San Francisco’s ugliest building?

Jim Herd at San Francisco Citizen nominates PG&E’s Embarcadero Substation. Here’s how he describes it:

Built in 1973, this monochromatic, cast-concrete building on Folsom Street features slightly exposed aggregate that is not detectible to the human eye from across the wide street. Discoloration from smog helps accentuate its subtle curves and makes the building read as even more massive and brawny.”