseous hydrogen) out
—
CAPEX to the battery limit
—
Fixed O&M
—
Variable O&M, excluding feedstocks
0 EUR/year
Asset lifetime
25 years

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Storage cost per kg delivered

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

—

  • Storage cost: capital—
  • Storage cost: O&M—
  • Storage cost: boil-off—

Linked to the balance above

Days for one full turnover of the inventory: the tank delivers its contents once per period. 7 days is the UC Davis one-week case. Longer holding means fewer kg delivered a year for the same tank and the same boil-off.

Liquid share of the geometric volume. 95 % is the maximum of the Linde spec in DOE ST235; NASA keeps at least 10 % ullage (90 %).

Vent: the molecule and its liquefaction work are lost. Reuse: the gas is used on site at the gaseous hydrogen value, only the liquefaction work is lost. Reliquefaction: the gas returns to the tank at the cost of electricity; reliquefier CAPEX not included.

Value of a kg of gaseous hydrogen. Default 4.90 EUR/kg, the ACER estimate for alkaline electrolysis on 30/06/2025 (SMR 1.90, RFNBO 8.00).

Cost of liquefying a kg upstream. Default 1.14 EUR/kg, the UC Davis 2024 $1.2/kg for a large plant at 1.053 USD/EUR.

Electricity price for reliquefaction. Default 183.7 EUR/MWh, the EU non-household average excluding VAT, second half of 2025 (Eurostat). No effect in the other modes.

Real rate of the capital recovery factor on constant-euro costs. Default 10 %, the Argonne figure. A zero rate is accepted (CRF = 1/n).

Service and economic life of the tank. Default 25 years (Argonne); the NASA spheres have run since the 1960s.

Storage cost per kg delivered by holding time per fill

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Benchmarks

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

Boil-off rate, %/day

0.048 NASA KSC 2021, slide 10

0.1 Kawasaki catalogue product; DOE AMR 2022 ST241

0.19 DOE AMR 2022 ST235, slide 14

0.4 UC Davis ITS 2024, p. 9

CAPEX per kg of capacity, USD, USD/kg

30 UC Davis ITS 2024, p. 3

50 UC Davis ITS 2024, p. 3

Storage cost in US dollars, USD/kg

0.055 UC Davis ITS 2024, p. 3

0.091 UC Davis ITS 2024, p. 3

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.

42 outputs · 6 groups · 17 also shown above, dimmed

Storage cost

7
Storage cost per kg delivered
ComputingEUR/kg
Storage cost: capital
ComputingEUR/kg
Storage cost: O&M
ComputingEUR/kg
Storage cost: boil-off
ComputingEUR/kg
Boil-off share of storage cost
Computing%
Storage cost in US dollars
ComputingUSD/kg
Cost of one boiled-off kg
ComputingEUR/kg

Tank and CAPEX

6
Tank CAPEX (vessel, ex-works)
ComputingEUR
Specific CAPEX
ComputingEUR/m3
CAPEX scale exponent applied
Computingratio
CAPEX per kg of capacity
ComputingEUR/kg
CAPEX per kg of capacity, USD
ComputingUSD/kg
CAPEX per kg vs DOE 68 m3 vessel
Computingratio

Inventory

9
Stored LH2 mass
Computingt
Usable liquid volume
Computingm3
Ullage (vapour space)
Computing%
Margin to NASA minimum ullage
Computing%
LH2 delivered
Computingt/yr
Average send-out rate
Computingkg/h
Holding hours per turnover
Computingh
LH2 intake
Computingt/yr
LH2 intake per kg delivered
Computingkg/kg

Boil-off

9
Boil-off rate
Computing%/day
Boil-off losses
Computingkg/yr
Boil-off losses (t)
Computingt/yr
Daily boil-off
Computingkg/day
Boil-off per holding period
Computing%
Boil-off vs delivered
Computing%
Boil-off reused as gas
Computingt/yr
Reliquefaction electricity
ComputingMWh/yr
Reliquefaction electricity per kg delivered
ComputingkWh/kg

Checks against published tanks

4
Model boil-off at 60 m3
Computing%/day
Model vs UC Davis 60 m3 boil-off
Computingratio
Model boil-off at 11,200 m3
Computing%/day
Share of the Kawasaki 0.1 %/day ceiling
Computing%

