bifacial n type solar modules indoor and outdoor evaluation

• DOI: 10.4229/eupvsec20142014-5cv.2.11
• Publication Date: 2014-01-01
• Authors: L. Popescu; Thomas Baumann; T.S. Böscke; Hartmut Nussbaumer; Daniel Schär; R. Harney; C. Comparotto; J. Lossen; V.D. Mihailetchi; Matthias Noebels; A. Edler; Franz Baumgartner; J. Ranzmeyer; T. Klaus
• Keywords: 13. Climate action; PV Modules; 02 engineering and technology; OPERATIONS, PERFORMANCE AND RELIABILITY OF PHOTOVOLTAICS (from Cells to Systems); 0210 nano-technology; 7. Clean energy

29th European Photovoltaic Solar Energy Conference and Exhibition; 3248-3250<br/>There is an increased energy yield for n-type bifacial solar modules as compared with n-type monofacial modules. However, the benefit of bifaciality depends on several factors, such as module height, ground reflectivity, distance between modules, etc. This work enriches the understanding of the correlation between laboratory measurements and outdoor performance of bifacial modules. Indoor measurements of monofacial and bifacial modules, containing n-type bifacial cells of similar technology, were performed at PI Berlin (Germany). Their outdoor performance was monitored in El Gouna (Egypt), where the yield in terms of Wh/Wp was compared, and in Winterthur (Switzerland), where the influence of module height and ground reflectivity was studied. In El Gouna, an average yield gain of 22.3% in terms of Wh/Wp was measured for a bifacial module as compared with a monofacial module, over the first eight months of 2014. A maximum average monthly gain of 25.6% was reached in the month of August. A peak power output of 426 W was registered. In Winterthur, the application of a white foil beneath a bifacial module showed a gain of 7.6% in power output divided by the incident irradiance on the front side, as compared with a gravel covered ground. The power/irradiance gain was 9.7% when the module was raised from 0 cm to 64 cm above the ground level.<br/>