E-fuels, or electro fuels, are synthetic fuels produced using renewable electricity, water, and captured carbon dioxide. Through a process called Power-to-Liquid (PtL), green hydrogen is generated via electrolysis and then combined with CO2 to create liquid hydrocarbons like synthetic gasoline, diesel, or jet fuel. These fuels are carbon-neutral when produced sustainably and can be used in existing internal combustion engines and fuel infrastructure, making them a promising solution for decarbonizing hard-to-electrify sectors like aviation, shipping, and heavy transport.