Interview with Markus Leitner, GG Group
“Active cooling becomes relevant when thermal limits constrain performance”
Markus Leitner studied mechanical and automotive engineering at the TGM in Vienna.
Markus Leitner
Rising power demand is forcing the wire harness industry to rethink weight, packaging and thermal limits. Markus Leitner, Director Group Product Management & Business Development at GG Group, explains why system-level integration and active cooling are moving into focus.
Higher electrical loads, tighter packaging constraints and increasing system complexity are changing the requirements for automotive wiring systems. Markus Leitner, Director Group Product Management & Business Development at GG Group, has worked at the company for more than two decades, including in key account management, e-mobility business development and global sales.
At the Automotive Wire Harness & EDS Conference Detroit 2026, he will join Dilan Jordan of Amphenol Tuchel Electronics and Mike Riley of Voss Automotive for the presentation “Liquid Cooled High Voltage Harness Systems – Game Changer for Modern Vehicle Architectures”. Ahead of the event, Leitner explains how electrical, thermal and mechanical requirements are converging and where active liquid cooling could become relevant.
Looking ahead five years, what will be the single biggest challenge for the wire harness and EDS industry in North America, and why?
The key challenge will be meeting rising power requirements while maintaining affordability, scalability and sustainability. As vehicle architectures become more electrified and software-driven, customers still expect shorter charging times, higher efficiency and competitive vehicle costs. The industry must therefore deliver greater electrical performance without proportionally increasing weight, packaging space, material use or system complexity. Success will depend less on optimising individual components and more on integrating electrical, thermal and mechanical systems efficiently within a scalable vehicle architecture.
Where do you see the biggest gap between what next-generation E/E architectures require and what today’s development and manufacturing ecosystem can actually deliver at scale?
The main gap is probably not technology, but integration. Next-generation architectures require power distribution, thermal management, software, diagnostics and manufacturing processes to be engineered as one system. Today’s ecosystem, however, is still largely organised around component-based responsibilities and supply chains. Closing this gap requires earlier cross-disciplinary collaboration and system-level optimisation instead of local component optimisation. We believe that future high-performance architectures will increasingly benefit from cross-domain engineering approaches. Power2Flow demonstrates how wiring systems, connector technology and fluid management can be combined to solve challenges at system level.
At system level, where is the break-even point at which active liquid cooling becomes more attractive than increasing conductor cross-section, raising system voltage further or accepting a lower continuous current?
From our perspective, there is no single break-even point that applies to every application. It depends on the vehicle architecture, performance targets, duty cycle, packaging constraints and total system cost. Active cooling becomes relevant when thermal limits constrain performance or drive disproportionate increases in weight, packaging space or complexity. Whether active cooling, larger conductors, higher voltage levels or different operating strategies provide the best solution depends on the individual use case.
How do you design the electrical and coolant paths so that a leak, blockage, pump failure, pressure loss or crash event cannot turn into a high-voltage safety failure?
Safety requires a layered engineering approach, not a single protective measure. Foreseeable faults must be detected, managed and mitigated before they become safety-relevant. This typically combines physical separation, robust component design, diagnostics, fault monitoring and defined system responses under abnormal operating conditions. Ultimately, safety is demonstrated through a structured validation process and compliance with applicable industry requirements rather than through any individual design feature.
Which parameters dominate the thermal-hydraulic optimisation of a cooled HV harness: conductor material, conductor geometry, contact resistance, coolant flow, pressure drop, ambient conditions or the charging duty cycle?
Electrical, thermal and hydraulic performance are tightly coupled, with conductor design, interfaces, heat transfer, coolant characteristics, operating profiles and environmental conditions all affecting the final result. So basically, no single parameter dominates in isolation. This is precisely why we believe a system-level perspective is essential. In projects such as Power2Flow, the objective is not to optimise an individual parameter, but to optimise the overall balance between performance, efficiency, packaging space, reliability and cost.
How do you validate the lifetime of a component that combines a high-current electrical path and an active fluid circuit, and which coupled electrical, thermal, pressure and vibration tests reveal problems that separate qualification tests would miss?
Lifetime validation is critical for technologies that combine multiple physical domains. A component integrating high-current transmission and thermal management must be tested under realistic operating conditions that reproduce the interaction of electrical, thermal and mechanical loads over time. In our view, the key question is not whether each individual subsystem functions well in isolation, but whether the overall system maintains its intended functionality throughout the entire life cycle. For concepts such as Power2Flow, this means that validation has to consider the interaction of all relevant influences rather than treating electrical and thermal aspects as completely separate topics.
Finally, what do you personally hope to take away from the Automotive Wire Harness & EDS Conference Detroit 2026?
We hope to leave the conference with new insights and perspectives as well as good questions. As the automotive industry is going through a period of significant change, the value of this conference lies in open discussion of the associated challenges, opportunities and emerging trends. These exchanges are often as valuable as the presentations themselves.
