Upon exiting the Banshu-Ako JR station, we have arrived at Ako City in Western Japan. The freshness of the air is a strange yet familiar feeling. Bordering the Seto Inland Sea, the location is approximately two hours from Osaka. The rural location has preserved rustic elements of nature and culture. The Chikusa River flows past the city, once renowned as one of the cleanest rivers in all of Japan. The river’s waters are still crystal clear even today. The loyal samurai spirit of the 47 Ako Ronin protecting their master more than 300 years ago has been passed down through history in The Fall of Ako Castle, which was based on historical events……
The tireless sun is also an alluring element of Ako. Since the Edo period, Ako’s plentiful sunlight has made it famous for salt production, and the timber industry once boomed in these mountains too. The timber industry has faced a gradual decline as the times have changed and the advent of an aging society. To continue protecting these lands and contributing toward environmental sustainability, the Ako City Government has encouraged the local development of renewable energy. This has prompted some elderly timber business owners to transform ill-kept forestland to industrial use. This has facilitated the development of solar power plants, which can fully utilize the land and sun resources without placing much of a burden on nature.
As one drives across Chikusa River along National Highway 2, towards the western mountains of Ako, expansive plains are gradually replaced by green forests. Blue hills seem appear to the right as one continues on the winding mountain road. Upon closer inspection, we can see the blues hills are actually countless solar panels lining the mountainside in an enormous U-shape. The rows of blue panels vary in height according to the terrain, and are reminiscent of the waves at the Seto Inland Sea glistening under the sun… This is a large-scale solar power plant, absorbing the sun’s rays between sapphire skies and a green landscape. A large billboard notes the presence of Delta Ako Energy Park at the entrance beside the highway, and it leads us to Delta’s green energy base within the mountains—the first solar power plant solely operated by Delta Electronics.
Mr. C.H. Ko, executive director of Delta Japan (DEJ), introduced the origin of the Delta Ako Energy Park to the guests, “Ever since the tragic earthquakes and nuclear power plant accident hit eastern Japan in 2011, a well-balanced energy combination and supply system have been a major social concern. As I wondered how we could contribute to meeting this challenge with our expert knowledge and technology in power management, it came to my attention that there was a suitable location for building a mega solar plant in Ako City in western Japan.”
Delta Ako Energy Park’s opening ceremony took place on yet another brilliant sunny day. Several dozen honored guests including the DEJ team, high-level supervisors of the Delta Group, government officials, clients, and business partners gathered in the ceremonial tent near the park’s entrance. With the guidance of a priest, a traditional ceremony took place. All present appealed to the heavens and earth for peace in the harmonious, tranquil setting. Guests continued to arrive at the power plant for the ribbon-cutting ceremony of this new green energy paradise tucked away in Ako Mountain. It symbolized the beginning of a new phase as Delta’s environmental protection and energy conservation philosophies were introduced here in the form of smart technologies.
The new plant is equipped with a power generation capacity of 4.6MW, producing approximately 4,900,000kWh per year over a total area of 96,000m2. Visitors are dwarfed by the expansiveness of the grounds. It takes about an hour just to tour the facilities that sprawl across the rugged landscape. Each step we took was made possible by the hard work of the DEJ team, which has established the park from scratch over the past two years. To share their progress with Delta Group the enthusiastic team took it upon themselves to purchase an aerial drone to record the growth of the park.
After selecting the site at the beginning of 2014, the DEJ team made its first foray into land transactions, and entered into tireless communications with supervisory organizations, landowners, system integration businesses, and construction partners. First came a 3-month long land audit process, and then came approval of the land contract documents, an application for a hillside land development permit and other procedures, which over half a year’s time. The initial power plant planning and design as well as the search for suitable system integration and construction partners were also taking place. After overcoming a slew of complex regulations and protocols, DEJ finally obtained this mountain paradise at the end of the year. Once site preparation measures were completed for the park halfway through 2015, the serious business of installation, parallel network testing, and trial runs for the main solar power system finally began.
But how does one go about creating a high efficiency, easily maintained solar power system which preserves the natural terrain and the environment across a rugged hillside? Drawing on years of technical experience and after careful planning and evaluation, the team installed 17,256 solar battery modules along the uneven hillside at different angles according to the direction of optimal sun exposure. 185 medium-sized solar inverters from Delta were linked to combine advanced power control functionality and create a distributed solar PV system seldom seen in Japan. Compared to a centralized system, this system design eliminates the need for large-scale installation of big inverters and storage facilities, while allowing the power source to be dispersed and converted to improve power generation efficiency, and to reduce transformer losses from inverter failure. In addition, the team demonstrated its state-of-the-art technical potential within the industry through the innovative use of technology that boosts the 400V output voltage from medium-sized solar inverters and connects them to the extra-high voltage (33,000V) power grid.
As Mr. Ko stated, “We chose the distributed solar generation system as the best solution for not disturbing the natural shape of the land as well as maximizing power generation efficiency.”
Delta Ako Energy Park is currently the largest distributed, special high voltage solar power plant in Japan. Each year, it generates renewable energy that supplies the demand of approximately 930 local households. The power company is fully compensated for all power generated according to the regulations, and it has opened up a new business model for Delta.
The park faced the threat of flooding when a rare typhoon of exceptional strength struck Japan several months before the opening ceremony. The construction of the park was nearly complete at that point, and the well-designed disaster prevention measures and highly climate-resistant power generation system facilities endured the typhoon. However, the severity of the natural disaster reaffirmed the Delta team’s determination in slowing the progress of global warming with environmental, green energy measures. As the brilliant sun continued to shine after the storm and the opening ceremony, the park began planning additional advanced energy management, monitoring and battery energy storage system facilities in addition to supplying power for the local community and serving as a model for green energy. The new stage of this challenge is apparent, and all are anticipating Delta’s continuation as a green energy pioneer in the mountains of Ako.
