Tom, I’m sure you already have a packed schedule but since you are in the Southeast already consider a side trip to McIntosh Alabama to do a video on the CAES (compressed air energy storage) facility there.  It would tie in nicely with the one you did on the Dinorwig power station.  The CAES releases over 100KG of air <b>per second</b> when operating in energy recovery mode, and it can sustain that rate for 7 hours.  They use some clever air-to-air heat exchangers to further increase efficiency.