Impact of OMEx e-fuels for CO2 emissions abatement in light-duty commercial vehicles

E-fuels, such as oxymethylene dimethyl ethers (OME x ), represent a promising alternative to conventional fuels to reduce engine emissions and extend their durability. They are highly oxygenated fuels that allow emissions reduction because of smoke-free combustion. Recent studies have highlighted that adopting scaled injection systems can overcome their lower energy content. The aim of this work is to provide a preliminary well-to-wheel (WTW) analysis by merging the most recent literature findings concerning well-to-tank (WTT) with a detailed tank-to-wheels (TTW) assessment. The analysis considers different OME x types and diesel/OME x blends to compute energy demand, fuel consumption, and carbon dioxide emissions of a delivery van subject to a given driving cycle. From literature evidence, the average improvement in engine efficiency attained by using pure OME x fuels has been estimated to be approximately 4.5% compared to pure diesel, with greater values for short-chain OME x (e.g., up to 10%). From the obtained results, a reduction in tank energy requirement was observed, with a minimum of -10% for pure OME 2 . However, fuel consumption increases because of OME x lower energy content, showing a growth ranging from 74% to 140% in mass and from 65% to 86% in volume with increasing chain length of pure OME x . The variation in CO 2 emissions is not univocal, since a reduction of almost −4% for pure OME 1 and an increase above 20% for pure OME 4 were achieved. The obtained results highlight how OME x with shorter chains can lead to greater efficiencies compared to pure diesel, with a slight reduction in CO 2 emissions.