From air to Jet Fuel: Techno-economic and sustainability analysis of eSAF production using direct air capture and chloralkali electrolysis

[Geoengineering News]

https://www.sciencedirect.com/science/article/abs/pii/S0196890426001810

Authors: Amit Kumar, Arun Kumar Tiwari, Dia Milani, William Kubic, Deóis UaCearnaigh

17 February 2026

https://doi.org/10.1016/j.enconman.2026.121212

Highlights

•Integrated DAC–chlor-alkali electrolysis enables negative-carbon eSAF.

•Chlor-alkali electrolysis enables co-production of fuels and chemicals.

•Co-production of chemicals improves overall eSAF process economics.

Abstract

In recent years, Sustainable Aviation Fuel (SAF) has gained significant attention due to the increasing environmental and regulatory pressure to reduce greenhouse gas (GHG) emissions from the aviation sector. This study evaluates the feasibility of a novel renewable-powered electro synthetic SAF synthesis (eSAF) framework. The proposed framework integrates a modified absorption-based direct air capture (DAC) system with chlor-alkali electrolysis to produce the intermediate syngas to be ultimately used in Fischer-Tropsch (FT) based eSAF production. This paper explores the use of a pH swing, cold capture process in DAC for capturing carbon dioxide (CO2) from atmospheric air, while the chlor-alkali electrolysis process generates H2 gas from seawater, enabling the co-production of syngas precursors from renewable feedstocks. The optimisation work reported in this study aims to minimize the cost of hydrogen storage by producing eMethane as an intermediate product via the Sabatier reaction. This allows eMethane to be used in a reduced capacity, down-sized FT reactor operated in continuous mode to produce FT-based eSAF. In addition to eSAF, the proposed framework produces valuable co-products, including sodium chlorate, technical-grade distilled water, process steam, and over-captured CO2 suitable for geological storage (GSC), which support achieving cost parity for eSAF production with fossil-based counterpart technologies. Aspen Plus Economic Analyzer (APEA) estimates the capital expenditure (CAPEX) for the first-of-a-kind facility at ∼$162 million, with an annual production capacity of 2,760 tonnes of eSAF and∼20 kt of excess CO2 capture, consuming∼26 MWe of wind& solar power. The operational expenditure (OPEX) is initially estimated at ∼$12 million per year, subject to escalation over time. A detailed economic analysis, incorporating factors such as contingency, cost escalation, and plant depreciation, indicates a projected payback period (PBP) of 12years. The proposed framework achieves a negative carbon intensity of –165 gCO2/MJ for the produced eSAF when aligned with the United Kingdom’s GHG emissions accounting criteria for SAF under the Renewable Transport Fuel Obligation (RTFO), representing a significant carbon reduction strategy compared to the +131 gCO2/MJ of the conventional Jet-A fuel production. This innovative integration of DAC and chlor-alkali electrolysis demonstrates a viable pathway for scalable, energy-efficient, and economically competitive eSAF production that is well-aligned with the UN’s sustainable development goals.

Source: ScienceDirect