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Concentrating solar process steam

Linear Fresnel solar field delivering 150-390 C industrial process steam: annual yield, steam tonnage, solar fraction and LCOH in EUR/MWh_th, with no power block.

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Open Jack

Founder · OpenJack

Cost of heat

Installed cost of the collector field per m2 of aperture, excluding BOP, land and steam distribution. 240 is a documented real plant, 304 a large commercial field, 450 a small rooftop field. This is where economies of scale live - no scaling exponent is applied on top. The 240 EUR/m2 floor follows the 241.8 EUR/m2 case figure of the cited Fresnel cost study; that figure is read from the study and has not been re-derived here.

Field maintenance and operation only (mirror washing, tracking, controls, inspection). Make-up feed and auxiliary power are declared as project inlets and are NOT counted here.

Real discount rate used to annualize the CAPEX through the capital recovery factor.

Economic lifetime of the field. The manufacturer quotes a technical life above 20 years; the reference study levelizes over 25.

years

Levelized cost of heat (LCOH)

Headline number: annualized CAPEX plus field O&M divided by the heat actually delivered

…EUR/MWh_th

Levelized cost per tonne of steam

The same annual cost divided by tonnes instead of MWh_th

…EUR/t

Position in the SHIP cost band

Where this LCOH lands between the 30 and 70 EUR/MWh_th of built SHIP plants

…%

Installed solar field CAPEX

Collector field installed, excluding BOP, land and steam distribution

…EUR

Annualized CAPEX

CAPEX spread over the lifetime through the capital recovery factor

…EUR/year

Annual field O&M cost

Mirror washing, tracking maintenance, controls and inspection

…EUR/year

Total annual cost of the solar field

Annualized CAPEX plus field O&M; the numerator of the LCOH

…EUR/year

CAPEX share of the annual cost

How capital-dominated this heat is

…%

Specific CAPEX per kW of thermal capacity

Field cost per kW_th of nominal capacity, for comparison with boiler and CSP quotes

…EUR/kW_th
Sensitivity to installed field cost

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Sensitivity to the discount rate

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Solar resource and field performance

Site DNI. Concentrating collectors only see the direct beam. Below about 1900 kWh/m2/yr a linear Fresnel field stops competing with a gas boiler - a rule of thumb from the Fresnel cost literature, not a figure verified against a primary source here.

Optical efficiency at normal incidence (mirror reflectivity x absorptance x intercept factor). 0.635 is the LF-11 datasheet value, confirmed at 0.632 by Famiglietti & Abbas.

Aggregate annual derate: cosine and incidence-angle losses, end losses, row shading, start-up and shutdown, piping losses. Back-solved from the annual yield published by Famiglietti & Abbas for southern Spain.

Quadratic loss coefficient u1 per m2 of PRIMARY aperture, as published for the evacuated receiver (0.00043 W/m2/K2 according to DLR). Wind independent because the absorber is under vacuum.

W/m2/K2

Annual mean ambient temperature at the site; it is the cold end of the receiver loss term. 19.2 C is the AEMET normal for Seville.

Solar field thermal efficiency

Useful heat delivered per unit of DNI falling on the aperture, over a full year

…%

Specific yield per m2 of aperture

Annual useful heat per m2, the number solar thermal fleets are benchmarked on

…kWh/m2/year

Specific yield vs SHIP fleet benchmark

Where this field sits against the 550 kWh/m2/yr the IEA SHC quotes for built plants

…%

Annual optical gain

Energy the mirrors put on the receiver before any thermal loss

…kWh/m2/year

Annual receiver heat loss

Thermal loss of the absorber over the operating hours, per m2 of primary aperture

…kWh/m2/year

Receiver loss penalty on the optical gain

Share of the collected optical energy lost again in the receiver

…ratio

Annual field operating hours

Hours the field is on sun; the receiver loses heat for exactly this long

…h/year

Recomputed datasheet reference output

The model evaluated at the manufacturer reference conditions

…W/m2

Deviation from the datasheet reference point

How far the entered collector sits from the published LF-11 performance

…%
Sensitivity to site DNI

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Steam delivered

Delivery pressure at the field outlet. It sets the saturation temperature, which drives the receiver losses. 40 bar is the standard rating of the collector loop.

