Solar Plants Damaged by Typhoons in Summer (4)

2019/12/28 10:12
Kenji Kaneko, Nikkei BP Intelligence Group, CleanTech Labo
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Continued from Solar Plants Damaged by Typhoons in Summer (3)

High-voltage sites flooded in Takasaki City

In Gunma Prefecture, the water level of the Kabura River, which flows through Tomioka City and Takasaki City, increased, flooding houses and other structures in some areas. In Takasaki City in particular, multiple mega (large-scale) solar power plants connected to high-voltage transmission lines along the Kabura River were immersed on a large scale.

The three sites affected by the flood submitted reports to the government. According to the information released by METI, solar panels, PV inverters and power receiving and transforming facilities at the three sites, featuring an output of 1.98MW, 1.75MW and 1.25MW, respectively, were flooded.

The three sites are on flat ground similar to a river terrace and are located to the north of the river, with a mountain behind. The risk of flooding seems to be very high in the event of overflowing due to an increase in the river's water level.

However, the degrees of damage are substantially different due to small differences in the location of the three sites.

The 1.98MW site, among the three sites, is about 100 meters from the river in its normal state and the facilities are installed on flat ground, which looks like the second stage of the river terrace. Because of the location, although traces of flooding are observed throughout the array area, which consists of two rows (sheets) of longitudinally arranged panels, no damage is detected on the mounting systems, perhaps because the force of the water was not very strong (Fig. 18 & 19).

Fig. 18: Traces of flooding up to top of arrays at 1.98MW site in Takasaki City (source: Nikkei BP)

Fig. 19: Mounting systems flooded but not damaged at 1.98MW site in Takasaki City (source: Nikkei BP)