Vicente Guallart's proposal was selected for the design of the main building of the Expo 2012 in Wroclaw, a city in the south of Poland, near the German border. The topography of the mountain is such that its south face forms an angle to accommodate a bank of photovoltaic panels on the façade which will generate part of the energy consumed by the building.
Personally, i think we can find the embryo of Guallart's project in some of his writings.