Sustainable modernization concepts with energy management system for existing residential districts – synergies of a cross-technology and cross-building approach

The EU and its member states have recognized that reducing CO2 emissions in buildings is a decisive task for achieving climate protection targets. With regard to Germany, only moderate progress is discernible, which is primarily reflected in low modernization rates and modernization concepts that ultimately miss their goals.A reason for this is that heat pumps, identified in many studies as the preferred and state-of-the-art heating technology, requires extensive modernization measures in existing buildings. This results in existing building owners usually opting for modernization variants that involve lower investment costs, which do not bring the necessary CO2 savings. But since these modernization concepts do not lead to the achievement of climate protection goals, repeated construction measures on the building become necessary, which exceed the previously saved investment costs. Therefore, more ambitious modernization concepts tend to be more cost-effective in the long term. The project ModEMS4Q, funded by the German Federal Ministry for Economic Affairs and Climate Protection, aims to improve economic feasibility of target-oriented modernization by generating synergies of a cross-technology and cross-building approach.ModEMS4Q looks at three distinct residential districts with single-family houses and multi-family houses which, due to their different building types and years of construction, each offer different conditions for concept development. An energy management system is central part of the modernization concepts and allows coupling with other consumers such as e-mobility. In addition to variations in the modernization of the building's thermal envelope, various supply concepts for the building's technical equipment are being considered, and the economic feasibility is being assessed. Key points of the concepts are the utilization of the local potential for renewables, the possibility for modular expansion of the concept to adjacent buildings and neighborhoods, and long-term climate neutrality.Depending on the local conditions, combinations of two concepts for the modernization of the thermal envelope, four variants for the heat supply and two financing models including potential expansion possibilities are examined and measured against reference concepts for each residential district.