Green Building in Germany

Seen from the outside, surPLUShome is a shiny black glass cube. Inside, on a floor area of 80 m2, the dominant features are light, wood and clear lines. The technical and electrical systems are perfectly integrated into the design, and on balance the building produces about twice as much energy as it uses.

The house, designed and built by students at the Technical University of Darmstadt, was the great success at an international competition for solar construction: Team Germany won the Solar Decathlon 2009, an international competition for universities hosted by the U.S. Department of Energy, which takes place every two years.



20 teams from the USA, Canada, Puerto Rico and Spain had qualified for the competition alongside the team from Darmstadt. The task was to design a house operated by solar energy alone, to build it in Washington and to face the competition in a total of ten disciplines including architecture, lighting design, the comfort zone, market viability and net energy produced or consumed. In specific terms that meant that the total energy needs of a two-person household had to be produced using solar energy alone. All the functions such as doing the laundry, cooking and using warm water were actually carried out, and all the household appliances and home entertainment tested. The air temperature and humidity had to satisfy precisely defined values.

A fine balance

The winning house from Darmstadt gained points with its fine balance of energy saving, energy efficiency and solar energy production. The building envelope, in passive house quality, kept energy losses to a minimum and ensured a high level of comfort, while the photovoltaic elements integrated into the roof and walls provided the required energy. The façade was particularly impressive, featuring a system using photovoltaic tiles made of dark glass modules developed by the students themselves, which also gave the house its characteristic appearance.



A team from Darmstadt had already won the Solar Decathlon back in 2007. The 2009 victory was thus a successful defence of the university’s title. “With a new house and a new team, of course,“ says architecture student Sardika Meyer, who concentrated on the design of the outdoor areas around the surPLUShome. It took around one and a half years to develop the winning house of 2009, and involved close cooperation between the departments of architecture and electrical engineering at the Technical University of Darmstadt. In Sardika Meyer’s view, it is natural for work to be interdisciplinary. “There is no other way to do it if you want to build sustainably,“ says the 24-year-old. Construction engineers, lighting technicians, materials scientists and sociologists were also involved in the project. Says Sardika Meyer: “We showed how energy and solar aspects can be brought into harmony with high architectural and aesthetic requirements.“

“Prototype Home 2015”

These qualities could make the winning house a milestone in energy-efficient construction, if you go along with Werner Sobek’s assessment, at least. Ecohouses have hitherto been a commercial flop partly because aesthetically, they are depressively austere, believes architect, engineer and President of the German Sustainable Building Council. The key is to make ecology “breathtakingly attractive and exciting,“ said Sobek in a presentation on sustainable planning and construction.

But it is not only beauty that counts. The (construction) costs also play a decisive role for the market viability of solar houses. The surPLUShome was created as a prototype called “Home 2015“ for approximately € 450,000. The Federal Ministry of Transport, Building and Urban Development supported the high-tech project, as did sponsors from the construction industry. It is now the task of young architects like Sardika Meyer to further develop prototypes of this kind in interdisciplinary cooperations. How successfully future-orientated approaches to construction are applied to everyday life will depend partly on the quality of university training. Johanna Henrich of the University of Darmstadt is a graduate engineer who supervised the Solar Decathlon project. Regarding the current teaching situation, she says, “There are many post-graduate courses in the field of energy efficiency, but they are not usually offered in combination with architecture.” That is different at the Technical University of Darmstadt: “Our Design and Energy-Efficient Construction Programme makes us a pioneer in this field. We are delighted about our success at the Solar Decathlon in Washington.“

The Solar Decathlon is now catching on in Europe, too. In July 2010, the first Solar Decathlon Europe will be taking place in Madrid. The Federal Minister of Economics and Technology is supporting the participation of teams of students from Berlin, Rosenheim, Stuttgart and Wuppertal.