What the model leaves out

Every result in the app carries these omissions. Both stages’ How it works tabs end with this page; the stages themselves are explained in How prefeasibility works and How feasibility works.

Process heat

No thermal requirements are modelled — at any stage, by either engine. There is no heat carrier in the model: the linear program has exactly two buses, electricity and hydrogen. Every energy figure the app reports is electricity, so a chain with a real process-heat duty needs more energy than we show. For the eSAF routes the reference puts that duty at about 4.0 MWh of heat per tonne of jet on the Fischer-Tropsch route and 5.4 on methanol-to-jet, roughly 95% of it in CO₂ purification; met electrically it would add ~10% and ~18% to those routes’ total electricity. For ammonia, the parasitic baseloads and the on-site steam generation are both excluded, and they partly offset each other. These are known omissions, not rounding — the eSAF one is large enough to narrow the gap between the two pathways.