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Biogas CHP gas engine: efficiency by size, biogas flow, maintenance and LCOE with heat credit

Biogas CHP gas engine from 100 to 4,500 kW: electrical and thermal efficiency by size (ASUE 2011, DEA) or from Jenbacher J416/J620 datasheets, biogas flow in Nm3/h at the stated methane content, full-service maintenance per running hour (ASUE 2014), installed CAPEX with a sourced piecewise scaling law, and the LCOE with heat credit.

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Open Jack

Founder · OpenJack

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  • CurrencyEUR 2014
  • Battery limitinstalled
  • 89 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: 91.3 %

Hours a year the engine runs at rated output. Default 8,000 h (ENavi biogas reference plant). Flexible plants under the German EEG run about 3,942 h (BMWK 2024). Project mode sets it from the digester it is chained to.

Flows

  • In: Biogas (LHV)—

Asset

Biogas CHP gas engine

  • Out: Electricity—
  • Out: Heat sold (hot water)—

Annual quantities at the current usage.

Rated electrical output of the gas engine generator set. 100 to 4,500 kW. Default 1,248 kW, the INNIO Jenbacher J416 on biogas; the Jenbacher J620 is 3,349 kW. The cost laws (ASUE 2014) are fitted on offers up to about 2,500 kW and extrapolated above.

Biogas flow
— Nm3/h
Thermal output
— kW
Biogas energy input
— kW
Installed CAPEX
— EUR

CAPEX

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

Specific CAPEX at this size

—

Reference size 1,000 kW

ENavi 2021 / ASUE 2014

Model value: the ASUE 2014 module cost law for the size. Customized: your own module quote (ex-works, EUR per kW), used as is at every size; installation is still added from the ASUE bands, and the figure is then no longer sourced.

Specific module cost by electrical output

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

Included

  • Equipment
  • Installation, civil works and engineering

Not included

  • Working capital
  • Contingency

Added at project level

  • Working capital 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

Biogas (LHV) in
—
Electricity outMain product
—
Heat sold (hot water) out
—
CAPEX to the battery limit
—
Fixed O&M
—
Variable O&M, excluding feedstocks
—
Asset lifetime
25 years

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Levelised cost of electricity

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

—

  • Capital component—
  • Insurance and administration component—
  • Maintenance component—
  • Biogas component—
  • Heat credit—

Linked to the balance above

capacity factor: 91.3 %

Hours a year the engine runs at rated output. Default 8,000 h (ENavi biogas reference plant). Flexible plants under the German EEG run about 3,942 h (BMWK 2024). Project mode sets it from the digester it is chained to.

Volume share of methane in the raw biogas. FNR gives 50 to 75 %, and uses 55 % in its worked example. Sets the biogas flow in Nm3/h, the figure to compare with a digester's output.

Share of the co-produced heat sold to an outside user. Default 41.2 %, the mean external heat use of German biogas plants 2012-2017 (DBFZ Report 32); a further 26 % heats the digester itself.

Price of the heat sold, at the CHP flange. Default 30 EUR/MWh (3.0 ct/kWh_th, BMWK / Fraunhofer IEE / DBFZ 2024, 2023 data). Credited against the cost of electricity.

Cost of the biogas per MWh of lower heating value. Default 48.8 EUR/MWh: the IEA 2020 European average production cost of USD 16/MMBtu at the 2019 ECB rate. Use your own digestion cost (calculators #308 / #309) instead.

Feed-in tariff or sale price of the electricity, if you have one. 0 means none: the margin output then stays at 0. Only used for the margin against the LCOE.

Nominal weighted average cost of capital, as a fraction. Default 0.0734 (ENavi 2021). Costs are in constant euros, so the model converts it to a real rate with 2 % inflation (ECB target) before annualising the CAPEX.

Years over which the CAPEX is annualised. Default 20 years (BMWK / IEE / DBFZ 2024). DEA gives a technical lifetime of 25 years.

