Study confirms NuScale reactor's MOX capability

21 January 2016

NuScale Power's small modular reactor (SMR) has the capability of using mixed uranium-plutonium oxide (MOX) fuel in addition to conventional light water reactor fuel, a study by the UK's National Nuclear Laboratory (NNL) has confirmed.

NuScale Power said in a statement yesterday that the study commissioned from the NNL supports the suitability of the company's NuScale Power Module - a 160 MWt, 50 MWe integral pressurized water reactor with natural circulation - for the effective disposition of plutonium.

NuScale module (NuScale) 122x460
NuScale's power module
(Image: NuScale)

The study, it said, evaluated scenarios with partial and full-core loading of MOX fuel and confirmed that MOX could be used in the NuScale core with "minimal effect on the reactor's design and operation". The study also demonstrated that a 12-module NuScale plant with 100% MOX cores could consume a 100-tonne stockpile of plutonium in about 40 years, "during which time it would generate approximately 200 million megawatt-hours of carbon free electricity".

NNL business leader for fuel and reactors Dan Mathers said, "The National Nuclear Laboratory has been pleased to work with NuScale on a commercial basis to help demonstrate the capability of their SMR in relation to MOX fuel." He added, "Reuse of the plutonium for low carbon power generation could be a valuable way forward for dealing with the UK's nuclear legacy."

NuScale CEO John Hopkins said, "This is an important step in the continued development of additional flexibility of the NuScale Power Module to operate on various fuel forms."

Last October, NuScale said it aims to deploy its SMR technology in the UK with the first of its 50 MWe units in operation by the mid-2020s. The company is looking for partners to make this happen.

US-based NuScale is developing its technology with a cost-sharing award from the US Department of Energy (DOE) worth $217 million over five years. The company wants to apply for design certification this year and it hopes to have its first unit in operation in late 2023, generating power in Idaho for prospective customer the Utah Association of Municipal Power Systems. NuScale, majority-owned by Fluor, plans a construction and operating licence (COL) application in late 2017 or early 2018. The company also expects to apply for a GDA in the UK in a similar timeframe.

More than 100 tonnes of plutonium are currently stockpiled at the UK's Sellafield site in Cumbria. However, the government is considering options for its re-use or disposal.

GE-Hitachi Nuclear Energy's Prism and Candu Energy's Enhanced Candu 6 (EC6) reactors are seen as "credible options" for managing the UK's plutonium stockpile, according to the UK's Nuclear Decommissioning Authority, but the government's preferred option for this remains reuse as MOX fuel. In early 2012, the NDA invited expressions of interest on potential alternative credible full lifecycle management options for managing the UK's plutonium stockpiles. The use of plutonium in MOX fuel had earlier been selected as the preferred route by the government. Four responses were received and the NDA shortlisted two of them - Prism and EC6 - for further consideration.

NuScale said another option under consideration is Areva's Convert proposal, which would reprocess the UK's stockpile of plutonium into MOX fuel. Areva has already been working with NuScale, having signed a contract last month to manufacture conventional fuel assemblies for the NuScale Power Module and provide a variety of engineering and testing services associated with the NuScale design.

Areva said it welcomed the results of the NNL study. In a statement today, it said: "This is further evidence that Areva's Convert proposal, which would reprocess the UK's stockpile of plutonium into MOX fuel, is an advantageous solution to address the UK plutonium stockpile." It noted that its reprocessing technology "is already commercially available, having been successfully industrially implemented and operational for more than 40 years with MOX fuel already used by 43 reactors worldwide".

Researched and written
by World Nuclear News