Potential induced degradation (DIP, or more commonly PID for the English expression potential induced degradation) is a degradation in photovoltaic panels that causes loss of performance that is due to the presence of parasitic currents in them. Its potential effect can reduce the power of the equipment by up to 30%.[1]​.

The cause of these currents is due to the presence of significant potential differences between the module and ground "Earth (electricity)"). In most ungrounded photovoltaic systems, the modules have a non-zero voltage that generates this effect, although it is more frequent in negative voltages, especially when conditions of high voltages, high environmental humidity or high temperatures occur.

Potential-induced degradation has been known for years. The first publications on the subject date back to 2006 (Photon 4/2006, 6/2006, and 4/2007) although they only referred to high-performance crystalline silicon modules manufactured by SunPower. In 2007, cases were also recorded in Evergreen Solar panels (photon 1/2008 and 8/2008). Occurrences were later recorded in ordinary crystalline silicon modules (Photon 12/2010, talk by Solon SE") at PVSEC Valencia 2010). According to manufacturer Solon SE"): "At 1000 V, now a fairly common voltage in large photovoltaic systems, can be critical for each module technology".

The effect can be completely prevented if the inverter "Inverter (electronics)") presents the option of grounding the positive or negative pole. The choice of which to ground must be made according to the technology of the modules and the topology of the inverter.

If the effect has already started, it is possible to recover the affected modules. Several companies such as Vigdu, iLumen") and Pidbull, and before that SMA, market equipment capable of monitoring and reversing the condition.[2][3][4][5]​.

The phenomenon does not affect the configurations of photovoltaic installations with microinverters, since the voltages are too low to allow the appearance of Potential Induced Degradation.[6]​.