Continued from Mega Solar Plants Submerged Underwater in Hokkaido (1)

Approximately 10,000 panels replaced

Nearly all the solar panels were finally replaced with new ones – about 10,000 panels in all. Upon consulting each panel manufacturer, it was learned that the panels would not be covered by the manufacturer's warranty if they are used after flood damage.

A group company of Technical Yield handles the waste treatment and recycling businesses. The company could have the damaged solar panels treated by the group company, but the operation was entrusted to an external company highly evaluated for solar panel reuse and recycling of materials, aiming to use the company's management resources with a priority on early restoration.

Notification to the Ministry of Economy, Trade and Industry (METI) was also required for replacing the solar panels because the model identical to the solar panels of Yingli Green Energy introduced at the start of operation was no longer sold; three years and six months had passed since the power plant started operation, and it was impossible to purchase the same products.

The Yingli solar panels, which were originally 265W/unit, were replaced with panels of 275W/unit, and an application for "certification of change" was submitted to METI.

As for the other equipment, PV inverters were also installed near the area where muddy water had accumulated (Fig. 12). Water reached nearly halfway up the buildings for outdoor installations, and the PV inverters manufactured by both GS Yuasa Corp and TMEIC had to be replaced.

Fig. 12: PV inverters were also replaced. Water reached nearly halfway up the buildings for outdoor installations, according to the company. The picture was taken on August 2. 2017 after restoration (source: Nikkei BP)

Only some of the step-up transformers (Cubicle) were replaced. All of the combiner boxes were replaced while cables were partially replaced. The foundations were also partially replaced. Pile foundations are used in the 1.35MW site while secondary concrete products are used in the 1MW site.

Mounting systems of both sites are made of steel and are strong enough to withstand the pressure from piles of snow. Therefore, the majority of them were reused. The removal and demolition had to be carried out carefully because the mounting systems were reused. It was easy for Technical Yield to act appropriately to these situations because the operations related to the construction were handled by a construction company in the group.