TVA Considers Building Two Small Modular Reactors

At Old Clinch River Breeder Reactor Site

The Tennessee Valley Authority is working with Babcock & Wilcox and Bechtel Corporation to test a pilot small modular reactor (SMR) known as mPower.  Aided by up to $150 million of funding support from the U.S. Department of Energy, TVA and its nuclear contractor partners have agreed to be the first to test the mPower design and to submit plans for regulatory approval by next year to build a pair of the new reactors on the Clinch River in Oak Ridge.

TVA is planning to build two 180-megawatt small modular reactors on the Clinch River in Oak Ridge. Rendering by Babcock & Wilcox Nuclear Energy

If approved by regulators and the TVA board, the new 180-megawatt reactors could be producing enough power for all the energy needs of Oak Ridge by 2022.
Developers hope the smaller and simpler design will allow for factory fabrication of most plant components. The simpler and passive cooling design also should allow for reactors to be located underground and to be built quicker and with less cost.

Small modular reactors also offer the prospect of adding nuclear generation in incremental stages with less one-time capital costs than the current generation of nuclear plants.  The new small modular nuclear reactors may be built in a factory and shipped to the Tennessee Valley in a truck or railcar.

In response to DOE's funding offer to support new small modular reactors, four applicants applied to build one of the new smaller reactors. So far, the consortium between TVA, B&W and Bechtel is the only one picked by DOE for the government assistance. TVA and B&W are scheduled to file an application for two of the mPower units by mid 2014, and the U.S. Nuclear Regulatory Commission is expected to decide on the request the next year.

The proposed small modular reactor designed by Babcok and Wilcox would rely upon a passive cooling system with water supplies above the reactor so that in an accident water could flood the reactor core without having to rely upon so many pumps, valves and pipes. The smaller design also could allow major components to be made in the factory and shipped to the site by truck or rail, rather than having to build the much larger and complex plants at the site.

The mPower units could help TVA meet future power demand growth and make up for the planned closing of more aging coal-fired power plants.  The reactors for SMRs are buried in the ground and it's almost impossible to uncover the core in this design. So they have some inherent safety advantages.

TVA is focusing its nuclear attention right now on finishing the Unit 2 reactor at Watts Bar by 2014 -- nearly 40 years after work on the unit first began.

TVA is looking at building the reactors on the site of the Clinch River Breeder Reactor that former President Jimmy Carter scrapped in the 1970s.  (Times Free Press, 6/2/2013)