Yearly costs

7
Capital recovery factor
Computing1/yr
Annualised CAPEX
ComputingEUR/yr
Fixed O&M
ComputingEUR/yr
Maintenance
ComputingEUR/yr
Insurance
ComputingEUR/yr
Boil-off cost
ComputingEUR/yr
Total yearly cost
ComputingEUR/yr

Sensitivities

5 charts
Storage cost components vs holding time

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Storage cost by boil-off management option

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Specific CAPEX and storage cost vs tank volume

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Boil-off rate vs tank volume

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Yearly boil-off by insulation reference case

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Sources

52 documented assumptions · 10 sources

About

Calculator context

Stationary vacuum-insulated tank holding liquid hydrogen at about 20 K, spherical or cylindrical, downstream of a liquefier. The calculator gives the storage cost per kg delivered in EUR/kg, split into capital, maintenance and insurance, and the cost of the boil-off; the stored mass; the boil-off rate at the chosen size and the yearly losses; the vessel CAPEX; and the liquid intake, reused gas and reliquefaction electricity that project mode chains. The size input is the geometric volume in m3, the capacity the catalogue binds on.

Inventory. Stored mass = geometric volume x fill ratio x 70.8 kg/m3 (Chart, DOE workshop 2022). The fill ratio goes up to 95 %, the maximum of the Linde tank specification in DOE ST235; NASA keeps a 10 % minimum ullage, and the page shows the margin against that rule.

Boil-off. Heat leaks in through the surface while the inventory grows with the volume, so the daily boil-off rate is scaled as volume^(-1/3) (NREL 1998) from one measured tank chosen as the reference case: the NASA LC-39 perlite spheres (3,218 m3, 0.0625 %/day), the new NASA glass-bubble sphere (4,732 m3, 0.048 %/day maximum) or the Linde 80 m3 station tank (0.19 %/day). Each case is a one-parameter calibration on one point, not a validation. Counter-checks with the NASA law: 0.21 %/day at 80 m3 against 0.19 printed by Linde, 0.041 %/day at 11,200 m3 against Kawasaki's guaranteed maximum of 0.1, but 0.24 %/day at 60 m3 against about 0.4 for the small older tanks UC Davis cites, while Gardner's 11-114 m3 station tanks print less than 0.2 %/day where the law gives 0.41 to 0.19. Small tanks therefore scatter by about a factor of 2 around the law in both directions. The yearly boil-off assumes the tank is kept full, the basis of the NASA rate, so it is an upper value for a tank that cycles.

Boil-off management. Vented or flared, each lost kg costs its gaseous value (4.90 EUR/kg, ACER, June 2025) plus the liquefaction already paid (1.14 EUR/kg, UC Davis $1.2/kg). Reused on site as gas, only the liquefaction is lost. Reliquefied, each kg costs 10 kWh of electricity (Argonne) at the Eurostat 2025 non-household price; the reliquefier CAPEX is not included, which favours this option.

CAPEX and storage cost. The vessel price is anchored on the DOE ST235 68 m3, 3,800 kg vessel at $620k (DFMA at 100 units a year, cross-checked by an INOXCVA quote of about $600k), converted at the 2022 ECB rate of 1.053 USD/EUR and scaled with NREL's sizing exponent of about 0.7. At 3,218 m3 the model gives about $43 per kg of capacity, inside the $30-50/kgH2 UC Davis range for large tanks; at 50,000 m3 about $19/kg, below it. Extrapolated to 100,000 m3 the law would give about $102 million against the DOE/Shell target of $175 million, so above about 10,000 m3 it is probably optimistic. The CAPEX is the ex-works vessel only: installation, foundations, transfer equipment, reliquefier, flare and land are left to project mode (battery_limit = exfactory). The storage cost annualises it at a 10 % real rate over 25 years, adds 1.5 % maintenance and 1.25 % insurance (Argonne) and the boil-off cost, and divides by the kg delivered, with the full inventory turned over once per holding period (7 days by default, the UC Davis one-week case). UC Davis gives $0.055-0.091/kg for one week in large tanks without O&M and without the value of the boil-off; this calculator counts both, so it sits above that range in vent mode.

Domain. The slider runs from 10 to 50,000 m3. Reference products cover 11 to 114 m3 (Gardner Cryogenics station tanks) and 2,500 to 11,200 m3 (Kawasaki Kobe and 11,200 m3 spheres, NASA spheres). Between about 114 and 2,500 m3 and above 11,200 m3 no product anchors the laws: the 50,000 m3 Kawasaki tank is a design, not a product, and the figures there are extrapolations.

