Leibnitz-Institute IFL, Leipzig, Germany

Leibnitz-Institute IFL

The new building of the Leibniz Institute of Regional Geography (IFL) is the first to be constructed on a large site at Wilhelm-Leuschner-Platz on Leipzig's inner city ring road. The climate and energy concept developed together with the architects is based on a holistic approach in order to offer the best possible comfort with the least possible technical effort at the lowest possible energy consumption.

The natural ventilation in the offices is supplemented by decentralized mechanical ventilation units for the winter. With low technology and energy input, energy and heating power are saved thanks to heat recovery and a draught-free indoor climate is ensured. In summer, the thermal mass of the open concrete ceilings is used: Night ventilation via naturally driven cross-ventilation through the atrium enables passive cooling at night. Specially developed lamella systems in front of the façade opening wings protect from weather and burglary.

The concept for the atrium roof also follows the passive approach: a micro sun protection louver integrated into the roof glazing prevents direct solar radiation from heating up too much. However, it is permeable for diffuse radiation, which is low in energy but important for lighting; a high quality of daylight is achieved. Mechanical sun protection can thus be dispensed, and the daylight always finds its way into the atrium.

In the archive areas, a principle called Zephyr serves as a model in which a dense, solid shell allows as little climatic disturbance as possible from the outside. In order to maintain a robust and stable indoor climate, an airtight and windowless concept is implemented, which buffers fluctuations in the indoor climate by means of high thermal and humidity regulating storage masses. Thermal and hygric deficits can thus be compensated continuously and efficiently. Thus, the technical systems required to meet the climatic boundary conditions can be reduced to minimum.

Heat is supplied by a heat pump via geothermal probes, with district heating during peak loads as backup. Thanks to its reversibility the geothermal system can be used for free cooling in summer, if required. A photovoltaic system on the roof of the building locally generates renewable electricity.