Degrees of superheat above saturation. Superheat raises both the delivered enthalpy per tonne and the mean field temperature, so it costs twice.

Temperature of the water entering the solar steam generator, typically returned condensate. Hotter feedwater means less energy per tonne of steam.

Annual steam demand of the host process. It sets the solar fraction only - it never changes the cost of the heat the field produces.

t/year

Annual steam production

Main product, and the denominator of the project-mode levelized cost

…t/year

Annual useful heat delivered

Thermal energy leaving the solar field, before any distribution loss

…MWh_th/year

Solar fraction of the site steam demand

Share of the host process steam demand covered by the field, capped at full coverage

…%

Thermal energy needed per tonne of steam

Enthalpy rise from feedwater to delivered steam, in thermal kWh per tonne

…kWh_th/t

Saturation temperature at delivery pressure

What the field has to run at, which is what the receiver loses heat against

…°C

Delivered steam temperature

Saturation temperature plus the requested superheat

…°C

Annual feedwater requirement

Exact mass balance with the steam leaving the field

…t/year
Cost of delivering steam at higher pressure

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Cost of superheat

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Solar fraction vs host steam demand

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Field sizing and site footprint

Primary reflector aperture of the collector field. Costs and output both scale linearly with it, so the levelized cost is flat in field size - the cost per m2 input is where scale shows up.

Tracking drives and controls, per m2 of aperture (1.70 W/m2 from the LF-11 electrical peak consumption). Feedwater pumping is outside the field boundary. This is the adjustable upstream knob of the electricity inlet in project mode.

W/m2

Nominal thermal capacity of the field

Peak thermal output at the manufacturer reference conditions

…MW_th

Collector modules required

Aperture rounded up to whole LF-11 basic modules

…modules

Ground area required

Aperture times the row-spacing land use factor

…m2

Annual auxiliary electricity

Tracking drives and controls over the operating hours

…MWh/year
Effect of field size (LCOH is flat by construction)

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About

Calculator context

Sizes and costs a concentrating solar field - linear Fresnel or small parabolic trough - that delivers saturated or lightly superheated process steam between 150 and 390 C directly to an industrial site. There is no power block: the product is heat, so the answer is an LCOH in EUR/MWh_th and a tonnage of steam, never an LCOE.

The core is the published collector characteristic curve, q_u = DNI x eta_0 x IAM - u1 x (T_mean - T_ambient)^2, taken per m2 of primary aperture. At the manufacturer's reference conditions (900 W/m2 DNI, 160/180 C, 30 C ambient) the model returns 561.93 W/m2 against a published 562 W/m2, a 0.01 % deviation - and that check is exposed as an output, so a user who changes the optics can see how far from a real commercial collector they have moved.

Going annual splits the balance in two terms that do not scale together: the optical gain follows the annual DNI, while the receiver loss follows the HOURS the field runs. Operating hours therefore come from the annual DNI divided by a mean operating irradiance of 720 W/m2, itself derived from 2100 kWh/m2/yr over 2917 sunshine hours. Saturation temperature is inverted from the delivery pressure with the NIST Antoine set (deviation -3.5 K to +3.4 K over 6-40 bar, worth under 0.2 % on the LCOH because it only feeds the loss term), and the enthalpy rise per tonne of steam reproduces DOE Steam Tip Sheet #15 Table 1 to within 0.07-0.95 %.

At the nominal case - 5000 m2 of aperture, DNI 1900 kWh/m2/yr, 16 bar saturated steam, 90 C feedwater, 304 EUR/m2 installed, 5 % real over 25 years - the field yields 605 kWh/m2/yr, 31.9 % annual thermal efficiency on DNI, 3027 MWh_th and 4535 t of steam per year, at 45.7 EUR/MWh_th. That sits in the middle of the 30-70 EUR/MWh_th band the IEA SHC reports for built SHIP plants.

