Norwegian scientists have used varied imaging and characterization methods to investigate cells and different parts of silicon PV modules which have been put in within the discipline for greater than 10 years. The aim of the group is to isolate the function of moisture within the completely different mechanisms that trigger the lack of efficiency over time, and to grasp how these mechanisms develop within the long-term set up of the true exterior circumstances.
Making parts that may stand up to outside set up for years and even a long time, in any kind of local weather, whereas sustaining not less than most of their preliminary efficiency, is a key aim for photo voltaic. business.
There have been many developments, with each technological progress and competitors between producers driving greater product and efficiency ensures, and subsequently longer contracts for the sale of electrical energy from one photo voltaic undertaking. Most producers now provide 30-year warranties that assure not less than 80% of the preliminary efficiency of the modules, and one even extends it as much as 40 years.
However for photo voltaic installations many areas are focused, for 2050 and past, even longer life is required, particularly for installations positioned in troublesome local weather areas even due to warmth, chilly, humidity, mud or different circumstances. And this implies understanding precisely how PV modules are likely to degrade below these circumstances.
Scientists led by the College of Agder in Norway determined to give attention to deterioration because of humidity – that is the primary attribute of the local weather in Grimstad the place the college is predicated.
The staff took modules from a decommissioned PV array put in within the city in 2000 and used quite a lot of methods, each non-destructive and damaging, to look at the internal workings of the modules, and the way the completely different parts have occurred over time within the discipline.
Their outcomes are described in full within the paper “Moisture induced degradation in field-aged multicrystalline silicon photovoltaic modules,” printed in Photo voltaic Vitality Supplies and Photo voltaic Cells. The research discovered that moisture ingress causes the deterioration of the encapsulant, producing acetic acid and varied substances that promote corrosion and different forms of degradation of silicon cells. Moisture has additionally been discovered to play a significant function in corrosion of solder joints – inflicting result in corrosion reasonably than the “sacrificial” tin hooked up to the solder.
The scientists behind the work acknowledge that PV supplies and manufacturing processes have improved considerably for the reason that modules on this research had been developed greater than 20 years in the past. Nonetheless, whereas accelerated testing is beneficial, they are saying that finding out modules with age within the discipline continues to be wanted, and most of the mechanisms revealed on this research are nonetheless related to modules working on manufacturing traces. at present.
“Though photo voltaic PV module supplies and expertise have advanced over time, the MID mechanisms of photo voltaic PV modules seem to observe the identical development,” they mentioned within the paper. “Thus, the insights from this work can information present and future decision-making relating to understanding the reliability of efficiency of photo voltaic PV vegetation.”
This content material is protected by copyright and might not be reused. If you wish to cooperate with us and wish to reuse a few of our content material, please contact: editors@pv-magazine.com.
