The oldest known photovoltaic power station in Europe, located in the canton of Ticino in southern Switzerland, this 10KW power generation system installed on the roof of the laboratory of the Swiss University of Applied Sciences and Arts, referred to as TISO‐10, has been running almost continuously since it was connected to the grid. 40 years.
Recently, the Swiss Federal Office of Energy invited two scientists from the Swiss Federal Institute of Technology in Lausanne and their research team to study the power station, and the results proved that the operation is good!
1. An old power station with a 40-year lifespan
The construction cost of the TISO-10 power station was about $475,000 at the time (about $309,000 today), and the cost of all 288 modules in the project was about $37/W. The output power per module of this glass-backed panel 37W.
Although the electrical layout of the TISO-10 power plant system has undergone several changes, except for a few inverter replacements, all components have been used to the end, always exposed to the outdoors and sunlight, and have not undergone renovation or modification. , there are very few modules with junction boxes and bypass diodes replaced.
“The mechanical strength of these components is astonishing,” the two scientists emphasize, closer to what we define today as double-glass components.
2. 40 years of change
The component performance of the TISO-10 plants varies significantly. The researchers divided the panels into three groups, with the best-performing modules showing little yellowing, while the other two groups showed moderate to high yellowing.
The encapsulation materials for the three groups of panels are all fabricated from PVB, but with different additives, resulting in different properties. “The details make or break! In this case, changing just one additive in the encapsulation material can affect the performance of the entire photovoltaic plant. This shows that the choice of encapsulation material is critical!” explained the researchers.
In addition, the inverter has been replaced five times in 40 years.
3. Power Attenuation
About 21.5% of the modules show a -0.2% annual decay, which is also in line with the data promised by the manufacturer. Scientists say most of the components performed well, meeting initial expectations. That is to say, at least 70% of the components in this power station meet the service life of 35 years.
The researchers emphasize that the first and most important lesson from PV plant installation and module research is that the bill of materials (BOM) is critical. The choice of material is just as critical today as it was forty years ago.
4. The oldest power station in China is still in stable operation
In Gansu, China, there is also an old power station built in 1983. It has a history of 38 years so far. Although the 10kW at that time has been reduced to 7kW, it is still generating stable power!
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