Solar Energy Use in Freiburg, Germany

As the need for sustainable technologies increases, Freiburg, Germany is
emerging as an important city that greatly contributes to solar research and development.

Germany’s policy programs are designed to increase demand for solar
technologies. Consequently, there will be lower production costs and an increase the price effectiveness of solar energy. In order to encourage the adoption of solar technology, Germany has passed a law rewarding those using renewable energy sources. The Renewable Energy Law requires power companies to pay a specified price per kWh produced at the peak rate, guaranteed for twenty years, to individuals who have installed PV’s on their own private buildings. On average, the payback period to recuperate one’s initial investment is ten years. After this period, all energy generated by the solar array can be considered profit. This program has proved successful as demonstrated by the prevalence of solar technology in Vauban, a small neighborhood in Southern Germany.

Vaauban is a new innovative neighborhood that has demonstrated significant solar technology. With more than 1800 hours of sunshine each year Freiburg has an annual radiation intensity of 1117 kilowatts per square meter, it is one of the sunniest cities in Germany. The pilot building for this innovative neighborhood was the Heliotrope, a rotating solar tree house which follows the movements of the sun. Vauban quickly expanded as architects from all over the world exhibited their most cutting edge building designs that incorporated highly efficient and aesthetically integrated solar technologies. Solar arrays are not only installed on residential homes, but also form a long sound barrier to shield the noise from the adjacent freeway.

The experimental community demonstrates the benefits of solar energy in terms of climate protection, economy, and urban development and continues to inspire the next generation of architects, engineers, planners, designers, students, and citizens.

As a class we visited the Fraunhofer Institute for Solar Energy Systems (ISE) in Freiburg, Germany. It has been instrumental to the development of solar technology. On our class tour of the institute on July 28th, 2009, the hallway was lined with numerous solar technology inventions. For example, a press statement was released recently announcing a 99% efficient inverter.

Other ISE innovations draw their inspiration from nature. A solar hot water heater piping system is modeled after human blood vessels, which have the most efficient heat transfer. In addition, the institute has developed an anti-reflective material that imitates the light intensity mechanism in a moth’s eyes.