IJER editorial: The future of the internal combustion engine

Executive summaryInternal combustion (IC) engines operating on fossilfuel oil provide about 25% of the world’s power (about3000 out of 13,000 million tons oil equivalent peryear—see Figure 1), and in doing so, they produceabout 10% of the world’s greenhouse gas (GHG) emis-sions (Figure 2). Reducing fuel consumption and emis-sions has been the goal of engine researchers andmanufacturers for years, as can be seen in the twodecades of ground-breaking peer-reviewed articles pub-lished in thisInternational Journal of Engine Research(IJER). Indeed, major advances have been made, mak-ing today’s IC engine a technological marvel. However,recently, the reputation of IC engines has been dealt asevere blow by emission scandals that threaten the abil-ity of this technology to make significant and furthercontributions to the reduction of transportation sectoremissions. In response, there have been proposals toreplace vehicle IC engines with electric-drives with theintended goals of further reducing fuel consumptionand emissions, and to decrease vehicle GHG emissions.Indeed, some potential students and researchers arebeing dissuaded from seeking careers in IC engineresearch due to disparaging statements made in thepopular press and elsewhere that disproportionatelyblame IC engines for increasing atmospheric GHGs.Without a continuous influx of enthusiastic, well-trained engineers into the profession, the potential fur-ther benefits that improved IC engines can still providewill not be realized. As responsible automotive engi-neers and as stewards of the environment for futuregenerations, it is up to our community to make an hon-est assessment of the progress made in the developmentof IC engines over the past century, with their almostuniversal adoption to meet the world’s mobility andpower generation needs. Considering that the maturityof IC engine technology is something that many othertechnologies/possibilities do not have, we also need toassess the potential for future progress, as well as toassess the benefits offered by competitor technologies,in order to make responsible recommendations forfuture directions.