Levelised cost of electricity by running hours

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Benchmarks

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

Electrical efficiency, %

43 DEA Technology Data 06

43.7 Jenbacher J416 page

43.7 Jenbacher J620 page

Thermal efficiency, %

41.4 Jenbacher J620 page

48 ASUE 2011, Annex B

Maintenance per MWh, EUR/MWh

9.94 DEA Technology Data 06, derived

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.

59 outputs · 6 groups · 18 also shown above, dimmed

Cost of electricity

10
Levelised cost of electricity
ComputingEUR/MWh
Biogas component
ComputingEUR/MWh
Capital component
ComputingEUR/MWh
Maintenance component
ComputingEUR/MWh
Insurance and administration component
ComputingEUR/MWh
Heat credit
ComputingEUR/MWh
Cost of electricity before heat credit
ComputingEUR/MWh
Biogas share of the cost
Computing%
Margin against your tariff
ComputingEUR/MWh
IEA European biogas cost
ComputingEUR/MWh

Flows

11
Electricity generated
ComputingMWh/yr
Heat co-produced
ComputingMWh/yr
Heat sold
ComputingMWh/yr
Heat not sold
ComputingMWh/yr
Heat left after digester heating
ComputingMWh/yr
Heat sold above what is left
Computingbool
Biogas energy burnt
ComputingMWh/yr
Biogas flow
ComputingNm3/h
Methane flow
ComputingNm3/h
Biogas used a year
ComputingNm3/yr
Biogas heating value
ComputingkWh/Nm3

Performance

13
Electrical efficiency
Computing%
Thermal efficiency
Computing%
Total efficiency
Computing%
Size-law electrical efficiency
Computing%
Slope of the efficiency law
Computing%/ln
Specific biogas consumption
ComputingkWh/kWh
Biogas energy input
ComputingkW
Thermal output
ComputingkW
Power-to-heat ratio
Computingratio
Electrical output
ComputingMW
Conversion losses
ComputingMWh/yr
Heat and losses not sold
ComputingMWh/yr
Size far from the datasheet product
Computingbool

Operation

10
Running hours used
Computingh/yr
Capacity factor
Computing%
Fixed-cost factor against 8,000 h
Computingratio
Maintenance rate
Computingct/kWh
Maintenance per MWh
ComputingEUR/MWh
Maintenance per running hour
ComputingEUR/h
Maintenance a year
ComputingEUR/yr
Major overhaul cost (information)
ComputingEUR
Years to major overhaul (earliest)
Computingyears
Years to major overhaul (latest)
Computingyears

CAPEX

8
Installed CAPEX
ComputingEUR
Installed CAPEX per kW
ComputingEUR/kW
Module cost (ex-works)
ComputingEUR
Installation cost
ComputingEUR
Installation add-on
Computing%
Specific module cost
ComputingEUR/kW
Specific module cost at 1,000 kW
ComputingEUR/kW
Scale exponent applied
Computingratio

Annual costs

7
Capital recovery factor
Computing1/yr
Real discount rate
Computingratio
Annualised CAPEX
ComputingEUR/yr
Insurance and administration
ComputingEUR/yr
Biogas cost a year
ComputingEUR/yr
Heat revenue a year
ComputingEUR/yr
Net yearly cost
ComputingEUR/yr

Sensitivities

6 charts
Cost of electricity components vs running hours

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LCOE and installed CAPEX per kW vs engine size

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Electrical and thermal efficiency vs engine size

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Cost of electricity vs biogas cost

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Biogas flow vs methane content

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Maintenance per MWh and per running hour vs engine size

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Sources

89 documented assumptions · 11 sources

About

Calculator context

Unit calculator for a biogas combined heat and power (CHP) gas engine: a spark-ignition, lean-burn engine fed with raw digester biogas. Biogas comes in, electricity goes out, and the heat recovered from jacket water and exhaust is a co-product. The size input is the rated electrical output, 100 to 4,500 kW; the default 1,248 kW is the INNIO Jenbacher J416 on biogas.

