Expert insights and lively discussions on heat pump technology

The most recent Energy Talk on April 16, 2025 was met with great interest: Around 50 citizens from the region took the opportunity to find out first-hand about heat pump technology. The campus was delighted with the high level of participation and the lively interest in professional discussions.

The event was led by coordinator Dr. Gerd Hofmann and Dipl.-Ing. Oliver Abel, laboratory engineer at the Feuchtwangen campus. Together, they presented a practical and easy-to-understand lecture on both the physical principles and current developments in heat pump technology.

The event kicked off with a keynote speech. “We want to make the technology behind the heat pump understandable,” explained Gerd Hofmann at the beginning. To achieve this goal, he illustrated the principle of the heat pump using simple everyday objects such as a classic air pump and a commercially available deodorant spray. “Compression and expansion of gases lead to temperature changes – that is the physical core of heat pump technology,” said the campus coordinator.

Oliver Abel supplemented the presentation with demonstrations on the laboratory’s test stands. There was a particular focus on the use of environmentally friendly refrigerants: while fluorinated refrigerants (HFCs), which are harmful to the climate, are still frequently used, natural alternatives such as butane, propane or propene are increasingly moving into the foreground. “These substances have a significantly lower impact on the environment and are also highly efficient in operation,” emphasized the employee. He also pointed out that the refrigerant used also has an impact on the operation and maintenance of the systems: “With climate-damaging refrigerants, the prescribed inspection intervals are significantly shorter – which means more effort and higher running costs.”

At the end of the presentation, the speakers gave an outlook on the magnetocaloric heat pump – an innovative technology that works without refrigerants. “These systems use a magnetic field to cause temperature changes. This is emission-free, low-maintenance and has great potential,” explained Gerd Hofmann. However, such devices are currently still in the development phase.

Numerous practical aspects were discussed in the subsequent Q&A session. The participants learned about day and night setback in heating systems, the differences between devices from different manufacturers and the question of which heat pump is suitable for which type of house. The role and costs of energy consultants were also discussed. “Sound energy advice before a retrofit is not an option, but a real recommendation,” emphasized both speakers.

Other points of discussion included the correct dimensioning of buffer storage tanks, the challenges of using heat pumps in larger apartment buildings and the average service life of the systems. The guests took the opportunity to engage in a direct exchange with Campus experts, energy consultants and practitioners.

With the successful combination of technical input, illustrative practical examples and open discussion, the Energy Talk at the Feuchtwangen campus once again proved to be an important platform for knowledge transfer and dialog. The direct exchange between research, consulting and the public is a central building block on the way to a climate-friendly energy future.