More SMR vendor design reviews for CNSC

20 February 2018

The Canadian Nuclear Safety Commission (CNSC) is to conduct pre-licensing vendor design reviews (VDRs) of small modular reactor designs from NuScale Power and Westinghouse Electric Company. The reviews of the NuScale SMR and Westinghouse's eVinci micro reactor will incorporate the first two phases of the VDR process.

Westinghouse's vision of its eVinci micro reactor (Image: Westinghouse)

The CNSC offers the pre-licensing VDR as an optional service to provide an assessment of a nuclear power plant design based on a vendor's reactor technology. It is not a required part of the licensing process for a new nuclear power plant, but aims to verify the acceptability of a design with respect to Canadian nuclear regulatory requirements and expectations.

The three phases of the VDR process involve a pre-licensing assessment of compliance with regulatory requirements; an assessment of any potential fundamental barriers to licensing; and a follow-up phase allowing the vendor to respond to findings from the second phase.

The regulator said yesterday it had received applications for VDRs from NuScale Power and Westinghouse. It expects to begin the VDR for the NuScale design in mid-2018, but has not yet determined when it expects to start the review for the eVinci design. Given that both designs have progressed beyond the basic engineering phase, the CNSC said the first two stages of the VDR can be combined.

The CNSC is now involved with ten pre-licensing VDRs, all for small reactors with capacities in the range of 3-300 MWe.


NuScale's self-contained 50 MWe integral pressurised water reactor design houses the reactor core, pressuriser and steam generator inside a single containment vessel. A power plant could include up to 12 power modules, each 25 metres in length, 4.6m in diameter and weighing around 450 tonnes. Each module incorporates simple, redundant, diverse, and independent safety features.

The company in December 2016 applied for US regulatory design certification. The first commercial 12-module power plant, which will be owned by Utah Associated Municipal Power Systems and run by an experienced nuclear operator, Energy Northwest, is planned for construction on land owned by the US Department of Energy at the Idaho National Laboratory. It intends to apply for generic design assessment in the UK.


Westinghouse is developing the eVinci micro reactor as a small nuclear energy generator for decentralised generation markets, such as remote communities, or arctic mines. The company says the reactor design is a combination of nuclear fission, space reactor technologies and over 50 years of commercial nuclear systems design, engineering and innovation.

The reactor has a solid core, built around a solid steel monolith with channels for fuel pellets and heat pipes that remove heat from the core, and has minimal moving parts. Fuel is encapsulated in the core, which the company says significantly reduces proliferation risk and enhances overall safety for the user. The heat pipes enable passive core heat extraction and inherent power regulation, allowing autonomous operation and inherent load following capabilities.

The reactor is designed to run for more than ten years without refuelling. It can provide combined heat and power from 200 kWe to 25 MWe, and process heat up to 600 degrees Celsius.

Westinghouse said in October last year it aims to develop and demonstrate the eVinci reactor in less than six years, a timescale it says is possible primarily due to the small size and high technology readiness level of the individual components. The company plans to develop a full-scale electrical demonstration unit to reduce technology gaps and demonstrate manufacturability by 2019, and aims to qualify the eVinci micro reactor for commercial deployment by 2024.

Researched and written
by World Nuclear News