Most pumped hydro is short-ish term storage and at full capacity runs from full to empty within 10-20 hours. And in a new development there's nothing really sto

Most pumped hydro is short-ish term storage and at full capacity runs from full to empty within 10-20 hours. And in a new development there's nothing really stopping you from putting in more pipes and generators so you can get the full energy out in half the time if that makes more economic sense. Conceptually they are like batteries, just with the ability to scale max discharge rate and max capacity somewhat independently, a much lower cost per MWh stored, but high engineering complexity because each site needs a bespoke solution. Of course there are some projects that just go for huge storage and few generators. Sometimes they serve another purpose and just have generators as a side benefit. And sometimes they don't make a lot of sense and seem to just be built that way to be more impressive