Fire incidents involving photovoltaic systems – An analysis of different national statistics

Abstract

With the increasing number of PV installations, reported PV-related fire incidents are receiving greater attention, although their quantification depends strongly on how such events are recorded. To manage fire safety risks in PV systems effectively, accurate statistics on the probability and consequences of these incidents are essential. National statistics from the UK, Italy, Sweden, and Slovenia were analysed to examine how differences in reporting methodologies influence the observed fire statistics. The findings indicate that different measures may be relevant for assessing ignition frequency. When comparing reported fire numbers, the rate ranges from approximately 4-11 fires per GW annually in the UK, Italy, and Sweden, to about 37 per GW annually in Slovenia. Similarly, the number of incidents per 100,000 installations was found to be approximately 5-22 for the UK, Italy, and Sweden, compared with 75 in Slovenia. These differences are likely influenced by variations in data collection methods and inclusion criteria across the countries. Swedish data also show notable differences in the various measures depending on system size. In the Swedish dataset, DC cables and connectors are the most frequently identified ignition source. Regarding consequences, about 68 % of fires remain confined to the PV equipment, while 24 % damage adjacent surfaces. In 5 % of cases, significant fire spread occurred, while in 3 % the building was completely destroyed. The similarities and differences in the national statistics highlight the need for harmonised data collection to enable meaningful comparison and support data-driven fire safety measures for PV systems.