Photovoltaic system retains nearly 80% output after 30 years of operation.

The modules of a 31-year-old photovoltaic system have been tested for their performance and still achieve almost 80 percent of their original output. This was reported by the French non-profit organization Hespul, which built the first photovoltaic system in France to be connected to the electricity grid in 1992 with the help of EU funding. After 30 years of operation, Hespul tested the solar system with the support of the French certification body Certisolis and the company Isowatt, among others.

To this end, the modules were dismantled and examined in the laboratory in accordance with international standards, as Hespul reports. The panels were exposed to flashes of light in a dark chamber at a constant temperature to measure their maximum instantaneous power, according to the trade journal PV-Magazin. The performance thus confirms the manufacturers' current promise that 80 percent of the module's output will be retained after 25 to 30 years.

Europe's oldest PV system in Switzerland

According to Hespolis, this confirms various research results, including those of the National Renewable Energy Laboratory in the USA and the University of Ljubljana in Slovenia, as well as regular measurements of a PV system in Switzerland that was connected around 40 years ago.

According to the Swiss Federal Office of Energy's magazine Energeiaplus, the PV system in Lugano, which has been connected since 1982, is the oldest system to be connected to the public grid. Equipped with 288 modules, the Ticino Solare plant, TISO-10 for short, still works almost as efficiently today as it did back then. After 35 years of operation, the system would show "signs of wear and tear - corrosion, burnt areas (hot spots), cracks in the cells or defects in the connecting cables". However, this system also still produces 80 percent of its original output.

(mack)