Georgia Power's portion of the nuclear expansion project at Plant Vogtle near Waynesboro is tracking about $28 million under budget, the utility's latest construction report says.

The twin 1,100-megawatt reactors might not start producing electricity until late November 2016 and 2017, however, because federal regulators issued a key construction license in February, later than the utility expected. The reactors were scheduled to start producing electricity in April 2016 and 2017. Georgia Power has not yet decided whether it will consider changing the construction schedule to meet that schedule, the report said.

The company said it would not sacrifice safety or quality to speed up the construction schedule, according to the report.

Georgia Power is part of a group of utilities building two $14 billion reactors at Plant Vogtle. The utility is responsible for $6.1 billion of the project. It must file a construction and scheduling report with the state Public Service Commission every six months. The PSC has not required the other utilities to file separate reports because they are municipal and cooperative utilities and are not regulated by the agency.

Customers already are paying down the project's financing costs through a controversial fee in their monthly utility bills. Georgia Power officials have said that plus the potential of receiving production tax credits and taxpayer-backed federal loan guarantees will help save customers $1 billion in the long run.

The report, filed late Tuesday, covers July 1, 2011 through Dec. 31, 2011. Georgia Power has spent a little more than $2 billion on the project so far, according to the document, which warns that project costs will go up as the reactors are built. The costs could be related to previously made changes to the reactor design, scheduling delays or other so-called change orders.

Georgia Power currently is negotiating with the other utilities to determine who is responsible for such changes. If Georgia Power is responsible, the utility can pass those costs onto customers.