MBJ Services, an independent service provider, assessed a 5.44-kilowatt system near Bremen (Germany) which had been in operation for nearly ten years. They measured each of the 34 aleo modules’ performance with the help of a flasher. The result: an average degradation level of 2.73%. Photovoltaic system planners generally presume performance losses of 0.5% per year but the aleo modules only degraded by about half that much.
The aleo S_02, a module produced in 2002 in the town of Prenzlau in Brandenburg, was also checked for cell damage using electroluminescence. The conclusion drawn by MBJ’s Eric Lohse: "The solar modules display not only extraordinarily low degradation levels, but are also otherwise in excellent condition."
The system analysed was constructed in a barn on the Oldendorf Community Farm, and delivered 43,576 kilowatt hours (kWh) over nine years. At around 950 kWh per installed kilowatt of nominal power, its specific annual yields were significantly higher than the regional average of 883 kWh. "We turned to photovoltaics early on so that we could generate environmentally friendly energy," says farm representative Uwe Hach.
"The fact that our system’s performance has hardly diminished over a decade is a clear testament to the quality of the aleo modules." Thanks to its minimal degradation, their system will continue providing high yields for many years to come and when their feed-in compensation expires in ten years, they can expect it to yield plenty of energy for their own use.