Dive Brief:

Tennessee Valley Authority (TVA) will soon be the first U.S. utility to get permission to potentially build and operate small modular reactors (SMR), after the Nuclear Regulatory Commission authorized the issuance of an Early Site Permit for the utility's Clinch River site.

The reactors, which have yet to be approved by NRC, are being touted by supporters as a key tool to help the U.S. and other countries decarbonize their power sectors, but some are questioning the course NRC has taken with yesterday's actions.

TVA said it has no plans to build such a reactor, but the permit "will give [it] flexible options to prepare for future energy needs." The commission announced the permit on Tuesday and proposed emergency planning requirements for SMRs.

Dive Insight:

The commission expects the Early Site Permit to be issued in the next few days. It will be good for 20 years and allows for a nuclear facility at the Clinch River site near Oak Ridge, Tenn. with a capacity up to 800 megawatts.

“The early site permit is a significant step in the potential development of small modular reactor technology,” Dan Stout, director of nuclear technology innovation at TVA, said in a statement.

TVA applied for the permit in 2016, addressing site safety, environmental and emergency preparedness requirements, and NRC began its formal review in January 2017.

The utility now has until 2039, with the possibility of an extension, to decide whether to go ahead and pursue construction of small modular reactors. "Another NRC application is required to build and operate this kind of facility," TVA noted.

“The decision to build will be based on energy needs and economic factors” TVA Chief Nuclear Officer Tim Rausch said in a statement.

“SMRs are more attractive where load growth is slow, and they provide a more affordable option than the higher up-front capital costs associated with larger nuclear facilities,” Stout added.

In addition to approving the Early Site Permit for Clinch River, NRC yesterday issued a proposed rule for public comment on emergency preparedness requirements for SMRs.

These requirements have focused mainly on large light water reactors — the primary type of reactor operating in the U.S. today. With its proposed rule and related guidance, NRC said it is updating the emergency requirements while considering advances in reactor design and safety research.

"The alternative requirements would include a scalable approach for determining the size of the emergency planning zone around each facility, based on the distance at which possible radiation doses could require protective actions," the commission said.

The Nuclear Energy Institute (NEI) called the NRC actions "a major milestone."

“By revising its process for establishing the size of the emergency planning zone [EPZ] based on the type of advanced reactor developed, the NRC is demonstrating its commitment to evolving regulations, so they align with the size and inherent safety features of advanced nuclear technologies," NEI Chief Nuclear Officer Doug True said in a statement.

According to NEI, "the 10-mile EPZ in use for existing plants was established 40 years ago; since then, there has been additional research and enhanced understanding of the safety benefits of advanced reactor designs."

But while SMRs are seen by the nuclear industry and other supporters as a safer, more economical option that can propel the sector into the decades ahead, there are considerable misgivings about the NRC's actions.

"The NRC has made a big mistake in issuing these deeply flawed and reckless decisions," Edwin Lyman, senior scientist at the Union of Concerned Scientists, told Utility Dive via email. "The exemptions to current emergency planning regulations granted by the Commission to TVA authorize the elimination of critical components of nuclear safety."

According to Lyman, NRC's actions could allow TVA to "build and operate new nuclear reactors without having to develop off-site emergency plans, based on little more than highly uncertain paper calculations of radiation risk for reactors that have never before been built or tested."

In addition, its proposed emergency preparedness rule "would institutionalize these dangerous exemptions for any new applicant for small modular reactors or reactors using technologies different than the existing fleet."

And SMRs are getting closer to being approved in the U.S.

Reactor developer NuScale announced Dec. 12 that NRC has finished Phase 4 of its review of the design certification application for its SMR, "representing the completion of the advanced safety evaluation report." The assessment is now in its last two phases and the "NRC remains on track to complete its final review of NuScale’s design by" September 2020, NuScale said.

NRC said it will soon publish its proposed emergency preparedness rule in the Federal Register and accept comments for 75 days after that.