Do you have a reference for the hydroelectric storage number? Does this include hydroelectric dams without reverse-pumping capability, which still do have the capacity to perform fast grid leveling?
Re:Cash Squeeze at Tesla, SolarCity
by semi-extrinsic on Friday September 02, 2016 @04:00AM
(#12411620)
https://en.m.wikipedia.org/wiki/Pumped-storage_hydroelectric...
I believe this number only includes dams with reverse pumping. The global production capacity for all hydroelectric power is much larger, but it's not a widely used number, since you typically don't empty a reservoir due to the lower water having less potential energy.
So this capacity number is a bit theoretical, since you wouldn't use it that way in practice. But then again, so is the capacity number for batteries, since you really want to avoid doing a full discharge.
Annual global hydroelectric production is a more useful number, and is a little more than 4 000 TWh.
Cool, thanks. I wasn't aware that pumped hydroelectric had this great installed capacity. Those are very big numbers. Of course, it isn't an either/or proposition, since pumped hydroelectric is limited by geography. Battery-supported grid levelling can also be installed locally at each residential solar project, which makes adoption less of a political case.
Re:Cash Squeeze at Tesla, SolarCity
by greglindahl on Friday September 02, 2016 @03:15PM
(#12415489)
These things all have different growth rates. You might want to mention those, too.
For further comparison, the total capacity of existing pumped hydroelectric storage plants is 740 000 GWh. (This puts plans of battery-based electricity storage in a rather harsh perspective.)