Efficiencies. Three reference cases. (1) A size-based law: electrical efficiency rises log-linearly from 38 % at 100 kW (four ASUE 2011 biogas modules of 100-104 kW all print 38 %) to 43 % at 3 MW (Danish Energy Agency, biogas engine, 3-10 MWe), capped at 45 %; thermal efficiency is 86 % minus electrical (ASUE 100 kW modules and the J620 both print about 86 % total). This law is conservative against manufacturer top ratings: it gives 41.7 % at 1,248 kW where the J416 prints 43.3 % (up to 43.7 %), and 43.2 % at 3,349 kW where the J620 prints 43.7-44.8 %. (2) and (3): the printed biogas ratings of the Jenbacher J416 and J620, applied as is at the size set.

Biogas demand. Fuel input = electrical output / electrical efficiency; the biogas flow in Nm3/h divides it by 9.97 kWh/Nm3 of methane times the methane content (FNR, 50-75 %, default 55 %). This flow is the figure to compare with the digestion calculators #308 / #309.

Costs. The module cost follows the ASUE 2014 power law by size band (ENavi 2021, Table 1: exponent 0.675 from 100 to 1,000 kW, 0.883 above), plus an installation add-on of 51 % to 95 % of the module cost by band (ASUE 2014 via ENavi, Table 8). The sum is declared installed; planning, building, grid connection and gas treatment are excluded. Maintenance is a full-service contract including the major overhaul (ASUE 2014 via ENavi, Table 9), in ct/kWh: 18.3 EUR/MWh at 100 kW, 10.4 at 1,248 kW, 6.1 at 4,500 kW; it steps up at 1,000 kW where two regressions meet. Insurance and administration add 2.5 % of CAPEX a year. The LCOE annualises the CAPEX at a real rate (the ENavi 7.34 % nominal WACC deflated by the ECB 2 % target) over 20 years (BMWK 2024), adds maintenance, insurance and biogas (default 48.8 EUR/MWh, the IEA 2020 European average converted at the 2019 ECB rate), and credits the heat sold (41.2 % of the heat, DBFZ; 30 EUR/MWh, BMWK 2023).

Nominal case (1,248 kW, 8,000 h, 55 % CH4): 41.7 % electrical and 44.3 % thermal efficiency, 546 Nm3/h of biogas, 9,984 MWh of electricity and 10,601 MWh of heat a year, installed CAPEX 1.06 MEUR (847 EUR/kW), LCOE 125.5 EUR/MWh, of which biogas 117.0, maintenance 10.4, capital 8.7, insurance 2.6 and heat credit -13.1. Biogas makes 84 % of the cost before heat credit: the biogas cost input dominates the result.

Limits. Costs are in 2014 euros (ASUE) and are not escalated; BMWK 2024 reports biogas module costs up 26-44 % between 2020 and 2023, so use the Customized module cost for a current quote. Price years are mixed (2014 CAPEX and maintenance, 2019-2020 biogas, 2023 heat). The ASUE cost laws above 1,000 kW are fitted on offers plotted up to about 2,500 kW and are extrapolated to 4,500 kW. As a qualitative check only (different scope and year), the DEA gives 0.95 MEUR/MW for a 1-10 MWe biogas engine plant in 2020 euros. Part-load operation is not modelled.

