For example, juwi is said to have limited its solar panel suppliers to six firms. Solar panels manufactured by Canadian Solar Inc, one of the six firms, were used at Ozu Solar Power Plant. Also, PV inverters of Toshiba Mitsubishi-Electric Industrial Systems Corp (TMEIC), which is among the manufacturers specified by juwi, were used (Fig. 3).
"Although products of SMA Solar Technology AG of Germany are often chosen overseas, we chose TMEIC's product this time," Manager Kasama said. "Both manufacturers' PV inverters are almost equally excellent in efficiency and reliability. But we preferred TMEIC's PV inverter to SMA's. TMEIC's product is housed in a building whereas SMA's is not. Therefore, there is less risk of noise that would trouble neighboring residents."
On the other hand, the plant employed an imported wiring facility and mounting system specified by juwi (Fig. 4). The mounting system is a product of Schletter GmbH of Germany (Fig. 5). Schletter is the world's leading manufacturer of mounting systems for solar power generation, and its products are said to have been deployed as much as about 10GW thus far, primarily in Europe and the US.
Its products feature a construction method that involves heavy machinery digging a hole in the ground and driving a stake into that hole. Many mounting systems made in Japan are supported by stakes driven into the ground at two spots on the rear and front sides of panels tilted on the mounting system. Schletter's products can be set up in a short period because they use fewer stakes; holding the panels on both sides with only one stake provides sufficient strength.
It reportedly only took just under a week to set up the mounting systems at Ozu Solar Power Plant. However, special heavy machinery is required to drive the stakes for Schletter's mounting systems, and there are currently only five such machinery units in Japan.
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