じゅん揚水 ようすい発電 はつでんではありませんでした
jun'yo usui hatsudendewārimasendeshita

Noun
Desu Copula

The polite, past negative form of 純揚水発電

1. Was not pure pumped-storage hydroelectric power.

Past/Perfective
Negative
Polite
Formal Register