In Support of Diesel’s Future

September 1, 2018

Dr. Stefan Pischinger: “The hybridized combustion engine can deliver zero CO2 emissions on a well-to-wheels basis.”

Earlier this year a group of German engineering professors created a stir in Europe by co-authoring a paper stating their support for the diesel engine. One of the authors was Dr. Ing. Stefan Pischinger, co-founder and CEO of global engineering consultancy FEV Group. Widely respected as a leading expert on combustion engines and propulsion systems, Dr. Pischinger serves as Professor and Director of the Institute of Combustion Engines RWTH Aachen, Germany. He is also a member of the supervisory board at Mahle GmbH. Dr. Pischinger spoke with Editor-in-Chief Lindsay Brooke in Detroit.

Your paper presented a bold “reality check” on diesel — that it still has an important role to play in the world’s transportation system.

The paper was targeted at the very emotional discussion about diesel engines in Germany today. Forty professors in the technical community published this paper. No industry was involved. The goal was to de-emotionalize the discussion and to say the diesel emission ‘problem’ is technically solvable. The group said that what happened in the so-called ‘dieselgate’ was a really bad thing — but it had nothing to do with the engine itself!

We should only look forward. The global emission test cycles have been changed. Our clear vision is that the diesel can fulfill all the emission standards in the future. And it can contribute to CO2 reduction in a great way. The increase in gasoline vehicles, particularly larger ones like SUVs, will only increase CO2 emissions.

I agree with what John Heywood [MIT Professor Emeritus] says about the ICE living well into 2050. We have this minus-60% GHG [greenhouse gas] scenario for Europe and we still have a considerable number of combustion-engine-driven cars that are hybridized. So, we will not see the combustion engine disappear. FEV’s market analysis for 2030 predicts 20% of vehicles in Europe being pure electric; in China maybe close to 30%. In the U.S., we see the total of EVs below 10%.

Can people who have turned away from diesel be convinced they should return?

It depends where they are in the world. In Germany, diesel’s popularity has declined a lot due to the unpredictable legislations. People wonder about their car holding its value, and whether they can drive into the city anymore. I believe they can be brought back because of the great potential to further improve the technology—particularly for larger vehicles and trucks.

Engineers are continuing to make the ICE more efficient.

Certainly! We’ll be hitting 50% brake thermal efficiency (BTE) with gasoline engines. We’re at 55% with larger diesels. Some researchers are saying we can get to 60% BTE with gasoline engines.

What is the status of FEV’s range extender project?

We did not see a lot of interest for a while, but now we have several projects. We had a rotary engine range extender and also a vibration-free 2-cylinder engine in development. In a range extender the perception has to be you’re driving a pure electric car. It has to be vibration and noise free. Two years ago we built up a fuel-cell range extender. The fuel cell scales with power output. So it’s good to combine a small battery with a small fuel cell. Our vehicle has a 30-kW fuel cell but you have the battery if you need higher power.

The future will offer many different propulsion choices?

Yes, that’s our prediction. Diesel, gasoline, plug-in hybrids, fuel cells, 48-volt mild hybrids. It will depend on the application. In Europe we are shifting to renewable electricity and we believe the hybridized combustion engine can deliver zero CO2 emissions on a well-to-wheels basis, using renewable electricity combined with biomass or ‘e-fuels.’ There is much research ongoing in this area; it can provide infinite sustainable fuels for ICEs.

Electric vehicles will come. But look at China, the strongest market, where EVs are being pushed by legislation. Without that legislation, EVs would not be on the rise. The technology is still more expensive and delivers less customer benefit.

In FEV’s prognosis for 2025, a city electric vehicle with 120 miles range could be price competitive with a DI gasoline engine equipped with a 48-volt hybrid system. So, costs for EVs will come down and their competitiveness will increase.