Model

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

143 variables shown of 143
VariableValueUnitDepends on
1248kW—
1——
8000h/yr—
55%—
41.2%—
30EUR/MWh—
48.8EUR/MWh—
0EUR/MWh—
0.0734ratio—
20years—
0——
434EUR/kW—
VariableFormulaUnitDepends on
if((<=)+(>)+(<=)+(>)+(<)+(>)+(<)+(>)+(<)+(<)+(<)+(<)+(<=)+(<)+(>)+(<)+(>)+(<=)>0,1,0)bool
if(<,,if(<=,,))EUR/kW
if(<,,if(<=,,))ct/kWh
if(<,,if(<=,,))—
VariableFormulaUnitDepends on
*MW
min(,)h/yr
/*%
/max(,)ratio
(-)/ln(/)%/ln
min(+*ln(/),)%
if(==,,if(==,,))%
if(==,-,if(==,,))%
+%
/max(,)kWh/kWh
*kW
**kW
/max(,)ratio
**kWh/Nm3
/max(,)Nm3/h
**Nm3/h
*Nm3/yr
**MWh/yr
**MWh/yr
**MWh/yr
**MWh/yr
-MWh/yr
*(-)*MWh/yr
if(>-,,)bool
--MWh/yr
--MWh/yr
if(==,if(abs(/-)>*,,),if(==,if(abs(/-)>*,,),))bool
if(<,,if(<=,,))ratio
*^(-)EUR/kW
if(>=,,clamp(*(/)^(-),,))EUR/kW
*EUR
if(<,,if(<,,if(<,,if(<=,,))))%
**EUR
+EUR
/max(,)EUR/kW
(+)/(+*)-ratio
if(<,/max(,),(*(+)^)/max((+)^-,))1/yr
*EUR/yr
**EUR/yr
*^ct/kWh
*EUR/MWh
**EUR/h
*EUR/yr
*^*EUR
/max(,)years
/max(,)years
*EUR/yr
*EUR/yr
//EUR/MWh
+++-EUR/yr
/max(,)EUR/MWh
/max(,)EUR/MWh
/max(,)EUR/MWh
/max(,)EUR/MWh
-/max(,)EUR/MWh
+++EUR/MWh
+EUR/MWh
/max(,)*%
if(>,-,)EUR/MWh

Assumptions

89 assumptions used in the calculations

  • Protects divisions against a zero denominator.

    Market range Not applicable (numerical parameter).

    0
    Numerical guard.

  • Value of the flags when false, and lower limit of the validity checks.

    Market range Exact.

    0
    Unit conversion.

  • Unit value used in the CRF, the flags and the CAPEX basis switch.

    Market range Exact.

    1
    Unit conversion.

  • Percent scale.

    Market range Exact.

    100
    Unit conversion.

  • Turns a percent into a fraction.

    Market range Exact.

    0.01
    Unit conversion.

  • Hours in a year; upper limit of the running hours.

    Market range Exact.

    8760h/yr
    Unit conversion.

  • kW x h to MWh.

    Market range Exact.

    0.001MWh/kWh
    Unit conversion.

  • kW to MW.

    Market range Exact.

    0.001MW/kW
    Unit conversion.

  • Euro cents to euros.

    Market range Exact.

    0.01EUR/ct
    Unit conversion.

  • 1 ct/kWh = 10 EUR/MWh.

    Market range Exact.

    10(EUR/MWh)/(ct/kWh)
    Unit conversion.

  • 1 MMBtu (million British thermal units) = 0.29307107 MWh; used to convert the IEA biogas cost.

    Market range Exact.

    0.293071MWh/MMBtu
    Unit conversion.

  • Small-size anchor of the electrical efficiency law (model case).

    Market range 38 % on all four 100-104 kW modules listed.

    38%
    ASUE 2011, Annex B

  • Electrical power of the small anchor.

    100kW
    ASUE 2011, Annex B

  • Large-size anchor of the electrical efficiency law (model case).

    Market range DEA 43 % (net, 3-10 MWe) to 44.8 % (Jenbacher J620 datasheet).

    43%
    DEA Technology Data 06

  • Electrical power of the large anchor.

    3000kW
    DEA Technology Data 06, note A

  • Ceiling on the size-based electrical efficiency.

    Market range Not reached in 100-4,500 kW.

    45%
    Jenbacher J620 page

  • Total (electrical + thermal) efficiency of the model case; thermal = total - electrical.

    Market range 86 % (ASUE, J620) to 88.4 % (J620 second rating).

    86%
    ASUE 2011 + Jenbacher J620

  • Reference case 1: size-based efficiency law (ASUE 2011 / DEA).

    Market range Not applicable.

    1
    Selector.

  • Reference case 2: INNIO Jenbacher J416 biogas datasheet.

    Market range Not applicable.

    2
    Selector.

  • Reference case 3: INNIO Jenbacher J620 biogas datasheet.

    Market range Not applicable.

    3
    Selector.

  • Lowest valid reference case.

    Market range Not applicable.

    1
    Selector.

  • Highest valid reference case.

    Market range Not applicable.

