Betsukawa Corp (Hakusan City, Ishikawa Prefecture) has its headquarters factory in an industrial area in Hakusan City (Fig. 1). The location is about 10km from the Japan Sea and near the Tedori River.
Betsukawa is engaged in developing electric power facilities such as extra-high-, high- and low-voltage switchboards. A mega- (large-scale) solar power plant with an output of about 1.4MW was set up on the roof of the headquarters factory and started operation in September 2016.
The power producer is Orix Corp, which leases the roof from Betsukawa to run the solar power generation business on it. A total of 8,224 solar panels were arrayed on the roof, which measures about 13,077m2.
For this rooftop mega-solar plant of Betsukawa, Nippon Comsys Corp was responsible for design and construction while Solar Frontier KK (Minato-ku, Tokyo) and Toshiba Mitsubishi-Electric Industrial Systems Corp (TMEIC) supplied solar panels and PV inverters, respectively (Fig. 2).
In the Hokuriku region, Orix frequently adopts Solar Frontier's CIS compound-type panels. Orix values the panels' property to generate more power than the crystal silicon type even during hours with less sunshine.
Meanwhile, Orix uses different manufacturers' PV inverters in accordance with the plant scale, intensively adopting TMEIC products at mega-solar plants. The company said TMEIC products were superior in terms of operational cost efficiency, taking into consideration their higher conversion rates and other properties.