“…The spectrum of synthetic oxygenated fuels accessible through biomass or CO 2 conversion (see also Section ) is large, including further ethers, alcohols, aldehydes, ketones, furan derivatives, and other compounds, ,,− ,, and offers not only GHG reductions but may contribute to reduced emissions of local pollutants and improved combustion performance with an option to select and design the fuel for the respective purpose. , With interesting synthesis routes and potential fuels emerging, ignition properties, reactivity, flame structure, combustion emissions, and other relevant performance indicators, potentially for blends with conventional fuels, must be further examined for relevant process conditions, including a comprehensive assessment of the entire process. Regarding carbon neutrality, the number of carbon atoms released by combustion should not exceed the number of carbon atoms taken from the environment, and energy input should be from renewable sources .…”