An electrical outage that occurred Tuesday night was caused by equipment failure at Lower Valley Energy.

“It was no act of nature,” Lower Valley spokesman Brian Tanabe said. “It was just a pure hardware failure. We had a relay go bad, and it resulted in the outage.”

The hour-long lapse of electricity zapped power at businesses and houses in west Jackson and along Spring Gulch Road.

About 900 Lower Valley Energy customers were affected from 7 p.m. to 8 p.m., Tanabe said.

Lower Valley averages about 300 outages a year, a number Tanabe said is not high.

“When you look at frequency of outages and duration of outages for utilities of our size, we are very good,” he said in an email.