Two modelling choices are deliberate and visible. The CAPEX is strictly linear in aperture - no scaling exponent, no clamp - so the LCOH curve against field size is FLAT: the six-tenths rule applies to a total cost, not to a cost per m2, and a clamp that can bite between the slider bounds would freeze the cost model inside its own declared domain. Economies of scale live in the 240-450 EUR/m2 input range instead. And the specific yield is a SIGNED quantity: ask for 390 C on a 1600 kWh/m2/yr site with a poor receiver and the field delivers nothing, so the guard refuses the case rather than returning a large finite number.

Excluded, and to be added at project level: thermal storage, fossil back-up, feedwater pumping and treatment, steam distribution, and land cost. Feedwater and auxiliary electricity are declared as project inlets so the project prices them - they are never booked in the field O&M as well.

Model

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

116 variables shown of 116
VariableValueUnitDepends on
5000m2—
1900kWh/m2/year—
0.635ratio—
0.58ratio—
0.00043W/m2/K2—
16bar—
0K—
90°C—
20°C—
304EUR/m2—
2%—
0.05ratio—
25years—
15000t/year—
1.7W/m2—
VariableFormulaUnitDepends on
if((<=)+(<=)+(<=)+(>)+(<=)+(>)+(<)+(<=)+(>)+(<)+(<)+(<=)+(<)+(<)+(<=)+(<=)+(<)+(((/max(-log(max(,))/,)--)+)>)+(>=(/max(-log(max(,))/,)--))+((+*-*)<=)+(((****)-(*(((/max(-log(max(,))/,)--)+*)-)^*(*/max(,))/))<=)>,,)bool
+*°C
-K
*^W/m2
+*-*kJ/kg
*EUR/m2
if(<,/max(,),(*(+)^)/max((+)^-,))ratio
VariableFormulaUnitDepends on
/max(-log(max(,))/,)--°C
+°C
*/max(,)h/year
****kWh/m2/year
*/kWh/m2/year
/max(,)ratio
-kWh/m2/year
*/max(,)%
*/max(,)%
*/MWh_th/year
/max(,)kWh_th/t
*/max(,)t/year
*t/year
*/*/MWh/year
*min(,)/max(,)%
**-*(*(+)-)^W/m2
*(-)/max(,)%
*//MW_th
ceil(/max(,))modules
*m2
*EUR
/max(*,)EUR/kW_th
*EUR/year
**EUR/year
+EUR/year
*/max(,)%
/max(,)EUR/MWh_th
/max(,)EUR/t
*(-)/max(-,)%

Assumptions

65 assumptions used in the calculations

  • Guards divisions and sign tests; small enough never to move a physical result.

    Market range Not applicable (numerical parameter).

    0
    Numerical guard convention for DSL calculators.

  • Named zero so no bare literal appears in a domain guard.

    Market range Exact.

    0
    Numerical convention.

  • CHAINING RULE for project mode. The feedwater inlet is linked to the steam produced with a coefficient of exactly 1: the field exports every tonne it takes in, so any upstream link (water treatment, condensate return, borehole) must keep coefficient 1 - a partial coefficient would silently destroy mass at the netting step. The legitimate upstream of the electricity inlet is any generator or grid supply, also at coefficient 1; the adjustable knob on that link is the parasitic power input, not the link itself. Neither inlet shares a commodity with the steam outlet, so no same-commodity conversion rule is needed.

    Market range Exact (1 t/t).

    1
    Mass balance of a once-through solar steam generator (1 t of feedwater per 1 t of steam) and the CRF zero-rate branch.

  • Evaporation happens at saturation temperature; only the superheater section rises above it, so the field mean temperature sits at T_sat + half of the superheat. Applying the full superheat would overstate the receiver loss term.

