Ibiden's Floating Solar Mounting System Features High Stability (1)
High-density polyethylene filled with foamed material
A floating mega (large-scale) solar power plant featuring an output of 1.99MW was constructed on a pond at the former site of a lumberyard in Takahama City, Aichi Prefecture (Fig. 1).
The mega solar power plant is on the site of the Kinuura Plant of Ibiden Co Ltd, which is engaged in the production of printed circuit boards and semiconductor package materials as well as the hydraulic power generation business. The power plant started operation in February 2016. The power producer is Ibiden Engineering Co Ltd, which is a subsidiary of Ibiden Co Ltd and is based in Ogaki City, Gifu Prefecture.
Ibiden Engineering is in charge of the designing and construction of power equipment and plants in the Ibiden Group. In its power equipment business, the company also designs and constructs gas turbines and solar power generation systems, utilizing the knowledge of Ibiden obtained through its hydraulic power generation business.
The company started the power sale business by constructing solar power plants and small hydraulic power plants after implementation of the feed-in tariff (FIT) scheme targeting renewable energies.
Apple Inc of the US, to which Ibiden delivers semiconductor package products, announced recently that "Ibiden pledges that it will realize 100% renewable energy use in the production of products intended for Apple," which attracted considerable attention. Nearly all the renewable energies consumed by the Ibiden Group are generated by Ibiden Engineering.
In developing the floating mega solar power plant on the pond at the former lumberyard site in the Kinuura Plant, the company gave careful consideration to floats that are used to support solar panels and combiner boxes on the water surface, among others.
When the company began to look into using floats, few were on the market, and floating solar power plants in Japan incorporated floats made by foreign manufacturers that introduced the products to the market at an early stage. Floats that are made of high-density polyethylene and are hollow were linked together for use.
One of the advantages of Ibiden, which has been engaged in the hydraulic power generation business for many years, is that the company has wide-ranging knowledge on the safety and reliability required for the power generation business, according to Shuso Mizumoto, managing director of Ibiden Engineering. Based on the experiences of the company, floats made by foreign manufacturers did not seem to ensure the stability, safety and long-term reliability of power generation equipment, Mizumoto said.
When the pond is subjected to strong winds from typhoons, for example, there was a risk of an accident caused by floats, and the attached solar panels, on the edges of the plant rising up. Because the floats are hollow, the level of stability that the company expected for installation and maintenance, when workers walk or work on them, was not realized, either.
Because the company could not find any suitable product in the market, it decided to develop its own floats. The products are also used in the EPC (engineering, procurement and construction) services that the company offers, as well as the company's own floating mega solar power plants.