(The Center Square) — Units 3 and 4 of Georgia Power's Plant Vogtle are the only new nuclear reactors built in the U.S. in decades, and a new report is cautioning states not to follow Georgia's approach.

Officials traveled to Plant Vogtle, located along the Savannah River in Burke County, south of Augusta, on Wednesday to celebrate the new reactors' opening. However, the project has been met by critics who say the $35 billion project is a "cautionary tale" for future nuclear construction.

Six Georgia groups — Center for a Sustainable Coast, Concerned Ratepayers of Georgia, Cool Planet Solutions, GCV Education Fund, Georgia Wand and Nuclear Watch South — have commissioned a new report, "Plant Vogtle: the True Cost of Nuclear Power in the United States."

"There are real people paying for Plant Vogtle, people who cannot afford the resulting high electric bills that should never have happened," the report concluded. "The authors of this report urge other states not to follow in Georgia's footsteps."

"Plant Vogtle points to the failure of the State of Georgia generally, and the Georgia Public Service Commission specifically, in protecting its people from monopoly utility power and overreach," the report added. "Plant Vogtle would never have happened in a competitive business environment, and should not have happened in the Georgia regulatory environment which was created to protect the public interest from monopoly abuse."

According to officials, Georgia Power expected to spend more than $10.7 billion on Units 3 and 4, higher than a nearly $7.3 billion estimate the PSC previously deemed "reasonable."

Georgia Power has indicated that "average retail rates" would increase by roughly 5%, and "a typical resident customer using 1,000 kWh per month" could see their monthly bill rise by $8.95. However, the groups point to a Georgia Center for Energy Solutions finding that average monthly residential bills for Georgia Power ratepayers have risen by $35 since Units 3 and 4 came online.

The groups point to Georgia Power executives' statements in 2009 at the start of construction, saying Vogtle 3 and 4 would be on time and budget. Adding to complications during construction, Westinghouse, the main contractor and designer of the AP1000 reactors, declared bankruptcy.

"Plant Vogtle represents an incredible feat of ingenuity, partnership and technological innovation," House Speaker Jon Burns, R-Newington, said in a statement. "The successful completion of this project will provide Georgia families and businesses with clean, safe, reliable and affordable energy for generations to come."

Georgia Power owns nearly half (45.7%) of Plant Vogtle. Oglethorpe Power Corporation, which serves 38 electric membership corporations across Georgia, owns 30%, while the Municipal Electric Authority of Georgia owns 22.7%, and Dalton Utilities owns 1.6%.

In an email exchange with The Center Square, Tim Echols, vice-chairman of the Georgia Public Service Commission, said "a federal backstop" is the only way "to be protected in the future."

"Georgia is seventh in the nation in utility-scale solar, but most of that represents an energy asset only — not capacity," Echols said. "Nuclear gives us carbon-free baseload, and we paid the learning curve for all of America to experience it much like California did with solar.

"Critics want to close coal and gas plants, and then complain about the cost of clean technology," Echols added. "You can't have it both ways."