Heretic of The Seventh Circle
This is largely irrelevant when discussion city-wide power grid infrastructure, rather than the powering of a single (not super common) building.Unfortunately, you hit a surface area/volume ratio issue.
A building's ability to generate solar energy scales with its surface area.
A building's consumption of energy scales like it volume.
So, the bigger the building, the less it is able to provide energy for itself.
A given building’s power generation is just part of the city’s power supply. Mitigating how much a very large building sucks out of the grid is worthwhile up to very large buildings, and there are other solutions being used and developed for the largest structures which can take over in those rather uncommon cases.
The vast majority of urban centers don’t have many (if any) skyscrapers or massive super warehouses. They do have vast swathes of exposed roadway and parking lots.
And the advantage goes to city solar in terms of ecological impact, as well, as exposed asphalt and concrete causes cities to be dramatically hotter than surrounding countryside, while covering a desert in panels would inevitably cause massive damage to the desert ecology.
One aspect I’m not versed in at all is moving power over a distance. Idk how much inefficiency is caused by having the power generator miles away from the power usage.