    Market range 0.5 for a once-through evaporator + superheater train.

    0.5
    Mean-temperature convention for a once-through solar steam generator.

  • Converts a ratio into a percentage for display outputs.

    Market range Exact.

    100%
    Percent convention.

  • Reconverts the O&M percentage input into a fraction inside the DSL.

    Market range Exact.

    0.01
    Percent convention (OpenJack: percent inputs are 0-100).

  • Converts MWh to kWh and back.

    Market range Exact.

    1000kWh/MWh
    SI unit conversion.

  • Converts W/m2 loss rates and kWh/m2 irradiation into a common basis (also gives operating hours from annual DNI divided by a mean operating irradiance).

    Market range Exact.

    1000W/kW
    SI unit conversion.

  • Converts the nominal thermal capacity from MW to kW for the specific CAPEX output.

    Market range Exact.

    1000kW/MW
    SI unit conversion.

  • Antoine returns a temperature in kelvin; the calculator reports Celsius.

    Market range Exact.

    273.15K
    SI definition of the Celsius scale.

  • The DSL exposes a natural logarithm only, so log10(P) is evaluated as ln(P)/ln(10).

    Market range Exact.

    2.302585
    Mathematical constant ln(10).

  • Turns the specific enthalpy rise (kJ/kg) into the thermal energy needed per tonne of steam (kWh_th/t).

    Market range Exact.

    3.6kJ.t/(kg.kWh)
    SI unit conversion (1 kJ/kg = 1/3.6 kWh/t).

  • The published loss term of the evacuated-receiver Fresnel collector is quadratic in the temperature lift, with no linear term - which is why it is wind independent.

    Market range 2 (quadratic) for vacuum absorbers; flat-plate collectors need a linear term as well.

    2
    Industrial Solar GmbH, Technical Data LF-11 - collector characteristic curve q_u = DNI x eta_0 x IAM - u1 x (T_m - T_amb)^2.

  • Reference peak optical efficiency of a commercial linear Fresnel collector; the default of the matching input.

    0.635ratio
    Industrial Solar GmbH, Technical Data - linear Fresnel collector LF-11 (eta_0 = 0.635 for sun in zenith, eta_max = 0.663 at 5 deg transversal).

  • The optical efficiency peaks slightly off zenith (5 deg transversal); grounds the upper part of the optical efficiency input range.

    Market range 0.663 at the transversal optimum.

    0.663ratio
    Industrial Solar GmbH, Technical Data LF-11 - optical performance characteristics.

  • Independent confirmation of the LF-11 datasheet value (0.635) by a peer-reviewed techno-economic study, which is why the nominal is not treated as a single-vendor number.

    0.632ratio
    Famiglietti A., Abbas R., Solar 2025, 5, 27, Table 3 - maximum optical efficiency eta_op0 = 0.632 for a commercial LFC.

  • Reference receiver loss coefficient per m2 of PRIMARY aperture (not per m2 of absorber); the default of the matching input.

    0.00043W/m2/K2
    Industrial Solar GmbH, Technical Data LF-11 - 'Thermal loss per m2 of primary reflector: u1 = 0.00043 W/(m2K2) (according to DLR)', vacuum absorber so the loss is wind independent.

  • Documents what the peak optical efficiency is made of (reflectivity x absorptance x intercept); not re-applied on top of eta_0, which would double count it.

    0.95ratio
    Industrial Solar GmbH, Technical Data LF-11 - 'Mirror reflectivity 95%'; Schott PTR70 receiver: solar absorptance 95%, thermal emittance 9% at 380 C.

  • Annual average soiling derate applied on top of the peak optical efficiency.

    0.95ratio
    Famiglietti & Abbas, Solar 2025, 5, 27, Table 3 - mirrors cleanliness eta_clean = 0.95.

  • Fraction of the year the field is available (planned and unplanned outages excluded).

    0.965ratio
    Famiglietti & Abbas, Solar 2025, 5, 27, Table 3 - solar field availability eta_av = 0.965.

