Europe is facing increasingly intense heat waves that are subjecting energy infrastructure to more demanding operating conditions. In photovoltaic installations, this trend is making the thermal safety of the modules, their performance in hot spots, their fire resistance, and their long-term reliability increasingly important, alongside efficiency and cost.
According to the European State of the Climate 2025 report, prepared by the European Centre for Medium-Range Weather Forecasts , which implements the Copernicus Climate Change Service, and the World Meteorological Organization, in 2025 above-average temperatures were recorded in at least 95% of the continent and heat waves affected large areas from the Mediterranean to the Arctic.
One of the main risks to the operation of photovoltaic modules is hot spots, which can appear as a result of partial shading, microcracks, or other internal defects. When an area of the cell stops generating current normally, the energy can dissipate locally as heat, accelerating the degradation of the materials and, in the most serious cases, increasing the risk of fire.
Faced with this risk, AIKO 's ABC (All Back Contact) modules These are the world's first photovoltaic modules to obtain TÜV Rheinland's " PV Module Anti-Ignition Hazard " certification. Under TÜV Rheinland's rigorous testing conditions, they recorded hotspot temperatures more than 35% lower than those of TOPCon modules, demonstrating their ability to reduce the thermal risks associated with localized overheating.
Furthermore, comparative shading tests show significant differences between the two technologies. Under single-cell shading conditions, AIKO's ABC modules reached a maximum temperature of 80 °C, compared to 139 °C recorded by TOPCon modules. Under broad-area shading, the maximum temperatures were 71 °C and 110 °C, respectively.
This behavior relies on two design elements of ABC technology. On the one hand, its architecture incorporates a function similar to that of a bypass diode at the cell level, which redistributes the current when an area is shaded and prevents electrical stress and power dissipation from concentrating in a single point.
On the other hand, AIKO's ABC cells use pure copper grids bonded to the silicon wafer, as opposed to conventional metallization with silver paste, a structure that improves their mechanical resistance to microcracks and reduces the risk of hot spot formation.
The protection of the modules is not limited to the hot spots generated inside them. In fire resistance tests according to IEC standards, in which they were exposed to a 760 °C flame for ten minutes, AIKO's ABC double-glazed modules achieved the highest classification, Class A, while the TOPCon modules obtained Class C.