Hyundai described its plans Tuesday regarding the future of its internal combustion engines under an internal program designed "Smart Stream." This program intends to integrate a variety of advanced technologies into Hyundai's future engines to increase fuel economy and reduce greenhouse gas emissions, and its developments are intended to be applied to the entire range of Hyundai Motor group products.
Stated technologies include "Continuously Variable Valve Duration," and the use of an eight-speed, dual-clutch transmission. The rollout is slated to encompass 16 engines (10 gasoline, six diesel) and six transmissions between today and 2022. Most importantly, Hyundai mentioned a thermal efficiency target that has huge implications for the future of road cars.
Hyundai said it "aims to maximize thermal efficiency by up to 50 percent in the future," referring to how much potential energy from fuel and air is captured and used as it enters the combustion chamber for propulsion.
The Drive contacted Hyundai to clarify whether this meant a 50 percent increase over existing levels, or a flat 50 percent target. A spokesperson responded with confirmation that Hyundai intends to extract 50 percent thermal efficiency from its Smart Stream engines.
"The goal is to increase from absolute 35-39% to absolute 50% (it is not additive). We won’t increase thermal efficiency an additional 50%," said the Hyundai spokesperson.
The significance to this thermal efficiency target is just how high it is. Mercedes' Formula 1 program reached this approximate efficiency level over the summer during a controlled dynamometer test session, and that was after a reported decade of development, and investment in excess of half a billion U.S. dollars as of 2014.
Formula 1 engines require an army of engineers to operate and monitor, due to their complexity and sensitivity. The startup procedure alone involves bringing the engine to operating temperature before even attempting to crank it over; mechanical tolerances are so tight that the engine is literally seized when cold.
The Mercedes Formula 1 engine also reaches this efficiency level with the use of a thermal energy recapture system, dubbed the MGU-H (Motor Generator Unit, Heat) which gathers typically wasted thermal energy from the turbocharger, and converts it into electrical energy. Development and improvement of the MGU-H, however, has been so costly to Formula 1 engine suppliers that they wish to see it withdrawn, citing both the staggering investment required to optimize the device, and the lack of road relevance.
Should Hyundai intend to extract this level of efficiency from a mass-produced road car's engine, which is expected to start up on a whim, in any conditions, and operate without an MGU-H, it may need many billions of US dollars to make such an engine feasible. It may be necessary to follow in Mazda's footsteps, with their compression ignition engine, which could be one of the internal combustion engine's final evolutions in a world seeking to kill it off.
We won't discourage Hyundai for aiming at such a lofty goal. If anything, we want the Korean make to achieve this feat, and prolong the lifespan of our favorite method of propulsion: good ol' dino juice.