Model

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

110 variables shown of 110
VariableValueUnitDepends on
3218m3—
7days—
1——
95%—
1——
0——
2700EUR/m3—
4.9EUR/kg—
1.14EUR/kg—
183.7EUR/MWh—
10%—
25years—
VariableFormulaUnitDepends on
if((<=)+(<=)+(>)+(<=)+(>)+(<)+(>)+(<)+(>)+(<)+(>)+(<=)+(<)+(<)+(<)+(<)+(>)+(<)>,,)bool
*ratio
*kg
if(==,,if(==,,))%/day
if(==,,if(==,,))m3
/max(,)ratio
*/kg/yr
if(==,,)bool
if(==,,)bool
if(==,,)bool
*kg/yr
*kg/yr
*kg/yr
++kg/yr
/EUR
/EUR/m3
/ratio
VariableFormulaUnitDepends on
**m3
-%
-%
/t
*^%/day
*(/max(,))^%/day
/ratio
*(/max(,))^%/day
/*%
*/h
**/%
**kg/day
*kg/yr
/t/yr
/t/yr
/kg/h
/max(,)*%
/t/yr
/t/yr
/max(,)kg/kg
**MWh/yr
*/max(,)kWh/kg
*(+)+*+***EUR/kg
*EUR/yr
if(>=,,clamp(*^(-),,))EUR/m3
if(>=,,)ratio
*EUR
/max(,)EUR/kg
*USD/kg
/(/)ratio
if(<,/,(*(+)^)/max((+)^-,))1/yr
*EUR/yr
**EUR/yr
**EUR/yr
+EUR/yr
++EUR/yr
/max(,)EUR/kg
/max(,)EUR/kg
/max(,)EUR/kg
++EUR/kg
*USD/kg
/max(,)*%

Assumptions

52 assumptions used in the calculations

  • Lower limit in the input guards and the zero branch of the mode switches.

    Market range Exact by definition.

    0
    Numerical constant

  • Unit multiplier in the CRF, the guards, the mode switches and the Customized switch.

    Market range Exact by definition.

    1
    Numerical constant

  • Converts a percent into a fraction.

    Market range Exact by definition.

    0.01
    Numerical constant

  • Converts a fraction into a percent; upper limit of a percent input.

    Market range Exact by definition.

    100
    Numerical constant

  • Kilograms per tonne.

    Market range Exact by definition.

    1000
    Numerical constant

  • Reference case 1: NASA LC-39 launch-pad sphere, evacuated perlite insulation.

    Market range Not applicable.

    1
    Selector code

  • Reference case 2: new NASA KSC sphere, glass-bubble insulation.

    Market range Not applicable.

    2
    Selector code

  • Reference case 3: Linde 80 m3 horizontal station tank of the DOE ST235 design basis.

    Market range Not applicable.

    3
    Selector code

  • Boil-off management 1: flare or vent, the boil-off is lost.

    Market range Not applicable.

    1
    Selector code

  • Boil-off management 2: the boil-off is used as gaseous hydrogen on site.

    Market range Not applicable.

    2
    Selector code

  • Boil-off management 3: the boil-off is reliquefied and returned to the tank.

    Market range Not applicable.

    3
    Selector code

  • Density of saturated liquid hydrogen near 1 bar, used for the stored mass. A pressurised tank stores slightly less per m3; the model keeps the 1-bar value.

    Market range About 70-71 kg/m3 at 1 bar; lower at higher saturation pressure.

    70.8kg/m3
    Chart / DOE workshop 2022

  • Upper limit of the fill ratio input: a liquid tank keeps at least 5 % of vapour space.

    Market range 95 % (Linde spec) to 90 % (NASA rule of a 10 % minimum ullage).

    95%
    DOE AMR 2022 ST235, slide 14

  • NASA's minimum vapour space for its large spheres; the model reports the margin of the chosen fill ratio against it, it does not enforce it.

    Market range 10 % (NASA) against 5 % (Linde station tank spec).

    10%
    NASA KSC 2021, slide 10

  • Anchor of reference case 1: measured normal evaporation rate of the 1960s LC-39 spheres, evacuated perlite insulation. One parameter fitted on one point: the size law around it is a calibration, not a validation.

