Southern Co. forecasts it will exceed its $6.1 billion budget while building a new nuclear plant in eastern Georgia.

The Atlanta-based utility said Friday that it now expects building two more nuclear reactors at Plant Vogtle (VOH’-gohl) near Augusta will cost roughly $6.2 billion, a slight increase. Those estimates are subject to change.

Vogtle is the first nuclear plant approved for construction in a generation. It’s being watched closely to see if a power industry plagued by cost overruns in past decades can build a nuclear plant without busting budgets. Southern Co. said finishing the nuclear plant remains a better deal than other alternatives.

Georgia’s Public Service Commission must approve all spending on the project before the utility can charge its customers for the work.