BIG SUN Group, the Taiwan-based premier provider of solar energy solutions, has successfully established a presence in Japan during its campaign to introduce its latest innovations worldwide. Currently, BIG SUN is fulfilling a 5.5MW contract for a project located on Mount Akagi in Japan. This project is scheduled for grid-connection by middle of this year, and EnergyTrend is on site to find out how BIG SUN with its advanced solar tracker – iPV Tracker – has been able to successfully break into Japan and other regional markets.
BIG SUN raises the efficiency of PV power plant on the beautiful Mount Akagi
BIG SUN is the provider of system solution and technical guidance for a new PV power plant located on Mount Akagi in Gunma Prefecture, Japan. This project is owned by Nakamura Shoji Corporation and being built by Kanto Constructive Industry, while BIG SUN provides iPV Trackers and helps expedite the schedule. The plant will have a total generation capacity of 6MW, of which 5.5MW will come from iPV Trackers. Fixed-tilt PV systems will account for the rest of the generation capacity which is around 500 kW. For the first phase of the project, BIG SUN and its construction firm partner aim to finish the installation and grid connection of 2MW of solar trackers before the end of this March. Afterwards, the project will move to the second phase and 3.5MW of solar trackers are expected to be installed before this August.
Nakmura Shoji chose iPV Tracker because of firsthand experience in the system’s reliability and efficiency. Before starting the Akagi project, the company first tried out three iPV Tracker units in Saitama Prefecture. The scale of the trial then expanded to encompass 30 iPV Tracker units for another project. Seeing that iPV Tracker offers significantly higher level of efficiency and reliability, Nakamura Shoji eventually offered a contract for 680 units that make up the 5.5MW of generation capacity at the Akagi solar plant.
The model of iPV Trackers that are being deployed on Mount Akagi consists of 24 modules. Each panel has 96 mono-Si cells and its output can reach 345W, thus putting the entire solar tracker under the high efficiency category. Since the project is located on the side of the mountain, the base of individual iPV Tracker unit is secured on a concrete foundation to ensure stability.
Summer Luo, chairman of BIG SUN, was with EnergyTrend during the visit of project site. Luo and his team have offered guidance on expediting the construction process. The improvements they introduced in the building of the Akagi plant will also be incorporated into the development of future projects.
BIG SUN continuously enhances the design of iPV Tracker
Luo emphasized that the design of iPV Tracker has been modified numerous times so that the system can adapt various types of environments. The wheel axis structure has been redesigned so that it produces much less noise than before. The pulley system has also been modified to prevent the slipping of steel-wire ropes. Specific steel-wire wrappings have been introduced to the design to further reinforce the mounting structure.
“The overall basic structure of iPV Tracker is already very sturdy and refined,” said Luo. “However, we will continue to polish every detail of the system.” The steady growth in the market share of iPV Tracker shows that the constant improvements in the product has paid off.
Luo also told EnergyTrend that refinements to iPV Tracker are holistic, encompassing the base, supporting structure and mounting hardware that holds the solar panels. Hence, the panel array on iPV Tracker can incline at a wide angle while the main supporting column remain firmly secured on the foundation. At the same time, iPV Tracker can be integrated with a wide range of module types. Both the mounting and base designs aim to create flexibility so that the solar tracker can be deployed in various settings.
In the project on Mount Akagi, the bases of individual iPV Tracker units are connected to concrete foundation. This design is to maximize stability as solar trackers are perched on the mountain side. The concrete foundation also allows solar trackers to resist runoffs from heavy rain and melting snow. BIG SUN is also experimenting with other base designs and installation methods at the trial project in Saitama Prefecture. They include concrete base reinforced with steel spring cables, crisscrossing H-beams with screw-on anchor bolts and pile foundation.
“Pile foundation is the best option for hilly terrain because piles can be driven in even area with steep slopes,” explained Fritz Cheng, CEO of BIG SUN. “However, this construction method is much more expensive and is mainly suited for large-scale solar projects because more piles will lower their average installation cost. H-beam with anchor bolts would be more appropriate for smaller projects because this method is more economical as well as being one of the easiest to execute.”
In sum, iPV Tracker is highly adaptive to different types of terrain due to the ability to incorporate various designs and construction methods for its base.
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| The concrete bases on which iPV Trackers are erected in the Akagi project. |
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| A common base design is to have the system rest on top of the concrete foundation and fastened with steel spring cables. |
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| Pile foundation is effective in areas with changing slopes. |
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| These iPV Trackers have a base consists of crisscrossing H-beams with anchor bolts. |
Seeing is believing
EnergyTrend had the opportunity to see iPV Trackers in operation. In an orderly fashion, the pulley wheels at the four corners of the iPV Tracker began to rotate, tugging the steel-wire ropes and caused the module to tilt. The entire process lasted just 10 seconds and the sequence of actions gave credence to the superiority of the dual-axis mechanism.
Luo furthermore stressed that the installation of iPV Tracker is not impeded by its sophisticated design. He explained that for a single project, the EPC team only needs to assess the best location for each solar tracker and determine the most efficient angles for the device’s pulley system. The rest of the installation process is to simply follow the blueprint. Though iPV Tracker takes slightly longer time to install than traditional fixed-tilt PV systems, it is going to produce a lot more electricity once it is set up.
Mac Nakamura, director of International Development & Trade at ArchEnergy, said that his company pitted iPV Tracker against a fixed-tilt system in a trial project that was also located in Japan’s Saitama Prefecture. With the same module and inverter technologies, iPV Tracker was able to generate 44% more electricity than the fixed-tilt system could in the winter period from November 2016 to February 2017. The result of this experiment has given a big boost in confidence for both ArchEnergy and BIG SUN as they continue to hunt for opportunities on the international market.
For many years, BIG SUN has successfully demonstrated the revolutionary advantages of its iPV Tracker in trial projects worldwide. With its efforts now bearing fruits, the company is expected to soon achieve the milestone of receiving orders for 100MW-scale projects.
(Top Photo: BIG SUN Chairman Summer Luo (right) and CEO Fritz Cheng (left).)