Life Cycle Water Footprint Analysis and Future Prediction Based on LSTM for Arundo donax in Sustainable Aviation Fuel Production

Under the background of the energy revolution and achieving net-zero carbon emissions, biofuels are regarded as a feasible and effective way to reduce carbon emissions. However, whether the use of biofuel will exacerbate the shortage of freshosources remains unclear. To compare the water requirements of biofuels and fossil fuels, we analyzed the life cycle water footprint (WFt) and carbon footprint when preparing sustainable aviation fuel (SAF) from Arundo donax in Baicheng, Xinjiang, China. We also predicted the water footprint (WF) of Baicheng over the next 20 years based on the long short-term memory (LSTM) model. Meanwhile, to improve the accuracy of the predictions, this study adjusted the water footprint calculation method. The data come from predication showed that the WFt of Arundo donax in the Baicheng area ranged from 0.1902 to 0.1910 m(3)/MJ, the WFt of cottonseed and petroleum are 0.2117 m(3)/MJ and 0.0793 m(3)/MJ, respectively. The core life cycle assessment (LCA) value was 1.051 g CO2/MJ. Overall, compared to fossil fuels, biofuels have a larger WF and reduce carbon emissions. Combining the predicted data with future developments, the WFt in this region showed a downward trend. From a practical perspective, based on the WF, carbon footprint, climate, and soil conditions in Xinjiang, Arundo donax is a suitable feedstock for bio-based aviation fuel and can be widely promoted in this area. However, further improvements in various aspects are required.