  • Aggregate annual factor: cosine losses, transversal and longitudinal IAM, end losses, row shading and blocking, start-up and shutdown, piping and BOP heat losses. It is an assumed aggregate, not a pure IAM - the nominal 0.58 is back-solved from a published annual yield, not measured.

    0.58ratio
    DERIVED from Famiglietti & Abbas, Solar 2025, 5, 27, Section 3.1 - 'CST gives the highest E_A,gr production above 0.5 MWh m-2 in southern Spain' (per ground area) with land use factor F_land = 1.3, i.e. 650 kWh/m2 of aperture; solving the annual balance at T_m = 170 C gives K = 0.584 (DNI 2000) to 0.558 (DNI 2100).

  • Model validation point: this calculator reproduces it at 561.93 W/m2, a 0.01 % deviation, which is what the datasheet-deviation output reports.

    Market range 562 W/m2 at the datasheet reference conditions.

    562W/m2
    Industrial Solar GmbH, Technical Data LF-11 - 12.3 kW per standard module, 562 W/m2 of aperture, 377 W/m2 of installation area.

  • Irradiance of the manufacturer reference point used by the datasheet check.

    Market range 900 W/m2 (datasheet convention).

    900W/m2
    Industrial Solar GmbH, Technical Data LF-11 - reference conditions: 30 C ambient, 900 W/m2 DNI, 160 C inflow, 180 C outflow, azimuth 90 deg, zenith 30 deg.

  • Incidence angle modifier at the datasheet reference point; without it the recomputed reference output lands at 563.1 W/m2 instead of 561.9 W/m2.

    0.998ratio
    Industrial Solar GmbH, Technical Data LF-11 - transversal IAM at the reference zenith angle of 30 deg (longitudinal IAM = 1 at the reference azimuth).

  • Inflow temperature of the manufacturer reference point.

    Market range 160 C (datasheet convention).

    160°C
    Industrial Solar GmbH, Technical Data LF-11 - reference conditions.

  • Outflow temperature of the manufacturer reference point (mean field temperature 170 C).

    Market range 180 C (datasheet convention).

    180°C
    Industrial Solar GmbH, Technical Data LF-11 - reference conditions.

  • Ambient temperature of the manufacturer reference point.

    Market range 30 C (datasheet convention).

    30°C
    Industrial Solar GmbH, Technical Data LF-11 - reference conditions.

  • Hard domain limit: a requested steam temperature above it is refused by the input guard rather than extrapolated.

    Market range 400 C for evacuated-receiver LFR; 550 C+ only with molten salt or PTC.

    400°C
    Industrial Solar GmbH, Technical Data LF-11 - 'Maximum operating temperature: 400 C', process heat 100 kW to 10 MW.

  • Standard pressure rating of the collector loop; the upper bound of the pressure input and a hard domain guard.

    Market range 40 bar standard, up to 120 bar on request.

    40bar
    Industrial Solar GmbH, Technical Data LF-11 - 'pressures up to 120 bar (standard 40 bar)'.

  • Granularity of a real field: the module count output rounds the requested aperture up to whole modules (reporting only - the cost model stays on the requested aperture).

    Market range 22 m2 per LF-11 basic module.

    22m2
    Industrial Solar GmbH, Technical Data LF-11 - 'Aperture surface of primary reflectors 22 m2' per basic module (11 reflector units).

  • Physical ceiling on how tightly rows can be packed; cross-checks the land use factor (1/0.67 = 1.49 m2 of ground per m2 of aperture at maximum density).

    0.67ratio
    Industrial Solar GmbH, Technical Data LF-11 - 'maximum packing density (aperture area/ground area) of 67%'.

  • Technical life of the collector; grounds the lower bound of the economic lifetime input.

    20years
    Industrial Solar GmbH, Technical Data LF-11 - 'Life expectancy +20 years'.

