Alternative fuels of today for sustainable mobility of tomorrow

Abstract

In recent years, Greenhouse gas (GHG) reduction has become the major driver for new technological developments in the transportation sector since CO2 emissions emitted by vehicles represent a significant part. In Europe for example, Greenhouse gases produced by Road Transportation comprise about 20% of anthropogenic CO₂, which is only 5% less than the biggest contribution coming from Heat and Electricity production. Although GHG emissions in Europe tend to go down, further efforts have to be undertaken in order to reduce the CO₂(+CH₄/N₂O)-concentration in the atmosphere even more in order to limit global warming. For 2030, the European Commission has targeted a CO₂- reduction of 40% compared to 1990 levels which also implies a stepwise reduction in fleet-averaged CO₂ levels for newly registered passenger car vehicles. In 2021 therefore a fleet average of 95 g/km was fixed which would correspond to 4.1 litre gasoline or 3.6 litre Diesel per 100 kilometres. Due to thermodynamical limitations, those numbers will not be achievable with conventional Diesel and Gasoline-based powertrain technology alone, which implies the necessity for OEMs to develop and apply new technology in order to provide sustainable, profitable and attractive vehicle solutions. Beside disruptive powertrain solutions such as battery electric vehicles, which require high investments in production and infrastructure development, there are also new more evolutionary powertrain concepts based on Low-Carbon-fuels, which do have a lot of promising features. If those new fuels are carefully selected, existing powertrain technology could be preserved with small modifications in fuel and tank system, which of course would strongly reduce required manufacturing investments. Even vehicles, which are already on the market could contribute to a sustainable mobility if the chosen fuels are compatible with conventional powertrain technology,