Summary:
This study investigates the potential of energy sufficiency measures in public buildings in Lausanne, focusing on behavioral and technical optimizations. A three-level methodology was implemented: (1) theoretical analysis across 350 buildings, (2) in-depth assessment of 20 representative buildings, and (3) participatory workshops and in-situ measurements in 3 selected buildings. Findings highlight the significant energy savings potential in mechanical ventilation and heating systems. On-site CO2 and energy monitoring validated occupant complaints and revealed system malfunctions. The workshops demonstrated that engaging building users in energy sufficiency initiatives requires careful participant selection and structured facilitation. Initial results suggest that energy sufficiency strategies can achieve substantial energy reductions, particularly in small to medium-sized buildings with a single function. A holistic approach combining technical data, user involvement, and behavioral changes is recommended. Future work will refine quantification tools and best practices for scaling energy sufficiency in public buildings.