Pumped Hydro Energy Storage: It Takes A Heck of a Long Time

The most commonly used method of storing energy for the power grid is pumping water uphill and then letting the water move downhill to produce electricity when needed. It’s called pumped hydro, and like other energy storage systems, it can make the power network less volatile and help utilities avoid using expensive backup power plants. Rather than firing up last-resort plants when demand spikes, they can dispatch stored energy. But beyond the obvious fact that pumped hydro can only be implemented in hilly areas, the technology has another very serious hurdle: It spends years in regulatory and environmental review purgatory.

At a California Energy Commission conference last week, Michael DeAngelis, the manager of Advanced Renewable and Distributed Generation Technologies for the Sacramento Municipal Utility District (SMUD), discussed a 400 MW pumped hydro energy storage project called “Iowa Hill” near Placerville, Calif., that the utility is working on. The project has been under serious discussion since 2001, when SMUD started going through a relicensing process with FERC for dams and powerhouses in the Sierra Nevada region. But, according to SMUD documents, the site has been under consideration for pumped hydro “on and off since 1972, when Bechtel Corp. performed preliminary engineering on the Iowa Hill site.” DeAngelis said last week that if construction starts on the project this year, the best estimate for when it would start operating is 2015.


Between serious discussions and production, that’s over a decade. And that’s almost 40 years from basic concept to completion. At that rate, we can just wait for global warming to take effect before adding the crucial capacity of energy storage to the power grid. To be fair, as Better Place’s Sven Thesen pointed out at a recent energy storage conference, there are some really serious environmental implications of pumping water up and down mountains. But decades? Startups, start looking into alternatives like these eight technologies and this one that just uses a heat pump and gravel.