The photovoltaics industry is booming – more and more solar modules are appearing on rooftops, and even large-scale solar power plants are increasingly feeding power into the grid. Multi-junction solar cells are particularly efficient in this regard: they can achieve efficiencies of up to 43 percent - twice the level of conventional solar cells made of crystalline silicon.
The trick: they consist of several semi-conductor layers that combine to transform the entire spectrum of sunlight into electrical energy. This technology is used in concentrator photovoltaics. There, lenses focus the light of the sun 500 times onto tiny solar cells. These concentrator systems produce solar electricity on a large scale, particularly in solar power plants located in areas rich in sunlight. Among the producers of these plants is SOITEC Solar GmbH, in Freiburg, Germany, a former spinoff of the Fraunhofer Institute or Solar Energy Systems ISE.
The multi-junction solar cells themselves consist of some 30 semi-conductor layers built up, layer for layer, on ultra-pure crystals of germanium or gallium arsenide. These materials are very costly, however. In a joint Franco-German project, researchers at ISE in Freiburg and their colleagues from the Carnot-Institut Laboratoire d‘électronique des technologies de l‘information CEA-LETI in Grenoble, France, are working to develop new substrates for multi-junction solar cells. The new technology replaces the expensive materials with reusable substrates. Whereas up until now the solar cells had to remain in place atop the germanium or gallium arsenide crystals, the solar cells are now removable from the new substrate which is recycled several times. This way, the cost of producing solar cells can be reduced by up to 20 percent.
„In the Solar-Bond project, two high-tech institutes have combined their skills,“ according to Dr. Frank Dimroth, Head of Department III-V - Epitaxy and Solar Cells at Fraunhofer ISE. „CEA-LETI is a leader in the microelectronics field and Fraunhofer ISE in photovoltaics.“ The French colleagues develop the substrate and adapt its properties to the requirements involved in growing multi-junction solar cells; the German scientists then apply the solar cells to these substrates and process them to create ready-to-use devices. The researchers are also working closely with SOITEC, a French company: in the future, the new solar cells will be used in their concentrator modules.
The scientists were honored for their international research on December 5, 2011, in Paris with the Franco-German Business Award 2011, presented by the Franco-German Chamber of Commerce and Industry AHK. The business award is presented in recognition of best practices over the past two years. Patrons of the award are the French Minister of Economy, Finance and Industry, François Baroin; and the German Federal Minister for Economics and Technology, Dr. Philipp Rösler.
SOLARBOND is one of 26 projects sponsored under the Inter Carnot Fraunhofer program (http://www.programme.inter.carnot.fraunhofer.org). The purpose of this program jointly run by the German Federal Ministry for Education and Research, Fraunhofer and The French National Research Agency is to establish strategic partnerships between French and German research and industrial organizations.
Karin Schneider | Fraunhofer-Institut
Muscle Growth in the Computer: International Team Wants to Unravel the Formation of Myofibrils
13.06.2018 | Technische Universität Dresden
Innovation Award of the United Nations Environment Programme for PhD Student from ZMT
22.03.2018 | Leibniz-Zentrum für Marine Tropenforschung (ZMT)
In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.
Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...
Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...
Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.
Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...
The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.
Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.
An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.
Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...
13.06.2018 | Event News
08.06.2018 | Event News
05.06.2018 | Event News
22.06.2018 | Materials Sciences
22.06.2018 | Earth Sciences
22.06.2018 | Life Sciences