    Market range 0.0625 (NASA slide) to about 0.07 %/day (UC Davis 2024) for the same tanks.

    0.0625%/day
    NASA KSC 2021, slide 5

  • Volume at which the case 1 boil-off rate is measured; the size law is pinned at this point.

    Market range Not applicable.

    3218m3
    NASA KSC 2021, slide 5

  • Anchor of reference case 2 (glass-bubble insulation) and a benchmark for the boil-off rate. It is a maximum specified for the new sphere.

    Market range 0.048 %/day maximum (specification).

    0.048%/day
    NASA KSC 2021, slide 10

  • Volume at which the case 2 boil-off rate is specified. NASA quotes it as usable capacity; the model applies it as geometric volume, a 10 % difference that moves the case 2 rate by about 3 %.

    Market range Not applicable.

    4732m3
    NASA KSC 2021, slide 10

  • Anchor of reference case 3 (station-size horizontal tank) and a benchmark for the boil-off rate.

    Market range Not applicable.

    0.19%/day
    DOE AMR 2022 ST235, slide 14

  • Volume at which the case 3 boil-off rate is given.

    Market range Not applicable.

    80.36m3
    DOE AMR 2022 ST235, slide 14

  • Boil-off rate is taken proportional to the surface-to-volume ratio, i.e. to volume^(-1/3) for tanks of the same shape and insulation. The exponent follows from geometry; the insulation quality is carried by the reference case.

    Market range Published small tanks scatter by a factor of about 2 around the law (see the counter-checks).

    -0.3333
    NREL 1998, geometric scaling

  • Size of the UC Davis small-tank example used for the model counter-check output.

    Market range Not applicable.

    60m3
    UC Davis ITS 2024, p. 9

  • Counter-check and benchmark: boil-off of a small tank of older design.

    Market range About 0.4 %/day (rounded, 'about').

    0.4%/day
    UC Davis ITS 2024, p. 9

  • Size of the Kawasaki sphere used for the model counter-check output.

    Market range Not applicable.

    11200m3
    Kawasaki catalogue product

  • Upper limit guaranteed by Kawasaki for its 11,200 m3 sphere; a benchmark ceiling, not a measured rate.

    Market range At most 0.1 %/day (guarantee).

    0.1%/day
    Kawasaki catalogue product; DOE AMR 2022 ST241

  • Purchase price of the reference vessel, ex-works: the vessel only, without installation, foundations, piping, vaporiser, reliquefier, flare or land. Hence battery_limit = exfactory in the meta.

    Market range $600k (INOXCVA) to $620k (DFMA).

    620000USD
    DOE AMR 2022 ST235, slides 15, 17

  • Size of the cost anchor; the scale law is pinned at this volume.

    Market range Not applicable.

    68m3
    DOE AMR 2022 ST235, slide 15

  • Hydrogen capacity of the cost anchor, used for the per-kg comparison output (reference price per kg of capacity).

    Market range Not applicable.

    3800kg
    DOE AMR 2022 ST235, slide 15

  • Economy of scale of the vessel cost with volume, applied from the 68 m3 anchor across the whole slider.

    Market range 0.7 'around' (NREL); no other exponent found for LH2 vessels.

    0.7
    NREL 1998, p. 20

  • Converts the 2022 US-dollar cost anchor into 2022 euros, and the model per-kg cost back into dollars for the UC Davis comparison.

    Market range Not applicable.

    1.053USD/EUR
    ECB 2022

  • Floor of the clamp on the specific CAPEX; it never binds inside the slider range (checked at 10 and 50,000 m3).

    Market range Not applicable.

    300EUR/m3
    Guard rail

  • Ceiling of the clamp on the specific CAPEX; it never binds inside the slider range.

    Market range Not applicable.

    40000EUR/m3
    Guard rail

  • Yearly maintenance as a share of the tank CAPEX. Argonne gives it for an LH2 carrier; transposed to a stationary tank, hence medium evidence.

    Market range No independent range cited.

    1.5%
    Argonne DOE AMR 2020 ST001, slide 10

  • Yearly insurance as a share of the tank CAPEX, same transposition as maintenance.

    Market range No independent range cited.

    1.25%
    Argonne DOE AMR 2020 ST001, slide 10

  • Electricity to reliquefy one kg of boil-off. Taken equal to the specific consumption of a large liquefier; a small reliquefier on a tank is probably less efficient, so this is a favourable value for the reliquefaction option.

