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The new type of BIPV/T systems offer architects the option to develop innovative and aesthetically pleasing designs. In Europe a recent marketing study indicated that nearly seventy percent of a sample of polled architects would consider installing PV elements in the design of new developed buildings or on existing buildings during refurbishment. Since 1990 several projects have given many opportunities for creative design and environmental innovation as photovoltaic can be applied to many parts of a building’s external skin. More than 9000 square meters of PV integration have been realized already in Europe by 1996 (Benemann and Chehab 1996; Ossenbrink and Helmke 1996)

One PV-system is integrated in the façade of an office building (floor area of 8,100m2) located in Berlin-Kreuzberg, Germany. The façade consists of granite and panels, mounted by a newly developed technique, thus creating a structural glazing façade by the use of star shaped mounting devices for both the granite and the glass panels. It generates 1689kWh of electricity with the average annual solar irradiation 596 kWh/m2. In another administration building of the municipal utility Stadtwerke Halle, architect Heitmann used PV systems in a skylight of more than 30m length which covers a hallway. Each panel consists of three parts, where one OPTISOL energy façade element with polycrystalline solar cells is mounted between two smaller insulating glass elements. Thus a sufficient lighting of the hallway with daylight is ensured for any weather. This PV system can generate 2500 kWh of electricity with the average annual solar irradiation 800 kWh/m2. Also in Germany, the science Park Gelsenkirchen has been created and has installed a 210 kWp generator which represents the largest roof-top power station worldwide by that time. This PV system is contributing 190,000 kWh of electricity with the average annual irradiation of 800 kWh/m2 (Benemann and Chehab 1996).