Photovoltaic panels reflect the sun and the stringent quadrilateral design makes the building look like a black monolith. People’s first visit to the solar house built by the Technische Universität Darmstadt is often a little disconcerting. Compared to conventional buildings, the German students’ design is rather unusual. Yet the building really can’t be that bad, because the team from Darmstadt won first prize in the Solar Decathlon 2009 competition for the most energy-efficient and attractive house – and thus successfully repeated its victory at the last Solar Decathlon in 2007. The competition for the best solar house is organized by the US Department of Energy every two years.
The houses for the Solar Decathlon were built on the National Mall in Washington D.C. not very far from the White House and then subjected to comparisons in ten different disciplines: architecture, market viability, engineering, lighting design, communications, comfort zone, hot water, appliances, home entertainment and net metering. Some disciplines were evaluated by the panel of judges, others by the scores in various tests.
The team, led by architecture professor Manfred Hegger and the only one from Germany, was able to hold its own against 19 other competitors from the US, Canada and Spain. It was followed by the University of Illinois in second place and Team California in third place. The two professors Manfred Hegger (Department of Architecture) and Thomas Hartkopf (Department of Electrical Engineering and Information Technology), eight other faculty members and 24 students spent several months planning and constructing a building that meets the highest architectural, atmospheric and energy-efficiency standards, as is clearly demonstrated by a first place in the “comfort zone” discipline, a second place for “hot water” and two third places for “architecture” and “lighting design”. The decisive factor in Team Germany’s overall victory, however, was the outstanding result in the “net metering” contest which measured the amount of energy produced over and above the house’s needs. The technological highlights of the winning house include extremely well-insulated external walls, a ventilation system with heat recovery, improved energy availability by means of a heat pump, photovoltaic panels covering the entire external surface and a one-room concept that facilitated a spacious interior design on a relatively small area.
