``Claw marks'' left on solar power plants by ``heavy snowfall in the 3rd year of Reiwa'' revealed by melting snow
Panel detachment/damage, foundation subsidence, frame deformation and even total collapse
I can't stand it even with snow country specifications...
From January to February 2021, heavy snowfall will hit a wide area, mainly in Hokuriku, Tohoku, and Hokkaido. In addition, many people died in accidents during snow removal.
This "Reiwa 3rd year heavy snowfall" was characterized by a large amount of snow that fell and piled up in a short period of time. Some areas in Niigata Prefecture experienced heavy snowfall exceeding 1m in 24 hours. In Joetsu City, snow fell intensively over the three days from January 8 to 10, reaching a maximum depth of nearly 250 cm. In terms of the deepest snowfall, Iwamizawa City, Hokkaido, recorded 142cm in December, which was the highest in the history of observation, and Toyama, Niigata, and Akita prefectures also experienced record amounts of snowfall.
Among the solar power plants in these areas, there are sites where the solar panels have come off and damaged, and the foundations and frames have been deformed. Such damage is difficult to grasp when the tree is buried in snow. The full extent of the damage has become clear, with scattered panels appearing as the snow melts in spring.
Originally, solar power plants in snowy regions were designed to cope with snow accumulation to some extent. The installation angle of the array (solar panel installation unit) is tilted to about 30 to 40 degrees to make it easier for snow to slide off. Many sites secure a large installation height of about 1 m from the lowest part.
However, when there is a heavy snowfall in a short period of time like this time, a large amount of snow piles up on the array before it slides off the solar panel, placing a heavy load on the mounting frame. If the columns that support the rear of the array cannot withstand this load and are crushed to the north, the entire frame will collapse.
This is the situation at a high-voltage interconnected mega solar power plant (large-scale solar power plant) that has been in operation since 2013 near the coast of Joetsu City, Niigata Prefecture. Solar Frontier's CIS compound type thin-film solar panels were assembled in four stages and installed at an installation angle of 30 degrees and an installation height of about 1 m. I'm in. Each panel is supported by a column, and it is shocking to see how the sturdy-looking steel frame is bent. (Fig. 1) (Fig. 2).
Fig. 1●High-voltage interconnection site near the sea in Joetsu City, Niigata Prefecture. Areas to the north were crushed by snow
(Source: Nikkei BP)
Figure 2 ● A high-pressure site near the sea in Joetsu City. Supports that look sturdy are bent together
(Source: Nikkei BP)
This high-voltage solar power plant is divided into two sections, with about one-third of the total being installed in the northern area near the sea. The trestle was severely damaged in the sea side area, and no major damage was seen in the other south side area. Among the seaward areas, the southern array is partially damaged (Fig. 3) (Fig. 4).
Figure 3 ● A high-pressure site near the sea in Joetsu City. Less snow damage on the south side
(Source: Nikkei BP)
Figure 4 ● A high-pressure site near the sea in Joetsu City. There is a tendency for the collapse of the array center to be large
(Source: Nikkei BP)
Looking at this damage situation, it can be seen that even at a single mega solar site, the way snow accumulates varies depending on the location due to subtle differences in the surrounding environment such as topography and forests. At this site, the forest is looming to the north, and the northern area may have become a snowdrift.
