The energy efficiency of buildings plays a central role for the energy transformation: More than 40 % of the end energy demand in Germany is caused by the building sector. To achieve climate-friendly building operation, we must reduce the energy demand and then meet it with renewable energy sources to the greatest extent possible. The research work of Fraunhofer ISE addresses nearly all phases in the life of a building – from planning through construction to operation. 

We work on reducing the demand for space heating and space cooling with optimized building envelopes and by integrating renewable energy sources. New glazing technology, appropriate controls for solar-shading systems and colored glass covers for building-integrated photovoltaics offer diverse options to architects. Examples can be found in a database with extensive data and tools to construct nearly-zero energy buildings. 

For supplying heat to buildings, we concentrate mainly on heat pumps. Our work on this technology addresses the entire value chain: from component development for the cooling circuit, through equipment and systems development, to quality assurance in practical operation. Funded by the German Federal Ministry for Economic Affairs and Energy (BMWi) and involving a broad industrial consortium, we began with the development of a compact propane cooling circuit in October, 2020. 

The digitalization of processes is also an important component to increase energy efficiency and promote sector integration. Planning with digital methods such as Building Information Modelling (BIM) helps to preserve the information flow over the life cycle of a building with a consistent semantic description. Product data form an important part of these data-based processes. In July 2020, we became the European Regional Data Aggregator for the National Fenestration Rating Council NFRC and contact for European glazing manufacturers who address the North American market with their products.