Environmental groups and nuclear critics say TVA and other utilities should spend their money on energy efficiency programs and renewable resources such as solar.
Although nuclear plants don't produce GHG emissions, storing nuclear waste remains a challenge, because it takes millions of years to stop being radioactive. Further, should something catastrophic happen, generations could be affected.
TVA expects to spend between $4 billion and $4.5 billion on the 2nd Watts Bar reactor — nearly double earlier estimates. A TVA inspector general report in 2012 concluded that the project was first set for completion that year at a cost of about $2.5 billion.
For comparison, TVA this month announced plans to shutter its Allen coal-fired power plant near Memphis and instead build a natural gas facility. That gas plant is expected to cost $975 million and produce 1,000 MW of electricity, enough to power 580,000 homes. TVA officials say both projects are smart investments.
Meanwhile, as part of the Watts Bar project and to meet new Nuclear Regulatory Commission safety rules in the wake of the Fukushima Daiichi nuclear disaster in Japan in 2011, TVA built a separate building to house emergency response equipment.
The building is designed to withstand tornadoes, earthquakes and more. Inside, diesel-powered generators and pumps are ready in the event the site loses power and TVA must keep the reactors cool. Watts Bar is expected to be one of the first nuclear plants in the nation to complete its Fukushima safety upgrades.
The cost and complexity show why nuclear isn't a good investment for TVA and other utilities, said Stephen Smith, executive director of the Knoxville-based Southern Alliance for Clean Energy. "TVA is representing that this is going to be the 1st new nuclear plant in the 21st century. They are counting how it is on budget and on schedule," he said. "But you have to have amnesia to really buy into that." TVA's ratepayers have been paying for Watts Bar 2 since the early 1970s, but haven't yet received any electricity from it, Smith said.
"It is a magnificent feat of engineering, no doubt about it," Smith said. "Is it a good investment? I question it."
The Proverbial Eggs
Still, TVA officials remain confident that nuclear energy has a bright future. In addition to the Watts Bar reactor, TVA is actively researching the possibility of deploying what are known as small modular reactors. They are cheaper and produce about 180 MW of electricity.
Skaggs, TVA's senior vice president for nuclear operations, said the utility strives for a balanced portfolio of energy sources and that nuclear remains an important part. Nuclear accounts for just over 1/3 of TVA's energy.
"We don't want to put all of the proverbial eggs in one basket," he said in an interview from a construction trailer in the shadows of Watts Bar's two 535-foot-tall cooling towers.
TVA officials said nuclear energy is safe and reliable. The decision to finish Watts Bar is based on the need for "carbon-free, baseload power," spokesman Scott Brooks said. "Unit 2 is an investment in that demand for at least 40 years to come."
But Brooks said TVA isn't investing in nuclear beyond Watts Bar, without "more serious consideration of future demand." As for the cost, Brooks said that while the estimate was revised upward in early 2012, the project remains on time and budget.
Skaggs said the 2nd Watts Bar unit will require fewer resources to operate, because many workers already on site can easily operate both units. He said building the plant must be done right.