  • Default auxiliary electric draw per m2 of aperture; the matching input is the adjustable upstream knob of the electricity inlet.

    1.7W/m2
    Industrial Solar GmbH, Technical Data LF-11 - 'Electrical peak consumption (16 Modules): < 600 W'; 600 W / (16 x 22 m2) = 1.70 W/m2 of aperture (tracking and control, excludes feedwater pumping).

  • Ground area needed per m2 of aperture at the row spacing used in the source study; the land output lets a user check the site actually fits.

    Market range 1.3 at study spacing, 1.49 at the LF-11 maximum packing density.

    1.3m2/m2
    Famiglietti & Abbas, Solar 2025, 5, 27, Eq. (11) - F_land = W_gr/W_a = 6.5/5.0 = 1.3 for the CST field.

  • DNI-weighted mean irradiance while the field is operating. It converts an annual irradiation into operating hours, which is what the receiver loss term must be integrated over - losses scale with TIME, not with irradiation.

    720W/m2
    DERIVED: 2100 kWh/m2/yr (Spain DNI, IRENA) divided by 2917 h/yr (AEMET normal sunshine duration, Sevilla Aeropuerto 1981-2010) = 719.9 W/m2.

  • Numerator of the mean operating irradiance derivation, and the reference high-DNI site of the literature this model is calibrated against.

    2100kWh/m2/year
    IRENA, 'Renewable Energy Technologies: Cost Analysis Series - Concentrating Solar Power' (2012) - 'a site in Spain with a DNI of 2 100 kWh/m2/year'.

  • Denominator of the mean operating irradiance derivation.

    2917h/year
    AEMET, Valores climatologicos normales, Sevilla Aeropuerto 1981-2010 - monthly insolation 183, 189, 220, 238, 293, 317, 354, 328, 244, 216, 181, 154 h; annual sum 2917 h.

  • Grounds the ~20 C nominal ambient temperature used in the receiver loss term.

    19.2°C
    AEMET, Valores climatologicos normales, Sevilla Aeropuerto 1981-2010 - annual mean temperature 19.2 C.

  • Saturation temperature is inverted from the delivery pressure with this Antoine set.

    Market range Valid 379-573 K, i.e. 106-300 C, which covers 1-85 bar.

    3.55959
    NIST Chemistry WebBook, Antoine parameters for water (Liu and Lindsay, 1970), valid 379-573 K: log10(P_bar) = A - B/(T_K + C).

  • Second Antoine coefficient.

    Market range Valid 379-573 K.

    643.748K
    NIST Chemistry WebBook, Antoine parameters for water (Liu and Lindsay, 1970), 379-573 K.

  • Third Antoine coefficient.

    Market range Valid 379-573 K.

    -198.043K
    NIST Chemistry WebBook, Antoine parameters for water (Liu and Lindsay, 1970), 379-573 K.

  • Reference point used to quantify the Antoine approximation error: this model returns 209.9 C at 20 bar, i.e. -2.5 K.

    Market range Exact reference value.

    212.38°C
    NIST Chemistry WebBook, water saturation table (IAPWS-95) - 20 bar: T_sat 212.38 C.

  • Second reference point for the Antoine error: this model returns 253.75 C at 40 bar, i.e. +3.4 K. Across 6-40 bar the deviation stays within -3.5 K to +3.4 K, which moves the final LCOH by less than 0.2 % because T_sat only feeds the loss term (~6 % of the energy balance).

    Market range Exact reference value.

    250.35°C
    NIST Chemistry WebBook, water saturation table (IAPWS-95) - 40 bar: T_sat 250.35 C.

  • Flat saturated-steam enthalpy. Cross-validated against DOE Steam Tip Sheet #15 Table 1 to within 0.07-0.95 % over 150-600 psig and 50-250 F feedwater.

    2780kJ/kg
    NIST Chemistry WebBook, water saturation properties (IAPWS-95): h_g = 2748.1 kJ/kg at 5 bar, 2798.3 at 20 bar, 2800.8 at 40 bar - 2780 kJ/kg is the mean over 6-40 bar.

