Giant smoke ring hovering over College Station causes stir

A smoke ring rises over College Station after an explosion July 25, 2013. (Laura Woods via Twitter) A smoke ring rises over College Station after an explosion July 25, 2013. (Laura Woods via Twitter) Image 1 of / 3 Caption Close Giant smoke ring hovering over College Station causes stir 1 / 3 Back to Gallery

A blown transformer in College Station on Thursday caused a lingering smoke ring in the evening sky.

The transformer, housed in a substation in southern College Station, blew up at 8:20 p.m., causing about 3,000 customers in that city to lose power, said Carol Roach, spokeswoman for College Station Utilities.

The substation is shared with neighboring Bryan Texas Utilities, which owns the current transformer that failed, said that utility's spokesman, Paul Buckner.

"There's oil inside that transformer, and that's what caught on fire," Buckner said. "We are still investigating the cause."

None of Bryan Texas Utilities' customers lost power, he said.

When the transformer exploded, however, it triggered a protective feature in the College Station system that resulted in a power loss for the 3,000 affected customers, similar to the way a surge protector works in a home, Roach said.

College Station's power was restored at 9:12 p.m., she said.

"We had to make sure that everything was in the clear before we could restore the power," Roach said.