Press Releases 2018

Minimizing the water consumption of Solar Thermal Power (CSP) plants is an important issue, as this kind of solar power generation is often found in arid areas where the solar irradiation is high. Since these regions are also dusty, the associated yield reduction due to local dust deposition and the costs of cleaning are relevant factors. Particularly in regions lacking water, innovative water saving solutions for cooling and mirror cleaning are needed to significantly reduce the water consumption of solar thermal power plants. Any conflict of water use should be avoided to allow high acceptance of the technology. In the MinWaterCSP project, the Fraunhofer Institute for Solar Energy Systems ISE worked together with its partners on several approaches to reduce the water consumption in CSP plants.

“I have always been interested in problems that were thought to be unsolvable.” This quote stemming from Prof. Dr. Adolf Goetzberger stands both for his scientific career as well as for his unwavering conviction as founder of Fraunhofer ISE, which he launched and led to success. Goetzberger not only advanced photovoltaic technology, a key pillar of a sustainable future energy system, but from the beginning on also incorporated research on the systemic aspects of the energy transformation at the institute, already perceiving the importance.

Concentrator Photovoltaics (CPV) has by far achieved the highest efficiency for the conversion of sunlight into electricity. The basis for this latest achievement lies in the special multi-junction solar cells as well as the perfect interplay between the cell and the module optics. In the EU-funded project CPVMatch, a consortium of research institutions and companies has demonstrated how to optimize both of these aspects and thus better exploit the potential of this technology. The achieved module efficiency of 41.4 % is the highest value ever measured for a photovoltaic module.

The Fraunhofer Institute for Solar Energy Systems ISE and Heraeus are researching and optimizing novel, selectively coated cell connectors in a joint research project. The Selectively Coated Ribbon (SCR^TM) cell connector achieves an average gain of 1.9 W in conventional 60-cell solar modules. The connector can be used in industrial PV module manufacturing without system modification and at no extra cost. Fraunhofer ISE has successfully tested modules with the SCR connector in its accredited TestLab PV Modules. Heraeus and Ulbrich developed a process for the production of the efficient cell connector and presented the new product to the professional audience in September 2018 at the EU PVSEC in Brussels.

Heat pumps are a key technology for the energy transformation, since they cover the heating demand efficiently and sustainably. While the market for heat pumps in detached and semi-detached homes is growing continuously, there is still potential for heat pump use in multi-family homes and for commercial and industrial applications. At the Chillventa, the international trade fair for cooling, air-conditioning, ventilation and heat pumps, the Fraunhofer Institute for Solar Energy Systems ISE focuses on the potential and the current challenges facing heat pumps in a special presentation. The Chillventa trade fair takes place from 16-18 October 2018 in the City of Nuremberg.

Photovoltaics is booming worldwide. If one considers PV installations in 2017, Europe has lost its pioneering role and now holds fourth place behind China, the USA and India. On the other hand, Europe is leading worldwide in PV research and development as demonstrated by the 35th European PV Solar Energy Conference and Exhibition EU PVSEC, held this year in Brussels from 24-28 September 2018. Fraunhofer ISE, Europe’s largest solar research institute, is represented at the conference with over 60 contributions in the form of talks, posters, session chairs and two plenary speeches as well as a booth at the exhibition.

Similar to the human brain, artificial neural networks develop action strategies autonomously using examples (i.e. training data) experienced in the practice. The network structure is based on the neurobiological findings on the functioning of the human brain. A logical following is to apply such network structures for the technical control of systems. The Fraunhofer Institute for Solar Energy Systems ISE has done just that and developed self-learning artificial neural networks (ANN) for controlling solar thermal heating systems in the project “ANNsolar – Neural Networks for the Use in Solar Thermal Systems.” The system gathers data on the thermal building dynamics, the change in heating demand due to the solar radiation incident on the building envelope, and the state of charge of the thermal energy storage dependent on the operating conditions. With this basis, the network can predict the future thermal conditions without a simulation. The neural networks learn the respective dependencies autonomously.

Opened as a research factory for solar cells twelve years ago, the Photovoltaic Technology Evaluation Center PV-TEC at Fraunhofer ISE is an important player in the piloting of crystalline silicon solar cells. The unique service center for the entire PV value chain helps to close the gap between research and industry, making it a pivotal driver of innovation transfer. After a fire badly damaged the facility last year, the PV-TEC technology platform was officially reopened on July 9, 2018, complete with brand new equipment.

Agrophotovoltaics (APV), a technology which combines the production of solar electricity and crops on the same land, has already been successfully demonstrated in pilot projects in several European countries. The Fraunhofer Institute for Solar Energy Systems ISE in cooperation with the Innovation Group “APV-Resola” have proven the feasibility of Agrophotovoltaics with a 194 kWp APV pilot system realized on a farm near Lake Constance in Germany. The project results showed that APV increases the land-use efficiency by 60 percent. “The next step is to establish a proof of concept for the APV system technology in developing and threshold countries. Due to the higher levels of solar radiation in these countries, APV can make better use of its strengths. The potential is enormous,” says Stephan Schindele, project head of Agrophotovoltaics at Fraunhofer ISE, who is now focusing on transferring the technology to other climatic zones as well as other applications.

