Principle of a silicon singlet fission solar cell with incorporated organic crystalls. M. Künsting/HZB

The efficiency of a solar cell is one of its most important parameters. It indicates what percentage of the solar energy radiated into the cell is converted into electrical energy. The theoretical limit for silicon solar cells is 29.3 percent due to physical material properties. In the journal Materials Horizons, researchers from Helmholtz-Zentrum Berlin (HZB) and international colleagues describe how this limit can be abolished.

From wood waste to high-performance polymers: Terpenes from turpentine are converted to bio-based, transparent and heat-stable polyamides under application of a new catalytic process. Fraunhofer IGB

The natural substance 3-carene is a component of turpentine oil, a waste stream of the production of cellulose from wood. Up to now, this by-product has been incinerated for the most part. Fraunhofer researchers are using new catalytic processes to convert 3-carene into building blocks for biobased plastics. The new polyamides are not only transparent, but also have a high thermal stability.

For their tests, the scientists coated a conventional heat exchanger with the new material, in cooperation with colleagues from the Fraunhofer Institute for Solar Energy Systems. Photo: Dirk Lenzen

Waste heat from industry can often not be utilised because of its low temperature. With this material, it can be used in environmentally friendly cooling systems for example in the field of building technology. The research team from Kiel will present its material and its applications at the Hannover Messe 2018. Cooling devices are considered to be power guzzlers, in which polluting refrigerants are still used, even after the ban on chlorofluorocarbons (CFCs). An environmentally friendly alternative are systems which use water instead.

The test cell has been successfully implemented in research projects at Fraunhofer ISE and duplicated for project partners. Fraunhofer ISE

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.