Visit to Plant

Solar Plant Built Through Japan's 1st 'Recruiting Process' (page 2)

Frequent lightning interrupts remote monitoring

2019/11/11 19:34
Shinichi Kato, Nikkei BP Intelligence Group, CleanTech Labo
Print Page

'Joetsu mainline' enhanced through bids

This mega-solar plant is situated about 660m above sea level. The peaks of Mt. Tanigawa and other mountains in the Joshinetsu region can be seen from around the power plant. With vegetable fields and mountain forests spreading across the surrounding area, it gives the impression as if being in Hokkaido (Fig. 2).

Fig. 2: The plant in located on a plateau. (source: Nikkei BP)

Showa Village boasts farming and abundant sunshine. Given the high altitude, the temperature is relatively low even in mid-summer, and it means the output of crystal silicon-type solar panels, which see power generation efficiency decline during high temperatures, is not likely to decrease even in summer.

Given these circumstances, the area is suitable for solar power generation. Accordingly, many solar panels are arrayed in fields and between the mountain forests in the surrounding area.

The Sun-Farm Sennennomori initially began operation with a solar panel capacity of about 2.419MW and a grid capacity of 1.99MW in November 2013 (Fig. 3). Comsys Create calls this phase 1 project "site A." Generated power is sold at 40 yen/kWh (excluding tax) based on the feed-in tariff (FIT) scheme.

Fig. 3: Outlines of site A (top), sites B and C (bottom) (source: Comsys Create)

Two phase 2 mega-solar projects began operation in the adjoining site later in October 2017, almost four years after the phase 1 project started selling power. These phase 2 projects are called site B and site C. Generated power is sold at the FIT-based unit price of 36 yen/kWh (excluding tax).

Combining the two phase 2 projects, the solar panel and grid capacities are about 3.920MW and 3.240MW, combining about 2.305MW and 1.99MW at site B and about 1.616MW and 1.25MW at site C, respectively.

TMEIC PV inverters were adopted at all the three sites while solar panels of Sharp are used at site A and those of Kyocera Corp at sites B and C. Steel- and concrete-type foundations and mounting systems were adopted at site A while pile foundations and aluminum mounting systems were adopted at sites B and C. Cost efficiency is higher in the latter (Fig. 4).

Fig. 4: Foundations and mounting systems at site A (top) and B, C (bottom) (source: Nikkei BP)

Sites B and C obtained the right to grid connection through "Japan's first recruiting process (bids for enhancing the grid capacity)" conducted by Tokyo Electric Power Co Holdings Inc.