# Solar-driven direct air capture to produce sustainable aviation fuel

## TL;DR

This paper proposes a solar-powered method to capture CO2 from the air and convert it into sustainable aviation fuel, reducing emissions and energy costs.

## Contribution

A solar-driven process for direct air capture and on-site conversion to sustainable aviation fuel is introduced.

## Key findings

- Replacing fossil-fuel heating with solar thermal energy reduces electricity use by 63% and onsite CO2 emissions by 59%.
- The sustainable aviation fuel production cost is US$4.62/kg, making it cost-effective.
- Favorable deployment locations are low-risk countries with high solar irradiance and low hydrogen costs.

## Abstract

Renewable energy-powered direct air capture with subsequent utilisation offers a sustainable decarbonisation strategy for a circular economy. Whereas current liquid-based capture technology relies on natural gas combustion for high-temperature calcination, restricting the transition to fully renewable operation. In this study, we show a 1MtCO2/year solar-driven process that adopts a hydrogen fluidised solar calciner with onsite catalytic conversion of CO2 into sustainable aviation fuel. We find that replacing fossil-fuel heating with solar thermal energy lowers electricity consumption by 63% and reduces onsite CO2 emissions by 59%. The analysis shows that the production cost of sustainable aviation fuel is cost-effective (US$4.62/kg) compared to the conventional process. Geographical sensitivity analysis indicates favourable deployment locations are low-risk countries with high solar irradiance and low hydrogen cost. The predicted results also outline potential economic viability for policymakers and industry investors.

Liquid-based direct air capture relies on natural gas combustion to drive calcination. Here, the authors present a solar-driven hydrogen-fluidized solar calciner integrated with on-site CO₂ conversion to produce sustainable aviation fuel. The analysis shows its economic feasibility.