Visit to Plant

Japan's Largest Solar Plant Withstands Ash, Salt, Strong Wind (page 4)

Widespread effort to realize 70MW output, finish construction in 14 months

2013/12/01 19:56
Shinichi Kato, Nikkei BP CleanTech Institute
Print Page

Foundation measures to shorten construction period

Construction was carried out in series from the seaside to the landside, dividing the 36 2MW blocks measuring about 210 x 110m each into six zones. Efforts were also made in this phase to shorten the construction period.

One of those efforts was the way the foundations were built. A "direct finish" method was deployed in which concrete was poured from cement mixer trucks into a mold and the foundations were completed without post processing. This method is suitable to reduce the time to build the foundations. Cement mixer trucks could navigate the 3.5m space between solar panels and directly pour cement into the mold.

Using metal molds, the foundation could be made in a shorter period of time without specialist workers (Fig. 7). There was a cost involved to create the molds, but the cost increase was minimized by making 37,660 foundations one by one using the same molds. In the conventional method, the foundations would be made by pouring concrete into wooden molds assembled on site by specialist workers.

This metal mold also eliminated the previous need for specialist workers to install reinforcing bars because it enabled the foundation to integrate reinforcing bars with concrete just by setting the bars in the foundation when it is made. Moreover, this mold can be set with a rain cover similar to a tent so the foundations can be laid even on rainy days.