ATLANTA | New suppliers will be making parts for a nuclear power plant under construction in Georgia, a development that comes after a factory struggled to deliver parts on time, a monitor for state utility regulators said Tuesday.

Nuclear engineer William Jacobs Jr. said he learned this spring that two new vendors, Oregon Iron Works and SMCI, will construct large parts needed for brand-new nuclear reactors at Plant Vogtle. That facility and an identical plant under construction in South Carolina are the first new nuclear plants built in the United States in a generation.

A factory owned by CB&I in Lake Charles, Louisiana, was producing large structural modules, some weighting tens of tons, that could be picked up by a crane and hoisted into place. The technique was supposed to be faster and cheaper than building a plant part-by-part at the construction site.

However, the CB&I facility has struggled to produce the modules while meeting the detailed quality control rules required for the nuclear industry. Jacobs wrote in a recent report that the factory was “not prepared for the rigor of nuclear construction.”

“Certainly there have been problems at Lake Charles getting the modules, so I guess it’s not totally surprising that the consortium would go ahead and look around,” Jacobs said during a hearing at Georgia’s Public Service Commission. CB&I spokeswoman Gentry Brann declined to comment, referring questions back to Georgia Power.

Jacobs said Georgia Power has increased its oversight over suppliers to address quality issues.

While the factory in Lake Charles will continue producing smaller parts, Westinghouse Electric Co. and CB&I are steering larger work to other firms. For example, it earlier contracted with Newport News Industrial Corp. in Virginia to construct pieces that will form a protective wall around the heart of the reactors.

The entire construction project was originally supposed to cost roughly $14 billion, though that figure is likely to climb. Southern Co. subsidiary Georgia Power, which owns a 46 percent stake in Plant Vogtle, estimates its construction spending is tracking $646 million above its $6.1 billion budget. Since Georgia Power is a regulated monopoly, its customers will pay for the construction costs unless elected regulators intervene.

Financial analysts for the state still calculate that finishing the nuclear plant is a better economic deal than building gas-fired power plants instead.

The other project owners include Oglethorpe Power Corp., the Municipal Electric Authority of Georgia and the city of Dalton.