I don't think it's about the efficiency, it's about managing waste. Currently, a lot of hydro generation is wasted at nighttime because there is less demand, so

I don't think it's about the efficiency, it's about managing waste. Currently, a lot of hydro generation is wasted at nighttime because there is less demand, so it's burnt off. Even if inefficient, it would be better to shift this energy to somewhere where it isn't night time