Get as techy as you like! I can just about keep up on a Sunday! My understanding for the placement (but obviously I can`t vouch for its authenticity) was ToT and RnR share the same substation / feed / juice source, separate from the rest of the park, since if both drop shafts went to maximum draw on the studios grid simultaneously, plus RnR launched at the same time, at best there could be a brown out, at worst a failure. Hence they share a separate power source from the rest of the park.
Ahhh.. the Central Energy Plant. The original 1971 plant in the North Service area. When EPCOT Center was built they constructed a substation for the park, backstage east of what is now Mission:Space. Another of my useless bits of trivia (I even have the photo...)
Since we are on the subject, does anyone know what ratio WDW makes its own power to what is bought in from outside? I know originally it was self sufficent (MK, North Services, East Services, tree farm & sewerage, 2 hotels, Seven Seas monorial & the Village area) but I doubt they can sustain todays demand. I do believe, however (again) that WDW can sustain itself for emmergency power in a blackout if need be. Park power failures have been due to technical failures / storm damage, not lack of jiuce. Can anyone clarify this?