The Double-helix of BMW-Welt in Munich from Coop Himmelb(l)au (with Tom Wiscombe, Senior Designer) is a hybrid structural/mechanical armature. Developed with GARTNER, the steel profiles are welded to create a continuous hollow network which is filled with liquids connected to heat exchangers and geothermal heat pumps. The system is reversible, cooling in the summer and heating in the winter like a giant 3-dimensional radiator.