I believe I found the answer. Wikipedia says the car house was demolished in 1983.
Photo below:
"San Francisco Muni's former Geneva Car Barn, from its northeast corner, on September 19, 1982, which was the last day that streetcars operated in service from it.
"It stored some PCC cars for about two months more, before it was demolished in January 1983 – leaving only the office building and power house at the corner of San Jose & Geneva Avenues still standing."