Press Releases

In Germany alone, about one million high-performance batteries from e-bikes and scooters end up in the trash prematurely every year, even though they often still retain a large portion of their capacity. At the same time, stationary energy storage systems are expensive and resource-intensive to manufacture. The Freiburg-based startup EDENenergy solves both prob-lems: It develops modular industrial storage systems from second-life batteries that are high-performance, cost-effective, and sustainable. Former researchers at the Fraunhofer Institute for Solar Energy Systems ISE have developed a system featuring interchangeable battery modules and flexible power electronics that efficiently and safely combine heterogeneous batteries into stationary storage systems.

What would happen to the price of electricity if significantly more battery storage systems were traded on the market? The Fraunhofer Institute for Solar Energy Systems ISE is releasing a price simulator today on its Energy-Charts.info platform that answers this question using real market data. The tool uses the actual buy and sell bids from the daily electricity exchange auction and adds a freely selectable number of battery storage units. For each quarter-hour, users can see how the exchange electricity price would have changed, how the batteries charge and discharge, and what their charge levels are. The freely accessible simulator is updated daily with the latest electricity trading results.

Researchers at Fraunhofer ISE have developed a prototype of a manufacturer-neutral app for heating, ventilation, air conditioning and plumbing contractors that enables the virtual planning of heating systems. Unlike software tools already available, the “Heat Pump PlanAR” app combines various steps of the planning and installation process into a single application. The software prototype is the result of the “WESPE” collaborative project led by the Zentralverband Sanitär Heizung Klima (Central Asso-ciation for Plumbing, Heating, and Air Conditioning) ZVSHK and was designed in close collaboration with trades businesses. The application is now set to be further developed in collaboration with interested software companies and brought to market.

Since 1986, the calibration laboratory at the Fraunhofer Institute for Solar Energy Systems ISE has been measuring solar cells, and since 1991, photo-voltaic (PV) modules as well. Over the course of its forty-year history, it has calibrated the performance of thousands of solar cells and modules using a wide variety of technologies. To date, the “CalLab” has confirmed 152 record results. Sixty-six of these records were for PV modules—primarily silicon modules—while 86 referred to solar cells. The first record was set in 1992 by a mini silicon solar module with an efficiency of 16.4 percent, submitted by Deutsche Aerospace Aktiengesellschaft and featuring Bayer silicon wafers. The most recent record measured by CalLab confirmed that a module from AZUR SPACE, temicon and Fraunhofer ISE, with an efficiency of 34.4 percent, is currently the world’s most efficient solar module.

Together with partners from research and industry, the Fraunhofer Institute for Solar Energy Systems ISE has modified the structure of battery electrodes so that the battery cells can store 10 to 15 percent more energy at the same weight. They achieved this by more than tripling the coating thickness of the battery electrodes—for example, in lithium-ion batteries—which simultaneously reduces the number of current collectors in the battery cell. The research team implemented the new electrode architecture in lithium-ion pouch cells manufactured using industry-standard processes. Furthermore, they successfully applied the concept to zinc-ion and sodium-ion battery cells.

The more than 23,000 large aircraft worldwide consume approximately 350 billion liters of fuel annually and account for about 3 percent of human-caused CO2 emissions. For long-haul flights over 4,000 km in particular, there is no alternative to liquid fuels, as only these provide a sufficiently high energy density. The development of sustainable aviation fuels (SAF) has now reached an important milestone: Following successful qualification by the international standardization organization ASTM, methanol has been recognized as an approved feedstock for the alcohol-to-jet production pathway. This means that in the future, methanol-to-jet blending components can be produced and mixed with at least 50 percent by volume of conventional kerosene to create a “drop-in” fuel—one that is fully compatible and can be used without any modifications to aircraft, engines, or existing infrastructure.

Organic solar modules score points for their flexibility, transparency, and a particularly good environmental footprint. Wavelength-dependent transparency, in particular, is a major strength of organic photovoltaics. Researchers at the University of Freiburg and the Fraunhofer Institute for Solar Energy Systems ISE have now succeeded in building 14.5 by 14.5- centimeter organic PV modules with an average transparency of 43.2 percent and an efficiency of up to 9.26 percent. To achieve this, they used a combination of sputtering and slot-die coating – both processes that are industrially proven and highly scalable to large module areas.

The American company Source Energy and the Fraunhofer Institute for Solar Energy Systems ISE have jointly developed a new product line for space satellites based on silicon solar cells. The solar arrays are using a special interconnection technology. Combined with inexpensive silicon solar cells, this enables modules at much lower costs compared to standard III-V technology that currently dominates the space sector. The automated production process, utilizing the M10 Solar Equipment GmbH’s Shingle-Matrix Stringer, allows Source Energy to delivery their products in less than six months from the time of order.

Heat pumps can replace existing gas and oil heating systems in multi-family houses when the entire system is designed to match the building. This is the core finding of the "LC R290" research project, in which the Fraunhofer Institute for Solar Energy Systems ISE worked with a consortium of twenty companies from the heating industry and housing sector to develop typical solution concepts for heating system replacement. The project team used the refrigerant propane (R290) for this purpose.

The share of renewable energy in Germany’s net public electricity genera-tion—the actual mix of electricity coming from the outlet—stood at 61.8 percent in the first half of 2026. Wind power increased its generation by 12.2 percent compared to the previous year, while the electricity feed-in from photovoltaics reached a new record of 43.2 terawatt-hours. Strong generation from renewable sources ensured that electricity prices in the spring were largely decoupled from the rise in gas prices caused by the war in Iran. This is according to an analysis by the Fraunhofer Institute for Solar Energy Systems ISE based on data from the energy-charts.info platform.