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Major Typhoon Damages Floating Mega Solar Plant (page 4)

Causing fire, piling up of panels

2019/09/30 13:12
Kenji Kaneko, Nikkei BP Intelligence Group, CleanTech Labo
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Mounting systems at southern end torn and curled up

The floating mounting systems at the southern end of the separated island were curled up by the strong wind, piling up like a roll cake (Fig. 9).

Fig. 9: Southern end of separated islands curled up, exposing back sides of panels (source: Nikkei BP)

Floating mega solar power plants in Japan have been damaged by typhoons in the past. At a 1.99MW floating mega solar power plant installed on a pond in Osaka Sayama City in Osaka Prefecture, the floating mounting systems were curled up by typhoon No. 21 last year, causing warping in 733 solar panels, for example.

The phenomenon of curling up at ends of "islands" was observed generally in floating solar power plants damaged by strong wind in the past. Because of this reason, measures to prevent "curling up" were incorporated, including the increase of the weight of floats along the outer ends of islands.

In the disaster at the Yamakura Dam site caused by the typhoon, mooring wires lost their function and the "island" was pushed away significantly, in addition to "curling up" at ends of the islands. Measures including improving the design strength of the mooring wires and anchors at the bottom of the pond will be required in the future (Fig. 10 & 11).

Fig. 10: Area where front island separated from back island (source: Nikkei BP)

Fig. 11: Scene of separated area before disaster. Originally composed of single island (source: Nikkei BP)

However, the administrator of the pond does not want to make large-scale modifications to the bottom structure. Therefore, mooring wires may be connected to weights placed on the bottom depending on the case. Advanced skills for construction and technical renovation are expected for stable operation of floating mega solar power plants in the future, as strong typhoons often strike Japan.