German and American researchers will work together more closely on solar energy topics as a result of the signing of a Memo of Understanding (MOU) between the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL) and the German Helmholtz Association. The MOU identifies several key solar energy topics to explore for joint research cooperation.
Scientists from the two countries, among other endeavors, will cooperate to synthesize and characterize novel materials that are candidates for more efficient solar cells and solar fuels.
They’ll also develop and use fast imaging techniques to help characterize thin-film materials on the micrometer to nanometer scale, and to characterize in situ growth processes.
They’ll seek a fundamental understanding of grain boundary/interface passivation in thin-film silicon and search for the potential and limits of wide band-gap thin-film solar cells. Thin films, made of copper, indium, gallium, selenium and other emerging materials, could potentially replace silicon as the most efficient materials in next-generation thin-film solar arrays.
To measure performance and reliability of solar cells and modules, the scientists will use electroluminescence, photoluminescence and thermography. They will also investigate the stability of solar cells by subjecting them to high temperatures and light exposures.
New device structures and lower cost catalysts will also be investigated for the generation of hydrogen in photocatalytic solar fuel generation.
The MOU was signed in Berlin by NREL Director Dan Arvizu, and leaders of three research institutes within the German Helmholtz Association – the Research Center Jülich (FZ Jülich), the Helmholtz Center Berlin (HZB), and the German Aerospace Center (DLR).
"This agreement promises to advance the state of knowledge and the development of new materials and technologies that will form the basis of next-generation solar cells and solar fuels," NREL Director Arvizu said.
In one area, the work builds on an MOU NREL signed two years ago with one of the German organizations, DLR, which involved developing standard test methods to quantitatively assess the reflectance and durability of solar mirrors used for concentrating solar power (CSP) systems. The MOU also called for round robin testing of commercial reflector samples and commercial parabolic trough receivers. In the new MOU, this work will be extended to understanding fundamental mechanisms for soiling rates on CSP mirrors.
Overall, the new MOU sets the basis for collaboration on basic and applied research issues to advance the next generation of solar cells for electricity and solar fuel production. It also addresses the improvement of the performance of concentrating solar thermal power systems.
