energy_mass_balanceequipment_sizingcostingefuel
Screening model for an ethanol drying + vaporisation + catalytic dehydration unit producing light olefins for downstream jet-fuel synthesis, including mass balance, utility demands, plot space, and scaled CAPEX/OPEX with levelized cost.
Selects default energy intensity, catalyst productivity proxy (WHSV), and CAPEX reference for screening.
Overall mass yield of light olefins per ethanol feed (wt% of ethanol in). Must be below the stoichiometric maximum for dehydration.
Average annual utilisation of the ETO unit. Used to compute load hours and part-load utility penalty.
min 10 · max 100 · step 1 · %
Wet ethanol feed to the ETO front-end unit on an as-received mass basis (screening approximation).
min 0.1 · max 200 · step 0.1 · t/h
Light olefins product flow
Main product stream to downstream upgrading
Annual ethanol need (for olefins conversion)
Ethanol actually consumed to form olefins (excludes offgas/unconverted)
Annual olefins production
Main annual output basis for levelized cost
Reaction water produced
Water formed by dehydration chemistry (separated downstream)
Offgas / other products (mass balance remainder)
Represents unconverted ethanol + side products + losses (lumped)
Electricity demand (average at design throughput)
Includes drying, pumps, compression/conditioning (lumped)
Annual electricity consumption
Scaled by capacity factor (load hours)
Heat demand (average at design throughput)
Primarily vaporisation + reactor duty (lumped)
Annual heat consumption
Scaled by capacity factor (load hours)
Number of parallel trains
Based on a maximum practical train throughput
Plot space requirement
Includes integration and access margin
Equipment purchase cost (EPC, purchase only)
Excludes installation, indirects, and owner’s costs
Total installed CAPEX (TIC)
Scaled with capacity; technology-dependent reference point
Fixed O&M cost
Labor + maintenance + overhead (fraction of installed CAPEX)
Annualized catalyst replacement cost
Straight-line annualization over replacement interval
Levelized cost of olefins (energy basis, LHV)
Uses a representative olefins LHV to express EUR/MWh-LHV
Levelized cost of olefins (gate cost)
Levelized cost per tonne of olefins produced
Amortization period used in the capital recovery factor.
min 5 · max 40 · step 1 · years
Optional: include ethanol feedstock cost in total annual cost. Set to 0 for a tolling/processing-only view.
Used in CRF for annualizing CAPEX.
Grid or contracted electricity price used to value annual electricity consumption.
Price for steam/thermal energy (e.g., natural gas boiler, waste heat credit, or steam import).
Calculator context
This calculator provides a pre-feasibility (screening-stage) model for an Ethanol-to-Olefins (ETO) front-end conversion asset covering ethanol drying, vaporisation, catalytic dehydration, water separation, olefin conditioning, and transfer to downstream processing (e.g., oligomerization/hydrogenation for ATJ / e-kerosene). It is a global, generic estimator intended for early concept comparison, using mass-balance stoichiometry, simple equipment sizing heuristics, and standard cost-scaling methods consistent with IEA/IRENA/NREL-style techno-economic modelling.
The model is built on an hourly design basis with annualization using capacity factor. Core steps:
Operating time
Mass balance (overall ETO lumped yield)
Utilities (energy intensity with part-load penalty)
Costing and finance (standard chemical scaling; see e.g., Peters & Timmerhaus approach used in many NREL/IEA TEAs)
43 assumptions used in the calculations
Prevents divide-by-zero and non-finite results during scaling and annualization.
Market range Not applicable
Standard conversion from capacity factor to annual operating hours.
Market range 8760 h/year
Avoids inline numeric literals in DSL expressions.
Market range Not applicable
Represents reduced efficiency at low utilisation (start/stop, fixed losses). Used for screening only.
Prevents unrealistically large penalties at low utilisation for early-stage models.
Constrains user input to physically plausible mass yield for dehydration-dominated pathways.
Market range Up to ~60.9%
Used to infer ethanol consumed to form olefins to close the mass balance and estimate offgas remainder.
Market range 1.64 (stoichiometric for dehydration basis)
Allows explicit reporting of reaction water for separation and downstream water handling.
Market range 0.64 (stoichiometric)
Provides optional linkage to the e-fuels scaffold by estimating upstream CO2 demand embodied in ethanol throughput (outside ETO unit scope).
Market range 1.91 (stoichiometric)
Supports e-fuels context by estimating upstream green H2 embodied in ethanol throughput (outside ETO unit scope).
Market range 0.26 (stoichiometric)
Converts kW to MW and kWh to MWh.
Market range 1000
Captures balance-of-plant electric loads at pre-feasibility level.
Assumes slightly higher compression/conditioning needs and tighter controls.
Intermediate between alumina and zeolite cases.
Represents net heat import after basic heat integration at concept level.
Assumes improved conversion/selectivity and somewhat better heat integration potential.
Intermediate between alumina and zeolite cases.
Enforces parallel trains for large capacities to reflect equipment/operability constraints at screening stage.
Provides order-of-magnitude plot footprint for layout screening.
Captures non-linear footprint growth with throughput (larger vessels, more auxiliaries).
Normalizes the power-law plot scaling to a reasonable mid-size train.
Similar to cost exponents; reflects economies of scale but not linear.
Accounts for pipe-racks, access ways, firefighting clearance, and tie-ins at concept stage.
Defines the anchor point for power-law scaling of specific CAPEX and O&M fractions.
Represents lumped installed cost for drying/vaporisation/reactor/separation/conditioning for early comparisons.
Higher cost case reflecting catalyst system complexity and/or tighter separations.
Intermediate CAPEX between alumina and zeolite options.
Represents typical chemical process scale economies (cost grows sub-linearly with capacity).
Prevents unrealistically low specific costs at large scale in a screening model.
Prevents unrealistically high specific costs at very small scale in a screening model.
Converts purchased equipment cost to total installed cost including piping, E&I, civil, and indirects at screening level.
Represents labor/maintenance/overhead for continuous chemical process units at concept stage.
Allows slightly lower O&M fraction at larger scale while keeping within clamps.
Prevents unrealistic staffing/maintenance underestimation at scale.
Avoids unrealistic O&M inflation at small scale in screening models.
Used only to estimate catalyst inventory for replacement cost and rough reactor sizing metrics.
Assumes higher activity/productivity than alumina for sizing purposes.
Intermediate productivity assumption.
Converts catalyst volume to mass for replacement cost estimation.
Order-of-magnitude annualized replacement cost; not intended for procurement accuracy.
Represents periodic replacement due to deactivation/coking at industrial operation.
Enables expressing levelized cost on an energy basis for fuel-chain comparisons.
Converts MJ to MWh for LHV-based normalization.
Market range 3600
