This is an update on June 4, 2020.
Since we figured out the Hitachinaka Kyodo No.1 (Hitachinaka Generation, Ibaraki, 650 MW) started trial operation in March, we updated our data.
Now, the number of units under operation (including trial operation) is 17.
Please see the web for detail. https://sekitan.jp/plant-map/en/v2