Over the early part of June, Germany set three records for solar energy production including: Over 50 percent of total demand was met with solar for the first time; a new solar Peak Power production record set; and the Weekly Total solar power output hit an all-time high. The latest analysis from the Fraunhofer ISE solar energy research institute shows that photovoltaic systems generated a record 24.24 GW between 1 and 2 pm on Friday, June 6 and a total of 1.26 TWh over the entire week. On June 9, which was a national holiday in Germany, solar power production peaked at 23.1 GW, which equaled 50.6 percent of total electricity demand, setting another milestone. As a result of these developments, and continuing activities such as the FabriGen project described below, sales of solar power storage systems are expected to skyrocket in Germany.
“German solar demonstrated just what it is capable of in the first two weeks of June,” says Tobias Rothacher, expert for renewable energies at Germany Trade & Invest, the country’s economic development agency. “The large amounts of solar electricity being generated demonstrate clearly that Germany will need more energy storage capacity in the future. Already, the more than 1.4 million photovoltaic systems are producing a surplus, especially on sunny days around midday,” Rothacher says.
“From now on, every new solar system that is installed in Germany increases the need for electricity storage solutions. The cost of storage systems is forecast to drop in the coming years and this means that storage is not only becoming more necessary – it is becoming more attractive from a financial point of view as well,” Rothacher concluded.
A solar module, six meters long and 50 cm wide, consisting of flexible organic solar cells is the result of the European research project FabriGen (fabric structures for solar power generation) Project, a joint-effort between six partners from four different countries. The module is manufactured exclusively with a roll-to-roll process. The organic solar cells do not contain the customary indium-tin-oxide and therefore have the potential to be particularly economical. The project idea targeted applications in the field of membrane architecture, which incorporates tensile membrane structures as roofs, for example, in the architectural design. FabriGen is an EU-sponsored project. Its project partners from Germany, Great Britain, the Czech Republic and Bulgaria had the mutual goal of developing fabric structures which are integrated with organic solar cells.
The project was initiated by Robert Carpenter, Managing Director of Inside2Outside Ltd. (I2O), a medium-sized company in Great Britain. For his special fabric structures with organic solar cells, he has a variety of different uses in mind, especially in the field of architecture. Applications include shading systems for pedestrian zones and bus stops as well as shed and carport roofs. The focus lies in cost-effectively covering large areas with flexible polymer constructions which cost markedly less than glass. By making use of complex structures through membrane design, the area in question can be made as large as possible, thus maximizing the solar gain. At the same time, transport and installation costs are kept low due to the light weight of the structure.
"We are pleased to have produced this successful prototype with our partners within the short time span of six months," says Dr. Birger Zimmermann, Team Leader of Production Technology for Organic Solar Cells at Fraunhofer ISE. "Manufacturing the textile structure equipped with organic photovoltaic modules was a real joint effort," remembers the project coordinator Robert Carpenter, I2O. "From vacuum processing the metal electrode at CPI, followed by coating the organic semiconductor at Fraunhofer ISE through to printing the silver contacts and the lamination at Coatema and lastly the high frequency welding of the solar foil on the fabric membrane at I2O, a range of expertise was involved."
The solar cell structure and the module design were developed at Fraunhofer ISE. The Freiburg researchers were also involved in the encapsulation development under the leadership of CPI in Great Britain. All project partners contributed their input to integrating the photovoltaics into a fabric membrane, above all, CPI and the project coordinator Inside2Outside. Coatema Coating Machinery GmbH was responsible for the process development of the large area lamination.