IMO, All the major Automobile Manufacturers are looking at the new power units F1 is using this year. F1 is already over 40% thermal efficiency and still in their infancy. All the major turbo company's are now testing the next generation electric assist / generator turbo.
Here's a quote from Professor Dr Thomas Weber, the Daimler board member responsible for research and development in F1.
"The key challenge for the future is fuel economy and efficiency and, with the change in regulations, F1 is the spearhead for development," Weber said.
He said it had become "hard to explain" why F1 was using the old V8 engines.
The sport switched this year to 1.6-litre turbo hybrid engines, replacing naturally aspirated V8s. Mercedes have dominated so far, with Lewis Hamilton winning two of the first three races and team-mate Nico Rosberg the other.
Efficiency is at the heart of the new F1, with a limited fuel allowance and a maximum fuel-flow rate.
"Now with these new regulations I can clearly convince the supervisory board that the [F1 team] are doing exactly what we need - downsizing, direct injection, lightweight construction, fuel efficiency on the highest possible level, new technologies and combining a combustion engine with an e-motor hybrid."
He said technology transfer to road cars from the new F1 engines, with their dual energy recovery systems, was already happening and he hailed the "incredible" achievement of all the engine designers in F1.
The new F1 engines have a thermal efficiency of "40% and above" - better than that of a road-going diesel.
"Never before did we do such a huge step forward in such a small space of time from a V8 naturally aspirated engine to downsizing, turbocharged, all the technologies with one step," Weber said.
"It was the biggest challenge ever."
BBC Sport - Formula 1: Mercedes could have quit over engines