Many Ways, One Platform

To make road traffic more climate-friendly, there is no single key technology but a raft of innovative drive systems and energy sources. Initiated by IAV, the Berlin Powertrain Symposium brought together engineers from various disciplines.

It is a key moment: following one and half hours of intense discussion, the facilitators of a workshop hold a vote on how the market shares will compare for electric drives and combustion engines in 2030. The participants, most of them experienced development engineers, are asked to position themselves along an approx. ten-meter line between two poles. The poles stand for 100 percent combustion engine or 100 percent e-mobility. No one is standing there. But in between, nearly all positions are taken, fairly evenly, with a slight concentration in the middle. The opinions on tomorrow’s drive technology vary as much as the possible combinations in a hybrid vehicle. Increasing complexity – that would probably be the common denominator.

The most important objective of the Berlin Powertrain Symposium which, for the first time, took place at the end of 2017 at the initiative of IAV is then to find sustainable solutions for future vehicle drive technologies through dialog among experts from different disciplines. “Merely optimizing engines and transmissions is no longer sufficient”, explains conference director Matthias Kratzsch, responsible for Powertrain Systems Development at IAV. “But if we go to the next level – in other words, the entire powertrain – this raises many new questions.” How do we combine all powertrain components in the right way? How will the framework conditions and technologies develop? Which energy sources will be available in the future? What can innovative forms of work and methods do to help?

The question of the objectives in future powertrain development provided the starting point for the two-day event. Thorsten Herdan, head of department in the German Federal Ministry for Economic Affairs and Energy, presented his ministry’s long-term energy policy targets. “The most important target will be to leave fossil energy sources in the ground.” But it was not about dictating individual technologies to industry. “The discussion about banning the combustion engine is unproductive”, Herdan pointed out. But apart from the power sector, Germany should manage to use renewable energy in the transport and heating sector too.

Doing the calculations, Martin Schmied from the German Environment Agency then worked out that if the targets of the Paris climate agreement are to be reached, 2050 would see Germany left with a budget of 63 million tons of carbon-dioxide equivalent a year. But as it will probably not be possible to avoid 60 million tons from agricultural and industrial processes, there would be nothing left for the transport sector. “Long-term, all traffic must be brought down to zero”, Schmied said. “However, banning combustion engines is something we don’t think is very wise either.” Instead, the aim must be to shape the general framework conditions in a way that gets as many electric cars as possible on the road as soon as possible – by 2030, there are to be as many as twelve million. This would also significantly reduce noise levels in towns and cities and therefore help to improve the quality of life.

Stephan Stollenwerk from energy supplier Innogy presented what completely converting 44 million cars to battery-electric drives would mean. To provide sufficient reserve power at all times, 44 million cars would make it necessary to build up a generation capacity of around 1,200 gigawatts – currently, the total capacity of all power plants is only about 90 gigawatts. “But on account of long-haul transport, there will be no way round synthetic fuels anyway”, Stollenwerk says. The chemical energy sources that will be used in the transport sector were by no means certain. The City of Essen, for example, is trying out a methanol-powered fuel cell that propels an excursion boat.

The fact that the difficult search for new drive systems is worthwhile was shown by the presentation held by climate scientist Professor Dr. Anders Levermann who works at the Potsdam Institute for Climate Impact Research. “It is not about bargaining positions but about physics”, the expert explained. “If we were to extract all coal from the ground, the sea level would rise by 60 meters.” Greenhouse gas emissions would have to reach their maximum in the next ten years at the latest if the Paris targets are still to be reached. “A two-degree rise in temperature is still manageable, but the 1.5-degree target is wishful thinking.” Even then, some processes would be irreversible. The Arctic, Levermann says, will be ice-free in 2050 during summer either way.

In the panel discussion that followed, the focus was on implementation in the automotive industry. Although the fleet limit values currently discussed in Europe for 2030 were ambitious, envisaging a 30-percent reduction within ten years, they were essentially moving in the right direction. “In the short term, we can achieve something by improving energy efficiency”, Schmied confirmed. However, Levermann warned against focusing on short-term measures. Without any long-term structural change, it would not be possible to achieve a zero-carbon transport sector. A calculable minimum CO2 price was to provide the basis for this.

In around 20 expert presentations, attention turned to short-term efficiency measures, such as mild hybridization through a 48-volt vehicle electric system, as well as technologies that will only have any broad impact in the long term, such as the fuel cell. It soon became clear that there is no single path to future propulsion. “As in a puzzle, we must piece together many pieces”, Kratzsch explains. “This also includes digital technologies, like artificial intelligence. Only if we use all options will we manage have individual mobility with hardly any climate-harming emissions.”

Encourage and make a start – this was what the theme-based cafés set out to do. The unusual workshop format at the end of the first day extended an invitation to participants to reconsider or at least focus their own position in discussion with other experts, for example in respect of tomorrow’s source of energy. The facilitators asked participants to project themselves into the future and look back on the developments of the last two decades from the perspective of 2050.

This playful approach made one thing clear: the question of energy source cannot be isolated from the way vehicles are used. This is what the representative of a major manufacturer had to say: “2034 was the last time I drove a car.” At least equally as surprising: for many participants, hydrogen became an integral part in the mix of energy sources after 2030.

“Hosting the Berlin Powertrain Symposium, we have created a platform to represent this diversity”, says Kratzsch, summing up. “In addition, there was also the opportunity to engage in dialog on the challenges that face engineers.” This dialog is to be intensified in future: the second symposium is planned for 2019.