The expertise of the Fraunhofer Energy Alliance runs along the entire value chain of silicon photovoltaics. It spans the entire range from the crystallization, wafering and cell production through to the interconnection of modules. Experts at Fraunhofer develop optimized overall system designs and are leading in the inverter technology. For concentrating PV systems, highly efficient III-V multi-junction solar cells and optical systems are developed to bundle the sunlight. The portfolio also includes silicon thin-film cells and the usage of alternative material systems. In the up-and-coming sector of organic solar cells and dye-sensitized cells, research is conducted on the improvement of efficiency and long-term stability.
Solar thermal energy
Apart from the photovoltaic power generation, concentrated solar power plants (CSP) are gaining importance, especially in regions with high direct radiation. For this, the Fraunhofer Energy Alliance does not only develop overall concepts but also the necessary components like heat storage technologies and concentrating optics with a focus on Fresnel collectors and absorber tubes.
The Fraunhofer Energy Alliance is researching systems for the thermal exploitation of solar energy in the areas of solar service water heating, space heating, process heat for industrial processes and solar refrigeration. To that end, researchers develop collectors and system components and design complete systems, which are tailored to the respective load profile and the available solar radiation including control units and the integration of cold and heat storages.
Wind turbines continue to get larger and heavier and, thus, place new demands on materials and construction. In order to prove the technical reliability of these turbines, special testing procedures and simulation methods are being developed. For example, the stability and structural dynamics of rotor blades and supporting structures are being examined. In the sector of offshore wind power, experts carry out site investigations and aeroelastic simulations in order to define the overall dynamic of the offshore wind turbine in combination with factors such as wind, sea condition and subsoil. Moreover, the Fraunhofer Energy Alliance develops strategies and technologies for maintenance and offers comprehensive services for the management and grid integration of wind turbines.
The portfolio of the Fraunhofer Energy Alliance also includes the operation of pilot plants to examine the combustion and emission behavior of different fuels in combustion plants, gasification plants and pyrolysis plants. Researchers at Fraunhofer improve system components, for example by using innovative ceramic materials in burners, advise customers with regard to the management of biomass-fired cogenerations plants and examine production chains of bioenergy raw materials. At the same time, research is conducted with respect to catalytic processes and the improvement of refinery concepts for the processing of biofuels, for example the fluid phase transition of greases, oils and renewable raw materials to biogenic diesel and gasoline.
Further research topics at Fraunhofer include crushing, blending and molding units for the conversion of waste and production residues to alternative fuels and the analysis of small-scale combustion installations with integrated cogeneration systems for alternative fuels from high calorific waste.
Experts at Fraunhofer develop, plan and support plants for biogas anaerobic digestion and conduct research on the production of synthesis gas from biomass for the usage in fuel cell systems and the coupling with chemical processes. The latter also includes the feed-in of biogas into the natural gas grid and the conversion to fuel for vehicles.
The Fraunhofer Energy Alliance develops new technologies for the usage of hydropower, both small and large scale. For example, researchers at Fraunhofer have developed an innovative power generator that uses wastewater to economically generate electrical energy even with small amounts of water and low pressure differences.
Experts at Fraunhofer see great potentials in the research field of marine energy. For this purpose, innovative technologies and regulatory approaches for marine current turbines are being developed. Furthermore, subsea pumped-storage power plants offer a completely new storage method. They use the sea as the upper reservoir and a hollow body on the seabed as the lower reservoir.
System integration and energy policy for renewable energy sources
Research at Fraunhofer particularly features the interconnection of renewable energy development (sun, wind, bioenergy, hydropower) and solutions for its technical system integration, but also the economic systems analysis and innovation research. By combining these competencies, the Fraunhofer Energy Alliance can technically, economically and politically support the energy revolution and, based on national and international market analyses, identify long-term technology trends in the field of renewable energy sources, which offer a basis of decision-making both for politics and industry.