The reseachers of the Fraunhofer Institute for Solar Energy Systems ISE will be presenting their newest developments on June 20-22, 2018 at the Intersolar Europe 2018 (Hall A1.540) in Munich. The highlights include novel resource-saving printing technologies for solar wafer metallization, new examples of building-integrated photovoltaics, highly compact and efficient inverters and a broad spectrum of quality assurance instrumentation and testing services as well as an innovative battery storage system for stationary applications.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE developed and successfully put into operation an inverter for direct feed-in to the 10 kV medium-voltage grid. The inverter contains high-voltage silicon carbide (SiC) transistors which allow for coupling to the medium voltage grid without requiring an additional transformer. The three-phase inverter can be used to regulate reactive power as well as to actively filter undesirable harmonics in the electricity grid. Thus, it actively contributes to the stabilization of future power grids with a large share of renewables.

Global experts in solar power believe the world will reach 1 terawatt (TW) of installed solar photovoltaic (PV) capacity within the next five years. That is the opinion voiced by 95 percent of the approximately 70 authorities who gathered in Golden, Colorado, USA for the second Terawatt Workshop held by the Global Alliance of Solar Energy Research Institutes (GA-SERI). The alliance was formed in 2012 and includes the three world leading solar research institutes, the National Renewable Energy Laboratory, NREL (USA), the National Institute of Advanced Industrial Science and Technology AIST (Japan) and the Fraunhofer Institute for Solar Energy Systems ISE (Germany).

Photovoltaics (PV) is one of the key technologies of a sustainable energy supply based on renewable energy. Besides silicon-based photovoltaics, which presently dominates the market, there are other materials, such as perovskite, that also show great potential. Scientists are testing the proof of concept of these new types of solar cells. Very innovative is a new process for fabricating solar cells using sustainable and more resource-friendly methods. Hereby the number of production steps can be drastically reduced by reversing the manufacturing process. Such an in-situ concept for printed perovskite solar cells is being developed by the Fraunhofer Institute for Solar Energy Systems ISE. With a record efficiency of 12.6 %, the researchers have now reached an important milestone in the field of printed photovoltaics.

The Fraunhofer Institute for Solar Energy Systems ISE and teamtechnik, an international leader in production technology, report that it is now possible to connect high efficiency solar cells using electrically conductive adhesives in series production. The results of the joint research project »KleVer« show that the adhesive technology is ready for the market and can be used as an alternative to the widespread soft soldering interconnection technology. Due to the much lower process temperatures of this technology compared to soldering, temperature-sensitive high efficiency solar cells can be connected using adhesives in a gentle and material-saving process. In industrial production, the throughput is only slightly lower than with soldering. The reliability of the adhesive connection was confirmed in tests carried out in a climate chamber.

The interplay between automation and energy technology, IT platforms and artificial intelligence is the focus of the HANNOVER MESSE 2018 being held from April 23-27, 2018. At the renowned international trade fair, the Fraunhofer Institute for Solar Energy Systems ISE presents innovations in hydrogen technology at the joint booth »Hydrogen + Fuel Cells + Batteries« (Hall 27, Booth C58). A highlight at the booth will be the presentation of the GreenTec Award 2018 in the category »Energy« on Tuesday, April 24th at 2 pm.

Building-integrated photovoltaics (BIPV) places high demands on solar PV module design. The aesthetics and freedom of design are just as important as the module efficiency, and in manufacturing today, a conflict often exists between individualized sophisticated design, high module efficiency and low costs. In the BIPV-Fab project, the equipment manufacturer SCHMID and the Fraunhofer Institute for Solar Energy Systems ISE investigated possibilities for manufacturing customized modules in series production. With the newly developed production concepts, the costs of building-integrated PV modules can be reduced by 35 percent.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with the company EV Group (EVG) have developed a new silicon-based multi-junction solar cell, which can convert exactly one-third of the incident sunlight into useful electricity. This newest result is now published in the renowned scientific magazine Nature Energy.

Market-oriented R&D as well as testing and certification of batteries and energy storage systems support the global energy transformation and further the expansion of electric mobility. Over 30 million euros shall be invested in the new competence center located in Freiburg, Germany.

The Fraunhofer Institute for Solar Energy Systems ISE is presenting innovative solutions and projects on renewable energy storage and grid integration at the Energy Storage Europe, the leading international trade fair for storage in Düsseldorf, Germany from March 13-15. Fraunhofer ISE is presenting at a joint booth of the Fraunhofer Energy Alliance (Hall 8b, booth B39). Parallel to the trade fair, the 12th International Renewable Energy Storage Conference (IRES) and the 7th Energy Storage Europe Conference (ESE) are taking place. They address two thematic foci: the scientific research on storage technology, legal frameworks, network and market aspects (IRES) and the business and finance aspects for the rollout of these technologies to the global market (ESE). Fraunhofer ISE researchers are involved in leading conference sessions and presenting their results in the fields of thermal and electrical energy storage, sector coupling and Power to Gas/Power to X.

With the transformation of our energy system, the fraction of electricity supplied by fluctuating renewable energy sources, such as wind and solar, will steadily increase. This requires more electric storage capacity and an energy management that responds flexibly. Together with partners, researchers at the Fraunhofer Institute for Solar Energy Systems ISE have set up a novel hybrid energy storage system on Borkum, an island on the North Sea. The system consists of a lithium ion battery and a super capacitor for short term power demands. The hybrid storage is connected to the medium voltage grid with a new type of modular inverter. During the field test lasting one year, the researchers will test and compare the different control strategies in the energy management system.