  • Low-pressure end of the enthalpy band the flat 2780 kJ/kg approximates.

    Market range Exact reference value.

    2,748.1kJ/kg
    NIST Chemistry WebBook, water saturation table (IAPWS-95).

  • Mid-range check point of the enthalpy approximation.

    Market range Exact reference value.

    2,798.3kJ/kg
    NIST Chemistry WebBook, water saturation table (IAPWS-95) - 20 bar: h_f 908.50, h_g 2798.3 kJ/kg.

  • High-pressure end of the enthalpy band.

    Market range Exact reference value.

    2,800.8kJ/kg
    NIST Chemistry WebBook, water saturation table (IAPWS-95) - 40 bar: h_g 2800.8 kJ/kg.

  • Mean specific heat of superheated steam used to price the superheat above saturation.

    2.5kJ/kg/K
    NIST Chemistry WebBook, water isobar at 20 bar (IAPWS-95): h = 2798.3 kJ/kg at T_sat 212.38 C, 3024.2 at 300 C, 3137.7 at 350 C -> mean cp 2.58 over 88 K of superheat and 2.47 over 138 K.

  • Feedwater enthalpy is modelled as cp x T_feedwater, the same convention as the DOE steam benchmark.

    4.187kJ/kg/K
    NIST Chemistry WebBook, liquid water enthalpy along the saturation line (IAPWS-95): h_f 640.09 kJ/kg at 151.83 C, 908.50 at 212.38 C -> ~4.19 kJ/kg/K.

  • Bridge between the DOE table (Btu/lb) and this model (kJ/kg).

    Market range Exact.

    2.326kJ.lb/(kg.Btu)
    Exact unit conversion (1 Btu_IT/lb = 2.326 kJ/kg), used to cross-check the steam enthalpy model against the DOE steam tip sheet.

  • Validation point of the enthalpy rise model: this calculator returns 2389.2 kJ/kg, -0.08 %.

    Market range Exact tabulated value.

    1028Btu/lb
    U.S. DOE, Steam Tip Sheet #15 'Benchmark the Fuel Cost of Steam Generation', Table 1 - 150 psig with 200 F feedwater = 1028 Btu/lb (2391.1 kJ/kg).

  • Second validation point of the enthalpy rise model: this calculator returns 2621.8 kJ/kg, -0.07 %.

    Market range Exact tabulated value.

    1128Btu/lb
    U.S. DOE, Steam Tip Sheet #15, Table 1 - 150 psig with 100 F feedwater = 1128 Btu/lb (2623.7 kJ/kg).

  • Default installed cost per m2 of aperture. It is an INSTALLED solar-field cost, which is why the meta declares battery_limit = installed and no installation or owner factor is applied on top.

    304EUR/m2
    AI

  • Grounds the lower bound of the CAPEX input range with a documented real total investment.

    241.8EUR/m2
    Filali Baba Y., Ajdad H., Al Mers A., Bouatem A., Bououlid Idrissi B., El Alj S. (2020), 'Preliminary cost-effectiveness assessment of a Linear Fresnel Concentrator: Case studies', Case Studies in Thermal Engineering, DOI 10.1016/j.csite.2020.100730 - total investment cost of 241.8 EUR/m2 for one of its cases. The LCOH of 29.7 EUR/MWh_th previously quoted alongside is NOT in this paper, whose economic indicator is the payback period; that figure has been dropped.

  • Independent LCOH point this calculator is sanity-checked against (45.7 EUR/MWh_th nominal at a more conservative 304 EUR/m2 and DNI 1900).

    34.1EUR/MWh_th
    Attribution corrected and NOT re-established: the study cited until now (Filali Baba Y., Ajdad H., Al Mers A., Bouatem A., Bououlid Idrissi B., El Alj S. (2020), 'Preliminary cost-effectiveness assessment of a Linear Fresnel Concentrator: Case studies', Case Studies in Thermal Engineering, DOI 10.1016/j.csite.2020.100730) reports payback periods, not LCOH, so it cannot carry the 34.1 against 36.9 EUR/MWh_th comparison for Spain. The primary source of this figure was not established in this build.

