For several years now, the chair at the IFS, under the leadership of Prof. Michael Bargende, has been moving away from the traditional combustion engine toward broad-based research on different types of powertrain systems. The focus is on the systemic optimization of all types of powertrain systems: from hybrid, fuel cell, and electric drives to combustion engines that use CO2-neutral fuels. The renaming of the chair to “Automotive Powertrain Systems” does justice to this change.
Different types of powertrains – there are many opinions on this. It’s a competitive field, which often makes it difficult to have an objective discussion about it.Prof. André Casal Kulzer
When developing powertrain systems, Prof. André Casal Kulzer relies on diversity. He studied mechanical engineering at the Technical University of Lisbon, Portugal. After studies abroad with the Erasmus program at the Technical University of Braunschweig, he did his doctoral degree studies at the University of Stuttgart. He was one of Prof. Michael Bargende’s first doctoral researchers. Dealing with engines and drive technology is in the blood of the 46-year-old. On his father’s side, he comes from the Bavarian engine manufacturer family Kulzer. His mother is the daughter and niece of the founders of the company Metalurgia Casal, the then largest motorcycle manufacturer in Portugal. His Bavarian father was one of the former Zündapp engineers who were sent to Portugal in order to share their know-how. That’s how his parents met each other.
With Kulzer, the university gains a dedicated engine developer not only because of his family background. Due to his many years of work in the research and development of drive systems at the companies Bosch and Porsche, he also brings with him a lot of experience and a large network of worldwide contacts.
Many options to choose from
André Casal Kulzer is not only interested in drive systems, and he takes the subject even further. He also reflects on mobility in general and on how we can realize it in a way that is environmentally friendly and socially just. The powertrain developer is aware that there is a lot of emotion in this issue: “Mobility concerns us all, it has a strong social component, and self-fulfillment and a sense of freedom are also part of it.” According to Kulzer, it would be a bad idea to put all eggs in one basket when developing mobility solutions for the future, because there are various options to choose from in terms of energy storage. Which are, for example: Drive systems based on chemical battery storage, hydrogen, and renewable fuels. These drive pure or hybrid powertrain systems based on electric motors, fuel cells, and internal combustion engines.
It is important to look at the entire life cycle of a vehicle, he says. For the development of an environmentally friendly system, all relevant aspects need to be taken into account - from resource extraction and production to energy sources and energy storage, to energy conversion. “We need to monitor, comprehensively analyze, and compare the various drive systems throughout the entire cycle. For each application, there are several possible solutions.”
André Casal Kulzer considers the research on electrification and the further development of electric drive systems the main focus of his work. In this context, the degree of electrification is also important. In plug-in hybrids, for example, small low-weight batteries are being used. These last for a driving distance of more than 50 kilometers and weigh only about 1/10 as much as batteries in vehicles whose drive system consists of batteries entirely. It is therefore important to consider what a vehicle is to be used for, and whether to achieve the reduction of CO2 emissions by reducing weight and using rare earths, or by means of a largely CO2-neutral drive system that works with the right mix of green power and/or green fuel.
Another important subject of the chair’s research is the substitution of fossil fuels with renewable, biogenic, or synthetic - and therefore “green” - fuels. Synthetic fuels are made with carbon previously extracted from the air. If the subsequent production process takes place exclusively with the use of regeneratively generated energy, the fuel is climate-neutral, because the amount of CO2 released during its combustion is only as large as the amount of CO2 previously extracted from the air. In this way, a CO2-neutral cycle is created. Hydrogen from renewable electricity, methanol, and syngas are other starting materials with which fuels can be synthesized. Sewage sludge, used cooking oil, and waste grease can be processed into biogenic fuels.
Kulzer and his team study individual powertrain systems and compare the results. “We’re performing a benchmarking study on energy efficiency and CO2 neutrality. Artificial Intelligence, too, helps us to find out which operating strategy is the right one for which vehicle or mobility requirements.” And to top it all, the research is not limited to cars. “We also want to include e-bikes and motorcycles and expand the research area to motorsport applications,” Kulzer explains.
Research on acoustics should also not be forgotten: In this field, the institute has great expertise. The aim is to eliminate annoying noise, but at the same time it’s important that an electric vehicle can be heard. Therefore, the scientists have to design a noise. In addition, many people associate the noise of an engine with emotions, like in motorsport.
So Kulzer and his team won’t be bored anytime soon. He says about himself: “I’ve always been research-savvy.” During his time at Bosch and Porsche, a large part of his work consisted of research-intensive activities, and his responsibilities also included the supervision of doctoral researchers on the industrial side.
Passing the baton in the best possible way
The Institute of Automotive Engineering at the University of Stuttgart is working in close cooperation with the Research Institute for Automotive Engineering and Powertrain Systems Stuttgart (FKFS). Here, too, the scientist will follow in the footsteps of Prof. Michael Bargende. As of October, he will take over the leadership of the Automotive Powertrain Systems board division, of which he is currently the deputy head. Regarding this activity, Kulzer says: “I like that there is also a certain entrepreneurship associated with my job at the FKFS. That’s another way I’m carrying on the family tradition.”
André Casal Kulzer is living near Stuttgart with his Portuguese wife and three daughters. He is very pleased to return to the University of Stuttgart and to take over the chair of his former doctorate supervisor: “I’m very grateful to the appointments committee and to the university management for giving me nine months to work with Prof. Michael Bargende and accompany him. There is no better way to pass the baton.”