The cost of building some new nuclear plants is exceeding estimates by hundreds of millions of dollars.

Building nuclear power plants is expensive, and the costs are routinely exceeding initial estimates by billions of dollars, the Associated Press reports.

The AP’s report this week uncovered substantial cost overruns in plants in Georgia, Tennessee and South Carolina as evidence of this trend. There also have been considerable construction delays.

Plant Vogtle in eastern Georgia runs at US$800 million over its planned cost of $14 billion. Licensing delays were to blame in that instance, the AP’s Ray Henry found. Henry cited an even more egregious example: Tennessee’s Watts Bar power is $2 billion over budget. A South Carolina plant’s cost has run up $670 million.

Proponents cited in the article argued that the down economy makes building new plants less costly while others were guarded against the perception that ratepayers will view future nuclear plant builds as money pits.

New reactors are being built in rural Georgia over the next five years, and work is already underway to leap another generation ahead in technology. The industry says that the next generation of nuclear plants will be significantly safer.

Smashing atoms does require high capital costs, but proponents would note nuclear’s relatively low cost per kilowatt-hour and lack of carbon emissions. Opponents point to the high cost of subsidizing the uranium fuel cycle and some observers see the presently low cost of natural gas throwing a wrench in the works.

The Union of Concerned Scientists (UCS), which views nuclear power subsidies as a risky investment, published a report on nuclear power last year concluding that nuclear power isn’t viable without government subsidies.