This paper provides a thorough evaluation of emerging e-fuel technologies, namely e-FT (Fischer-Tropsch) fuels and e-MTG (Methanol-to-Gasoline), as credible substitutes for traditional fossil fuels in Saudi Arabia's energy landscape. Amid a global pivot towards more sustainable and low-carbon energy solutions, this study aims to quantify the environmental benefits of adopting these e-fuels within the framework of Saudi Arabia's initiatives to diversify its energy portfolio and curtail greenhouse gas emissions. Utilizing a comprehensive well-to-wheel analysis, the research incorporates various methods for hydrogen production as well as carbon capture techniques. We present two distinct technology scenarios, targeting the years 2030 and 2060, to evaluate the capacity of e-fuels in aiding Saudi Arabia's transition towards a low-carbon energy infrastructure. In addition, the paper compares the carbon reduction efficacy of e-fuels against that of conventional diesel/gasoline fuels. This study offers invaluable perspectives for policymakers, energy analysts, and investors, shedding light on the viability of e-FT and e-MTG technologies in mitigating the environmental footprint of Saudi Arabia's energy sector.

Water emulsified fuels produced by controlled cavitation technology offer a stable and homogeneous fuel for the combustion of heavy fuel oils (HFOs). The emulsified fuel has advantages such as secondary atomization, high level of combustion, and lower emission of pollutants. This project is aimed at characterizing emulsions produced by the controlled cavitation technology (hydrodynamic cavitation) method, by Pacific Green. Two pairs of fuels/emulsions ULSFO (before and after) and VLSFO (before and after) were tested. Techniques employed for characterization of these fuel/emulsions were combustion (TGA, Pyro GC x GC, FTICR-MS), microscopy (cryo-SEM, optical), and engine-based testing. The TGA revealed that the ULSFO (before and after) exhibit no changes in behaviour, whereas the VLSFO (before and after) exhibit changes in thermal behaviour. Further testing with Pyro GC x GC a pyrolysis based technique, revealed the same trend: where the ULSFO exhibited no changes and VLSFO exhibits changes. Further it was seen that the reactivity/emission of S was lower for the VLSFO emulsion. Microscopy based techniques showed a non-uniform distribution of water droplets, which is suggestive of lesser intense cavitation in creating the emulsion. Two broad classes of characterization (combustion and microscopy) indicate that samples of VLSFO are distinguishable, and there is a lower emission. And the cavitation-based method has no observable effect on ULSFO. Further work, on Engine testing will be carried out at Uni. of Lund in the coming months on a six-cylinder Scania D13 to complete the characterization of these emulsions.