    3
    Selector.

  • Electrical efficiency of case 2.

    Market range 43.3 % (biogas rating) to 43.7 % (type maximum).

    43.3%
    Jenbacher J416 page

  • Thermal efficiency of case 2.

    Market range No independent range cited.

    43.4%
    Jenbacher J416 page

  • Rated electrical output of the J416.

    Market range Not applicable.

    1248kW
    Jenbacher J416 page

  • Electrical efficiency of case 3.

    44.8%
    Jenbacher J620 page

  • Thermal efficiency of case 3.

    41.4%
    Jenbacher J620 page

  • Rated electrical output of the J620.

    Market range Not applicable.

    3349kW
    Jenbacher J620 page

  • Tolerance of the size-mismatch flag of cases 2 and 3.

    Market range Not applicable.

    50%
    Model convention.

  • Energy of one Nm3 of methane (LHV).

    Market range 9.97 kWh/Nm3 (LHV).

    9.97kWh/Nm3
    FNR 2008

  • Lowest valid methane content.

    50%
    FNR 2008

  • Highest valid methane content.

    75%
    FNR 2008

  • Upper limit of the validity domain of the size input.

    Market range Not applicable.

    8924kW
    ASUE 2011

  • Lower band edge of the cost laws.

    Market range Not applicable.

    100kW
    ENavi 2021, Table 1

  • Upper band edge of the cost laws.

    Market range Not applicable.

    1000kW
    ENavi 2021, Table 1

  • Reference size at which the specific module cost is anchored.

    Market range Not applicable.

    1000kW
    ENavi 2021, Table 1

  • Coefficient of the module cost law below 100 kW.

    Market range No independent range cited.

    10267EUR/kW
    ENavi 2021 / ASUE 2014

  • Scale exponent of the module cost below 100 kW.

    Market range No independent range cited.

    0.503
    ENavi 2021 / ASUE 2014

  • Coefficient of the module cost law from 100 to 1,000 kW.

    Market range ASUE 2011: 15648 x P^-0.536 EUR/kW (2011 basis).

    4276EUR/kW
    ENavi 2021 / ASUE 2014

  • Scale exponent of the module cost from 100 to 1,000 kW, the declared law of the page; above 1,000 kW the flatter ASUE band takes over.

    Market range 0.464 (ASUE 2011) to 0.883 (ASUE 2014 above 1 MW).

    0.675
    ENavi 2021 / ASUE 2014

  • Coefficient of the module cost law above 1,000 kW.

    Market range No independent range cited.

    1,000.1EUR/kW
    ENavi 2021 / ASUE 2014

  • Scale exponent of the module cost above 1,000 kW.

    Market range No independent range cited.

    0.883
    ENavi 2021 / ASUE 2014

  • Lower guard of the specific module cost.

    Market range Not applicable (numerical parameter).

    100EUR/kW
    Numerical guard.

  • Upper guard of the specific module cost.

    Market range Not applicable (numerical parameter).

    20000EUR/kW
    Numerical guard.

  • Band edge of the installation add-on.

    Market range Not applicable.

    350kW
    ENavi 2021, Table 8

  • Band edge of the installation add-on.

    Market range Not applicable.

    500kW
    ENavi 2021, Table 8

  • Band edge of the installation add-on.

    Market range Not applicable.

    750kW
    ENavi 2021, Table 8

  • Installation add-on on the module cost: transport, assembly, connection and integration (planning, building, grid connection and gas treatment excluded).

    Market range 51 % (<350 kW) to 95 % (>1,000 kW) across the ASUE bands.

    51%
    ENavi 2021, Table 8

  • Installation add-on on the module cost: transport, assembly, connection and integration (planning, building, grid connection and gas treatment excluded).

    Market range 51 % (<350 kW) to 95 % (>1,000 kW) across the ASUE bands.

    60%
    ENavi 2021, Table 8

  • Installation add-on on the module cost: transport, assembly, connection and integration (planning, building, grid connection and gas treatment excluded).

    Market range 51 % (<350 kW) to 95 % (>1,000 kW) across the ASUE bands.