  • Default annual O&M as a share of CAPEX. It covers FIELD maintenance and operation ONLY (mirror washing, tracking, controls, inspection): make-up feed and auxiliary power are declared as project inlets and must never be booked here as well.

    0.021/year
    Famiglietti & Abbas, Solar 2025, 5, 27, Section 2.4 - 'OPEX = 0.02 CAPEX is a widely accepted assumption in solar systems'.

  • Default real discount rate, matching the source study's LCOH definition.

    0.05ratio
    Famiglietti & Abbas, Solar 2025, 5, 27, Section 2.4 - 'assuming r_dis = 0.05, n_y = 25 years'.

  • Default economic lifetime, above the 20-year collector technical life quoted by the manufacturer.

    25years
    Famiglietti & Abbas, Solar 2025, 5, 27, Section 2.4 - n_y = 25 years.

  • Lower edge of the documented SHIP cost band; the band-position output places this plant inside it.

    Market range 30 EUR/MWh_th under favourable conditions.

    30EUR/MWh_th
    IEA SHC Task 64, Technology Position Paper: Solar Heat for Industrial Processes (January 2024) - 'the levelized cost of heat (LCOH) of implemented SHIP plants is typically 30 to 70 EUR/MWh'.

  • Upper edge of the documented SHIP cost band.

    Market range 70 EUR/MWh_th at the unfavourable end.

    70EUR/MWh_th
    IEA SHC Task 64, Technology Position Paper: SHIP (January 2024) - competitive LCOH of 30-70 EUR/MWh; installed cost reductions of 20 to 55 % documented over ten years.

  • Market yardstick for the specific yield output: a concentrating field on DNI 1900 should sit above the SHIP fleet average, which is dominated by non-tracking collectors on lower irradiation.

    550kWh/m2/year
    IEA SHC Task 64, Technology Position Paper: SHIP (January 2024) - 'Assuming specific solar useful heat delivery of 550 kWh/m2/yr'.

  • Irradiation basis of the Task 49 potential study used as a lower sanity bound (1200 x 0.40 = 480 kWh/m2/yr).

    Market range 1200 kWh/m2/yr European average plane-of-array irradiation.

    1200kWh/m2/year
    IEA SHC Task 64 position paper citing IEA SHC Task 49 potential studies - 'Irradiation of 1,200 kWh/(m2a), 40% annual efficiency'.

  • Annual efficiency of the Task 49 potential study; this calculator returns 31.9 % on DNI, a stricter denominator than plane-of-array irradiation.

    0.4ratio
    IEA SHC Task 64 position paper citing IEA SHC Task 49 - 40 % annual field efficiency.

  • Design target for the solar fraction output: without storage, a field sized for 30 % of demand is a conservative first cut and 50 %+ is documented as achievable.

    50%
    IEA SHC Task 64, Technology Position Paper: SHIP (January 2024) - 'Properly sized systems reach solar fractions above 50%'.

  • Grounds why the DNI input starts at 1600 and is defaulted at 1900: below that threshold a concentrating field loses to a gas boiler and the answer stops being defendable.

    1900kWh/m2/year
    Filali Baba Y., Ajdad H., Al Mers A., Bouatem A., Bououlid Idrissi B., El Alj S. (2020), 'Preliminary cost-effectiveness assessment of a Linear Fresnel Concentrator: Case studies', Case Studies in Thermal Engineering, DOI 10.1016/j.csite.2020.100730 - the study does assess competitiveness against fossil fuel as a function of DNI, which is where this threshold comes from in spirit; the precise pairing of 1900 kWh/m2/yr with a specific cost under 150 EUR/m2 was not verified against its text in this build.

Sources

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