First bifacial PV modules early 1983

A pioneer experience with the production and first commercialization of bifacial PV modules was developed by ISOFOTON, a Spanish academic spin-off established in 1981. Bifacial modules based on n-PERT cell technology were produced until 1989. 59 modules from that time were recovered from real installations after about 20 years of outdoor exposure. After cleaning and testing, 56 of these modules were connected to the grid at an IES-UPM terrace in Madrid on the 5th May 2021, constituting a 3.79 kW PV generator (nominal power of the frontal side), which is now in routine operation. The good health of these modules translates into yearly Performance Ratios of 88% (referred to the frontal side irradiation) and 81% (referred to the frontal plus rear irradiation). The com-parison of the design and features of old and modern bifacial modules allows the evolution of PV technology throughout the last three decades to be appreciated.

Automated summary

This study describes the production and commercialization of bifacial PV modules, and presents the results of an outdoor test on 59 modules recovered from real installations after 20 years. The study confirms that these modules continue to perform well after cleaning and testing.