Power-to-Liquids (PtL) Sustainable Aviation Fuel (SAF), produced from renewable hydrogen and captured CO₂, is a key pathway for aviation decarbonisation. However, large-scale deployment remains constrained by limited operational data at intermediate scales and uncertainty in key cost drivers, including electricity sourcing, utility requirements, and product upgrading and separation.
This work addresses these gaps by coupling a techno-economic assessment (TEA) with experimental results and validated operating envelopes from a first-of-its-scale Italian pilot Fischer–Tropsch (FT) unit. The pilot converts syngas into hydrocarbons and separates products into four streams (waxes, water/alcohols, liquid hydrocarbons, and light gases), providing realistic insight into process operability and utility demand.
The system features a compact tubular FT reactor (1 m catalytic section, ~3 cm diameter) with enhanced heat management, operating at 15–30 barg and 210–230 °C, and processing syngas at ~1 kg/h with H₂/CO ratios of 2–2.5. The separation train includes a high-temperature wax separator (>120 °C) and a low-temperature three-phase separation (~0 °C) enabled by a water–glycol refrigeration loop. Continuous campaigns of up to 120 hours, supported by dedicated product hold-up volumes, generate critical data for realistic scale-up, particularly for thermal management, wax handling, and separation logistics.
These pilot-derived constraints and utility requirements (heating, cooling, diathermic oil recirculation, trace heating) are integrated into a TEA framework based on detailed process simulation and cost modelling using Aspen HYSYS and Aspen Process Economic Analyzer. The analysis evaluates CAPEX, OPEX, and Levelized Cost of Production (LCoP) under electricity supply configurations aligned with RFNBO compliance, including PV-coupled and grid-based renewable scenarios.
Results identify electricity as the dominant cost driver and quantify investment sensitivity to power configuration. The FT-based PtL route yields an LCoP of 8–10 €/kg across the investigated scenarios, providing an evidence-based cost range grounded in real operational constraints rather than simulation-only assumptions.
Overall, the study demonstrates how pilot-scale validation significantly reduces scale-up uncertainty and enables more credible TEA outcomes for investment and policy decision-making. This integrated approach offers a replicable pathway to advance PtL SAF from laboratory-scale modelling toward bankable, site-specific project development in Italy and comparable markets.