One of two nuclear reactors at Plant Vogtle near Waynesboro, Ga. unexpectedly shut down Wednesday, but officials said the reactor should be up and running Saturday.

No problems were reported with the automatic shutdown, which occurred because of the operation of a breaker that allows the control rods in a reactor to drop, said Steve Jackson, vice president of power supply at the Municipal Electric Cities of Georgia (MEAG). Control rods are used to vary the output power of a nuclear reactor, according to the U.S. Nuclear Regulatory Commission.

Covington is a member of MEAG and receives nuclear power from Plant Vogtle. Georgia Power also receives power from Plant Vogtle. Covington Utility Director Bill Meecham said the outage should have very little affect on local power capacity or cost. Power usage is lower during the spring and excess power is readily available, he said.

Nuclear reactors are designed to shut down if automatic monitoring systems detect conditions that could be unsafe, and these unexpected shutdowns occasionally happen each year.

Nuclear Regulatory Commission and utility officials say there have been no leaks, damage or other safety concerns reported, but officials are still trying to determine what prompted the shut down.

"This occurrence shows how systems are supposed to work to shut a unit down when a problem is detected," said Paul Warfel, senior regional manager with MEAG.

The Associated Press contributed to this story.