ATLANTA— The state agency that regulates utilities could decide next week whether to complete two new nuclear reactors at Plant Vogtle or cancel the project that’s been plagued by delays and escalating costs.

Georgia Power estimates the reactors will cost $12.2 billion and won’t be finished until 2021 and 2022. The new reactors on the Savannah River near Waynesboro were initially expected to cost the company about $6 billion and be completed this year.

The state Public Service Commission has to decide whether the reactors are still a good deal for ratepayers, who would bear much of the cost. The PSC’s analysts say it’s not, arguing the project’s current price tag is $3.9 billion more than what they consider reasonable.

A vote by the PSC on whether to move forward was expected in February. But commissioners on Monday agreed to move their vote to Dec. 21. PSC Chairman Stan Wise said Georgia Power wants a decision now so that, if the project gets canceled, the company could take advantage of tax laws that Congress plans to change next year.