In the article entitledBecause the photovoltaic system produces less energy we have analyzed all the most common causes that lead to a decrease inyield of photovoltaics. A solar system produces little when one or more of its components have been compromised.
Furthermore, in the same article we have seen how small defects in the electricity grid can cause a sharp drop in production. If you have ruled out all the causes already mentioned, it is likely that the malfunction of the system is related to the state of the cells. In this context, a thermography with thermal imaging camera. On this page we will analyze in detail the case of a photovoltaic system that does not producedue to a direct cell problem.
When aphotovoltaic system does not producea cell failure must not be excluded, in fact 3 non-functioning cells are enough to compromise not only the production of a panel but also the entire string.
Thermography for photovoltaic systems
What is one forthermography?
Photovoltaic technology is reliable and solid, however, failures can occur inside the modules. When this happens, the damaged cell behaves like areverse biased diode, so as to trigger a sort of chain reaction that compromises the production of electricity on all the other cells connected in series.
When installing aphotovoltaic system, the technicians prepare by-pass diodes on most of the photovoltaic panels, so, if one fails, the others continue to produce energy and the damage is limited to one module; unfortunately in practice this ideal model does not always win, so a 3-cell failure can compromise the entire system.
This effect is calledHot Spot, literally “Hot Spot”, precisely because it determines the heating of the photovoltaic cells involved. The temperature difference can vary from a few degrees up to several tens.
The temperature difference cannot be observed with the naked eye, which is why the instrumental intervention of one is requiredthermal imaging cameraso as to produce athermographydesigned to highlight "hot spots". If yours photovoltaic system does not produce energy, this problem may have occurred: in some cases, the failure of a few cells has even caused a decrease in yield of photovoltaics 90%.
When it is necessary to proceed with an instrumental intervention withthermal imaging camera?
Therethermography is necessary when thephotovoltaic system does not produceenough energy and the other more common hypotheses analyzed in the article mentioned in the introduction have already been discarded.
What happens after the thermography?
If thethermographyhas detected anomalies on your mono or polycrystalline silicon panels, it will be necessary to proceed with the replacement of the faulty cells or with the insertion of appropriate bypasses in order to limit losses. This final step can only be accomplished after analyzing the thermographic images produced by a thermal imaging camera. Six photovoltaic modulesare still under warranty, the user can return it and wait for a free replacement,