4c524e74_y_Storage____Clean_Energy_Wonk__1
[0] Regenerative Fuel Cell (Hydrogen) [2] First pilot project 2004 [3] “much less” than 80% [4] Fuel cell manufactures: Ballard, FCEL, and others. [1] 
Fuel cells can be run in reverse for electrolysis, with the hydrogen stored in large tanks.
Large Scale Electricity Storage. | Clean Energy Wonk
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