Soziale Mitte, Walldorf, Germany

The City of Walldorf’s new “Soziale Mitte” is the link between the existing city center and the newly built neighborhood Walldorf South. It consists of four buildings which house the extension for the primary school, a kindergarten, an after-school care and a gym with canteen for all generations.
The buildings have been planned and designed in accordance with the Passive House guidelines. Well-insulated, airtight façades form the base for energy-efficient operation. Central ventilation systems provide fresh air. In addition all buildings are optimized for natural ventilation and optimal daylight supply. The fresh air is preconditioned in earth ducts – it is preheated in winter and precooled in summer. Exposed thermal mass in combination with night time air flushing improve the thermal comfort during summertime. The displacement ventilation is regulated according to demand. In the majority of spaces natural cross ventilation is possible.
The buildings are minimized in heating energy and electricity demand for lighting. Photovoltaic panels on the roofs are used to generate electricity. Solar thermal collectors are utilized for the production of hot water in the gym and the kindergarten. A gas boiler covers the residual heat demand. The use of biogas is planned in order to achieve a regenerative operation of the buildings.