On March 10, the National Institute of Technology and Evaluation (NITE) announced that among the small-output power generation facilities stipulated by the Electricity Business Act, solar power generation facilities in the low-voltage business category of 10 kW or more and less than 50 kW, and wind power generation facilities of less than 20 kW. We published an accident report on the equipment. Aggregated as "FY2021 Small Output Power Plant Accident Summary Material".
Accident damage/reported number of low-voltage commercial solar power plants
(Source: NITE)
According to the same data, there were 220 reports of accidents at small-output power generation facilities in fiscal 2021, of which 213 were for solar power and 7 for wind power. About 97% of the accident reports were major electrical work damage accidents, and there were no serious accident reports involving casualties.
Accident damage and reported cases of small-scale wind power generation facilities
(Source: NITE)
A total of 260 cases of accidental damage (number of damaged electrical structures) occurred at photovoltaic power generation facilities. Of these, 159 were for power conditioners (PCS), accounting for 61%. Solar panels accounted for 53 cases, 20%; supports (mounting), 46 cases, 18%; and supports (foundation), 2 cases, 1%.
The cause of the accident was poor maintenance - natural deterioration accounted for 136 cases (52%), and damage to the PCS was the main cause. Natural disasters accounted for 101 cases, accounting for 39%, and the breakdown was 57 cases of ice and snow, 19 cases of wind and rain, 12 cases of flood damage, 10 cases of landslides and avalanches, and 3 cases of lightning. There was a lot of damage caused by snow, ice, wind and rain on solar panels and mounts.
There were a total of 7 accidental damages to wind power facilities, including 4 for supports (towers), 2 for nacelles, and 1 for yaw drive units. The cause of the accident was that the tower was broken due to loose bolts due to lack of maintenance and inspection, and property damage accident that damaged cables of other electric power companies in one case, damage to the yaw drive system due to contact with wildlife in one case, and a wind turbine fire. 1 case of nacelle failure. The remaining four cases are under investigation, but it is said that many of the towers were broken due to factors such as strong winds.
