Brian,
Your right, stacking is not critical, any would be based on design and operations considerations. In major urban areas, might be economical….. but you’d need to get the plant permitted first….you know my opinion about that.
Aeronaut,
Example, the switchyard on a 1.7Gw plant I’ve drawings for is a square about 700′ on a side. I’d imagine that there would be some economies of scale for large plants, but remember, high voltages require greater separation, hence more size.
As for transmission design, I’ve no experience with it. I’m an M.E., you need to ask that one of a double E.
Rematog