PG&E Grid-Scale Storage Demo Projects

PG&E does have another pumped hydro site in development, Mokelumne, that's potentially the same size as Helms and has the potential to be used to help buffer the 4,500 megawatts of wind power coming in from the Tehachapi wind developments. So, PG&E understands pumped hydro.
Electrochemical storage might be a different story.
PG&E has two pilot projects using sodium sulfur (NaS) batteries from NGK. NGK's NaS batteries were selected because they are one of the few technologies and vendors with a performance and reliability track record. According to Thalman, the pilot can help the ISO develop the storage markets with this testbed.
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