At the EUSALP specialist conference in Bregenz on 8 May 2025, a KnowHowHP workshop tied to Work Package 2 (stakeholder engagement and case studies) was held. With 41 participants (35 from outside), interest in heat pump renovations for multi‑family housing was high.
Boosting Efficiency Through Targeted Planning
The first talk focused on room‑by‑room heat load calculations and targeted replacement of radiators. The goal is to reduce flow temperatures to around 55 °C—a key factor for efficient heat pump use in existing buildings. The discussion revealed that alternative systems like split air conditioners are considered but not yet sufficiently researched for practicality. Domestic hot water heating in central systems was also critically examined. Participants were especially interested in questions around CO₂ savings and the economic impact of system transitions.
Real‑World Cases Show Opportunities & Challenges
The second presentation featured two real renovation examples. The Friedrich‑Inhauser‑Straße project stood out, where monitoring and simulation results tightly aligned. It became clear that good planning—such as using dynamic building simulations—significantly contributes to efficiency. Discussions of bivalent systems (e.g., heat pump plus electric heating element) revealed differences between Austria and Germany in economic frameworks and system norms.
User‑Perspective Barriers
A brief participant survey showed that while many live in multi‑family houses, few live in buildings renovated with heat pumps. The biggest barrier to conversion is often the complex ownership structure. The more owners involved, the more coordination is needed—especially on issues like noise, investment cost, and efficiency.
KnowHowHP as a Solution Approach
In the closing short presentation, the KnowHowHP project was introduced. Its aim is to support planners, energy consultants, and installers through targeted training and digital tools in an integrated renovation process. A key highlight from the presenters was that heat pump sizing should never be based on old boiler capacities. Instead, a sound planning approach with tools developed by KnowHowHP is essential.
The workshop provided valuable impulses and demonstrated the strong interest and need for exchange in the field of climate‑friendly renovations—especially when it comes to practical solutions for the existing stock.