PID - A power degradation caused by polarization and leakage currents in the PV module
„A risk factor for the electricity produced from PV modules which now occurs with many solar power systems is the so-called potential induced degradation (PID) of solar modules. As a result of this effect, the performance of the modules decreases with ever increasing significance over time. In most cases the PID process is reversible, provided that timely measures are taken. The failure to take any countermeasures though can cause damage to the affected modules permanently“.
If the modules have a negative potential to earth in operation, there is an equally high negative voltage between the cells of the PV module and the aluminum frame.
The effect is stronger, the closer the module is to the negative pole of the PV array, as the potential there (and thus the voltage between cells and the aluminum frame) can reach more than half the amount of the array voltage.
As a result, electrons from the materials used module can separate, follow this electric field and finally flow out via the aluminum frame (leakage currents). The result is an increasing charge (polarization) of the module.
- The quality of your modules (e.g. the material composition).
- The system configuration (e.g. the length of the module strings, the inverter type).
- Climatic conditions (High ambient temperature, high irradiation, high humidity, ...).
- Falling PR performance of your photovoltaic system by up to 50% in a very short time.
- Permanent damage to the photovoltaic modules which you use.
- Earnings losses and declining returns can put your loan repayment at risk.
- Raising the entire PV generator to a high positive potential relative to the earth potential by using the PADCON Float Controller.
- Use of PV system monitoring for the continuous supervision of earnings.
- Immediate PID protection for your photovoltaic system.
- Regeneration of your photovoltaic installation on up to 100% of the nominal capacity is possible
- Securing your returns