    Market range 10 kWh/kg for large plants; small units are higher, no range cited.

    10kWh/kg
    Argonne DOE AMR 2020 ST001, slide 7

  • Low end of the UC Davis large-tank cost per kg of capacity, a benchmark for the model per-kg CAPEX. UC Davis dollars are 2024 dollars, the model dollars 2022 dollars: the comparison is about 5-8 % generous to the model.

    Market range $30-50/kgH2.

    30USD/kg
    UC Davis ITS 2024, p. 3

  • High end of the same range.

    Market range $30-50/kgH2.

    50USD/kg
    UC Davis ITS 2024, p. 3

  • Cross-check beyond the slider: the 0.7 law extrapolated to 100,000 m3 gives about $102 million, below this target, so the law is probably optimistic for the largest tanks. Not used in the calculation.

    Market range No independent range cited.

    175000000USD
    DOE AMR 2022 ST241, slide 2

  • Benchmark for the storage cost in dollars. UC Davis excludes O&M and the value of the boil-off, which this calculator counts, so the model is expected to sit above the range at large size in vent mode.

    Market range $0.055-0.091/kg for one week in large tanks.

    0.055USD/kg
    UC Davis ITS 2024, p. 3

  • High end of the same range.

    Market range $0.055-0.091/kg.

    0.091USD/kg
    UC Davis ITS 2024, p. 3

  • Source of the default liquefaction cost input: $1.2/kg at 1.053 USD/EUR gives 1.14 EUR/kg (dollar year of the report, 2024, converted at the 2022 rate; the gap is a few percent).

    Market range No independent range cited.

    1.2USD/kg
    UC Davis ITS 2024, p. 3

  • Default value of a kg of gaseous hydrogen, used to price vented boil-off and as the credit for reused gas. 2025 euros, not deflated to 2022.

    Market range 1.90 (SMR) to 8.00 EUR/kg (RFNBO) on the same date.

    4.9EUR/kg
    ACER CHEST, 30/06/2025

  • Default electricity price for the reliquefaction option. 2025 euros.

    Market range No independent range cited.

    183.7EUR/MWh
    Eurostat, H2 2025

  • Default cost of liquefying a kg upstream: lost with every vented kg, and the only loss when the boil-off is reused as gas.

    Market range No independent range cited.

    1.14EUR/kg
    UC Davis ITS 2024 p. 3, ECB 2022

  • Default holding time: the whole inventory turns over once a week, the UC Davis case.

    Market range 3 to 30 days on the slider.

    7days
    UC Davis ITS 2024, p. 3

  • Default discount rate of the capital recovery factor, applied as a real rate on constant-euro costs; no cost line is escalated.

    Market range No independent range cited.

    10%
    Argonne DOE AMR 2020 ST001, slide 10

  • Default economic and service life of the tank, also exported as the asset lifetime to project mode.

    Market range No independent range cited.

    25years
    Argonne DOE AMR 2020 ST001, slide 10

  • Method: inventory = geometric volume x fill ratio x 70.8 kg/m3; boil-off rate scaled as volume^(-1/3) from the reference case; vessel CAPEX scaled as volume^0.7 from the 68 m3 DOE anchor; storage cost = (annualised CAPEX + O&M + cost of the boil-off) / kg delivered, with one full inventory turnover per holding period.

    Market range Not applicable.

    —
    Model scope

  • The tank is assumed full all year, the basis on which NASA defines its evaporation rate. A tank cycled between full and empty boils off less in kg, so the yearly boil-off is a conservative upper value.

    Market range Not applicable.

    —
    Model scope

  • The CAPEX covers the vessel only. It excludes installation, foundations, transfer pumps, vaporiser, the reliquefier, the flare, a gas buffer and land. Project mode adds installation and indirect layers on top (battery_limit = exfactory).

    Market range Not applicable.

    —
    Model scope

  • Reference products cover 11 to 114 m3 and 2,500 to 11,200 m3. Between about 114 and 2,500 m3, and above 11,200 m3 (the 50,000 m3 Kawasaki tank is a design, not a product), the calculator extrapolates both laws.

    Market range Not applicable.

    —
    Model scope

  • The reliquefaction option counts electricity only; the reliquefier CAPEX and its maintenance are not included, which favours this option.

    Market range Not applicable.

    —
    Model scope