The sophistication, power and efficiency of the internal-combustion engine continues to improve year-to-year, making prognostications of the demise of the ICE engine seem further and further out. From a hardware standpoint, automakers have implemented highly sophisticated hardware to meet ever-stricter fuel economy and emissions regulations, but the one area they can't directly control is fuel quality. The Environmental Protection Agency phased in ultra-low-sulfur diesel fuel starting in 2007, and is proposing to do the same with gasoline starting in 2017, bringing the allowable sulfur levels from 30 parts per million (PPM) to 10 PPM, according to a Bloomberg report.
Automakers favor the implementation of the stricter fuel standards since gasoline sold in Europe and Japan already meets the lower-sulfur standard, and could design engines for a global standard, rather than calibrating them for regional variations in fuel. Already, there are state-to-state differences in emissions standards, although EPA standards have lately been converging to meet the stricter standards set by California and followed by a handful of other states.
Naturally, the oil companies oppose the change, and claim that it will cost the industry an estimated $10 billion in capital costs and $2.4 billion in annual compliance costs. The EPA claims the new standards will prevent as many as 2400 premature deaths per year by 2030, and result in a net savings of up to $23 billion in saved health care costs and other net benefits.
The emergence of gasoline direct-injected engines has brought the issue into the limelight. GDI engines generally deliver lower carbon dioxide emissions due to their higher fuel efficiency, but have recently come under scrutiny for their higher particulate emissions relative to port-injected engines.