"Wilhelma" Elefantenwelt, Stuttgart, Germany

The botanical garden and Zoo "Wilhelma" in Stuttgart is realigning and modernizing itself at the same time. The crowning project for the emerging Asian complex is „Elefantenwelt“, (Elephant World), a new building with a large outdoor area. The existing building is already more than 40 years old and will be replaced by a modern building that allows for contemporary keeping: a wooden shell construction with a span of 100m / 330 feet, with large outdoor facilities offering enough space for a herd of Indian elephants.
However, this facility can only be built after completion of the Rosenstein Tunnel, which passes under Rosenstein Park and Wilhelma. In the inner shell of the tunnel, similar to underfloor heating systems, pipes are laid which lead to heat exchangers. The system absorbs the waste heat from the tunnel operating equipment and from car traffic, as well as the heat in the ground, and transfers it to the transferring fluid in winter. A heat pump raises the temperature to a usable level and puts this heat to use at Wilhelma. In summer, when cooling is needed, thermal energy can be dissipated into the ground. It is expected that 200 tons of carbon dioxide less will be released into the environment every year than with a conventional heating system, i.e. considerably fewer emissions.
A large part of the heating energy is fed into the room via radiant heating. For this purpose, traffic areas and walls are heated slightly to ensure the necessary comfort for visitors, animal keepers and, last but not least, elephants. The entire hall can be ventilated in a natural way. Optimized for daylight conditions, façade and roof ensure that sufficient light also enters for plant growth and that Wilhelma's botanical requirements are so fulfilled. The wood of the supporting structure is a lifelong CO2 sink and a PV system integrated into the roof is a further contribution to reducing CO2 emissions during operation.