Georgia Power fell farther behind last year on building two new nuclear reactors near Augusta, but the utility expects to catch up and complete the nearly $15 billion project on the same schedule it projected last year.

In an update to regulators Friday, Georgia Power also indicated that it expects the expansion to cost $14.8 billion, down from a year-ago projection of $15 billion.

The massive project, the nation’s first new nuclear construction in more than 30 years, will more than double the generating capacity of Plant Vogtle, from two nuclear reactors to four.

Despite the reduction in the total cost estimate and Georgia Power’s assurances that both reactors will still open by late 2018, the project is about 19 months behind the original timetable and several hundred million dollars over the original budget.

“It’s good news and bad news,” said Liz Coyle, with Georgia Watch. Coyle, acting executive director of the consumer advocacy group, said the project’s prospects haven’t worsened, but it remains over budget and behind schedule and will saddle Georgia’s customers with far more power generation capacity than the state needs.

Georgia Power argues the expanded nuclear plant will save customers billions of dollars over its 60-year life-span through lower fuel costs and other savings.

In Friday’s filing with the state Public Service Commission, Georgia Power said its contractors completed $389 million worth of construction last year. That was less than the $560 million worth of construction the utility had expected to complete.

But Georgia Power said it is making up lost time. The company partly credited “key leadership changes” after one of its contractors was acquired a year ago. Georgia Power said it has “seen overall improvement in the contractor’s transparency, cooperation and communication as well as execution with a focus on quality and schedule.”

Georgia Power and some of its contractors have been mired in lawsuits over $400 million in damages related to cost overruns and delays.

A Georgia Power official said the company it is completing work on the second new reactor more quickly than expected. That is contributing to the downtick in cost estimates, as are savings from financing costs that are forecast to be about $91 million lower than previously projected.

That should allow the nuclear plant builders to catch up, said Buzz Miller, Georgia Power’s executive vice president of nuclear power development.

“It’s still a good deal, and getting better,” he said.

Friday’s filing also showed that since 2009, customers have paid $438 million through surcharges on their monthly bills — typically about $5-7 a month for the typical customer — to help finance the project.

The PSC approved starting the surcharges before work is done after Georgia Power argued they will ultimately save ratepayers hundreds of millions of dollars over the life of the power plant.