Daiwa Energy Co Ltd started operations of a 2.65MW mega (large-scale) solar power plant in Kagoshima Prefecture, Japan, in March 2014.
Daiwa Energy (Osaka City) is a subsidiary of Daiwa House Industry Co Ltd and a power producer for renewable energy-based power generation facilities. The solar power plant, "Dream Solar Kirishima Hayato," was built on the site of the former Kagoshima Plant of Daiwa House Industry in Hayato-chou, Kirishima City, Kagoshima Prefecture (See related article).
Kagoshima Plant was closed at the end of September 2009 and left idle. In an effort to effectively use the site, Daiwa Energy constructed the mega solar plant by making an investment of about ¥700 million (approx US$6.8 million).
The solar power plant is located more than 20km away from the north side of Sakurajima Island. Because the wind blows to either the east or west over Sakurajima, it hardly happens that volcanic ash is carried by the south wind and accumulates on solar panels when Sakurajima erupts. Even when volcanic ash accumulates on panels, most of it is washed away by rainwater.
However, volcanic ash sometimes remains at the lower rims of solar panels. Therefore, the chief electric engineer at the plant checks the amount of remained ash and removes it if it is highly visible.
Solar panels were installed by using "D-Tec Pile," the Daiwa House group's own construction method using steep pipe piles, instead of concrete foundations. With the method, it is possible to screw steel pipes having a relatively small aperture diameter into the solid ground.
The site of the mega-solar plant measures approximately 46,465m2. Daiwa House Industry rents the land to Daiwa Energy, which is responsible for the construction, operation and maintenance of the plant. The solar panels and PV inverters of the plant were manufactured by Sharp Corp and Toshiba Mitsubishi-Electric Industrial Systems Corp (TMEIC), respectively. The expected amount of power generated and expected sales are about 2,660,000kWh and ¥106 million, respectively, per year.