According to a report from the California Independent System Operator, reliability could be "marginally more challenging" in San Diego and southern Orange counties since the San Onofre nuclear power plant has been shut down since last year.
The plant is the largest source of electricity in Southern California, capable of powering 1.4 million homes.
During peak periods, residents in southern Orange County and San Diego counties may be asked to conserve to help out with "rapidly changing grid conditions," officials said.
But under normal summer conditions, the report states that there is an adequate supply of electricity resources.
Southern California Edison has asked the Nuclear Regulatory Commission for permission to restart the plant, but a decision is not expected until next month.
The Associated Press contributed to this report.
