The carbon-free power comes at a high price

The second of two new nuclear reactors in Georgia has entered commercial operation, capping a project that cost billions more and took years longer than originally projected.

Georgia Power Co. and fellow owners announced the milestone Monday for Plant Vogtle's Unit 4, which joins an earlier new reactor southeast of Augusta in splitting atoms to make carbon-free electricity.

Unit 3 began commercial operation last summer, joining two older reactors that have stood on the site for decades. They're the first two nuclear reactors built in the United States in decades.