    66%
    ENavi 2021, Table 8

  • Installation add-on on the module cost: transport, assembly, connection and integration (planning, building, grid connection and gas treatment excluded).

    Market range 51 % (<350 kW) to 95 % (>1,000 kW) across the ASUE bands.

    74%
    ENavi 2021, Table 8

  • Installation add-on on the module cost: transport, assembly, connection and integration (planning, building, grid connection and gas treatment excluded).

    Market range 51 % (<350 kW) to 95 % (>1,000 kW) across the ASUE bands.

    95%
    ENavi 2021, Table 8

  • Coefficient of the full-service maintenance law.

    Market range ASUE 2011: 17.053 x P^-0.478 ct/kWh_el.

    16.1ct/kWh
    ENavi 2021 / ASUE 2014

  • Coefficient of the full-service maintenance law.

    Market range ASUE 2011: 17.053 x P^-0.478 ct/kWh_el.

    6.869ct/kWh
    ENavi 2021 / ASUE 2014

  • Coefficient of the full-service maintenance law.

    Market range ASUE 2011: 17.053 x P^-0.478 ct/kWh_el.

    19.396ct/kWh
    ENavi 2021 / ASUE 2014

  • Exponent of the full-service maintenance law.

    Market range No independent range cited.

    -0.431
    ENavi 2021 / ASUE 2014

  • Exponent of the full-service maintenance law.

    Market range No independent range cited.

    -0.287
    ENavi 2021 / ASUE 2014

  • Exponent of the full-service maintenance law.

    Market range No independent range cited.

    -0.411
    ENavi 2021 / ASUE 2014

  • Coefficient of the major overhaul cost.

    Market range No independent range cited.

    830.23EUR/kW
    ASUE 2011

  • Exponent of the major overhaul cost.

    Market range No independent range cited.

    -0.268
    ASUE 2011

  • Shortest interval to the major overhaul.

    30000h
    ENavi 2021

  • Longest interval to the major overhaul.

    60000h
    ENavi 2021

  • Yearly insurance and administration as a share of CAPEX.

    Market range No independent range cited.

    2.5%
    ENavi 2021, Annex A

  • Inflation used in the Fisher conversion of the nominal discount rate.

    Market range 2 % (target).

    2%
    ECB strategy

  • Reference running hours; default of the usage lever and basis of the fixed-cost factor.

    Market range 3,942 h (BMWK flexible) to 8,000 h (ENavi baseload).

    8000h/yr
    ENavi 2021, Table 5

  • European average biogas production cost, the basis of the default biogas price.

    Market range USD 2-20/MMBtu globally.

    16USD/MMBtu
    IEA 2020

  • Exchange rate for the IEA biogas cost conversion.

    Market range Not applicable.

    1.1195USD/EUR
    ECB 2019

  • Share of the CHP heat used by the digester itself; caps the heat that can be sold.

    Market range No independent range cited.

    26%
    DBFZ Report 32

  • Printed thermal efficiency of 100 kW biogas modules, a reference for the thermal efficiency output.

    48%
    ASUE 2011, Annex B

  • Top printed electrical efficiency of the J416, a reference for the electrical efficiency output.

    43.7%
    Jenbacher J416 page

  • Reference for the electrical efficiency output.

    43.7%
    Jenbacher J620 page

  • DEA O&M per MWh for a 1-10 MWe biogas engine, a reference for the maintenance output.

    Market range No independent range cited.

    9.94EUR/MWh
    DEA Technology Data 06, derived

  • Cross-check of the installed CAPEX per kW.

    Market range No independent range cited.

    950EUR/kW
    DEA Technology Data 06

  • DEA variable O&M.

    Market range No independent range cited.

    7.5EUR/MWh
    DEA Technology Data 06

  • DEA fixed O&M.

    Market range No independent range cited.

    9750EUR/MW/yr
    DEA Technology Data 06

  • Physical service life of the engine plant, with major overhauls inside the maintenance contract.

    Market range No independent range cited.

    25years
    DEA Technology Data 06

  • Default of the economic lifetime input.

    Market range 20 (BMWK) to 25 years (DEA technical).

    20years
    BMWK 2024

  • Default of the discount rate input.

    Market range No independent range cited.

    0.0734ratio
    ENavi 2021, Table 2

  • Default heat price.

    Market range No independent range cited.

    30EUR/MWh
    BMWK 2024

  • Default share of heat sold.

    Market range No independent range cited.

    41.2%
    DBFZ Report 32

  • Default biogas cost; replace with your own digestion cost.

    Market range USD 2-20/MMBtu globally (IEA).

    48.8EUR/MWh
    IEA 2020 + ECB 2019, derived

  • Default methane content.

    55%
    FNR 2008

  • Recent module cost escalation, stated so that the 2014 basis is not mistaken for a current price.

    Market range +26 % to +44 % (2020 to 2023).

    37%
    BMWK 2024

  • Scope: one spark-ignition lean-burn gas engine CHP module running on raw digester biogas. Biogas in (LHV basis), electricity out at the generator terminals, heat co-produced from jacket water and exhaust. Gas treatment (desulphurisation, drying), the digester, buildings, planning and grid connection are outside the CAPEX. The engine runs at rated output during its running hours: part-load operation is not modelled.

    Market range Not applicable.

    —
    Model scope.

  • Electrical efficiency of the size-based case: a log-linear interpolation, 38 % at 100 kW (ASUE) to 43 % at 3 MW (DEA), slope (43 - 38)/ln(30) = 1.47 points per ln unit, capped at 45 %. It is a two-anchor model, not a regression. Against independent datasheets it is conservative: 41.7 % at 1,248 kW where the J416 prints 43.3 % (up to 43.7 %), and 43.2 % at 3,349 kW where the J620 prints 43.7-44.8 %; DEA note A puts a 1 MWe engine at about 38-39 %. Thermal efficiency is 86 % minus electrical (ASUE 100 kW modules and J620 both print about 86 % total).

    Market range Not applicable.

    —
    Efficiency model.

  • CAPEX = module cost (ASUE 2014 power law, piecewise by size band: module, controls, remote monitoring, lube oil system, catalyst, silencer, ventilation) plus the ASUE installation add-on (transport to acceptance plus connection and integration, 51 % to 95 % of the module cost by band). The module price alone is an ex-works figure and is shown separately; only the sum is declared installed (battery_limit installed). Planning, building, grid connection and gas treatment are excluded, so project mode, which adds its working layer and contingency on an installed figure, still lacks them. Costs are ASUE 2014 euros, not escalated: BMWK 2024 reports module costs up 26-44 % between 2020 and 2023.

    Market range Not applicable.

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    CAPEX boundary.

  • Maintenance is a full-service contract price per kWh of electricity, including the major overhaul (due after 30,000-60,000 running hours). The overhaul cost (ASUE 2011, 830.23 x P^-0.268 EUR/kW) is shown for information only and never added. The ASUE law steps up at 1,000 kW (0.95 to 1.13 ct/kWh) because two separate regressions meet there. Insurance and administration add 2.5 % of CAPEX a year (ENavi Annex A).

    Market range Not applicable.

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    Maintenance model.

  • All costs are constant euros (ASUE 2014, IEA 2020, BMWK 2023 bases, none escalated), so the CAPEX is annualised at a real rate: (1 + nominal WACC)/(1 + 2 %) - 1, i.e. 5.24 % real for the 7.34 % ENavi default. Below 2 % nominal the real rate would turn negative; the CRF then falls back to 1/lifetime. The price years are mixed (2014 CAPEX and maintenance, 2019-2020 biogas, 2023 heat): the LCOE is an order of magnitude to defend, not a dated price.

    Market range Not applicable.

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    Finance convention.

  • Upstream chaining: the biogas flow in Nm3/h at the stated methane content is the figure to compare with a digester's output (#308 / #309). Project mode prices the biogas inlet on its LHV energy (MWh a year); the biogas cost input is only used by this calculator's own LCOE. The heat credit is internal to the LCOE: project mode sells the heat outlet itself, so do not add both.

    Market range Not applicable.

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    Chaining rule.