Canada reviewing ten small nuclear reactor designs including eVinci solid state microreactor

The Canadian Nuclear Safety Commission (CNSC) will have pre-licensing vendor design reviews (VDRs) the NuScale 50 MWe SMR and Westinghouse’s eVinci microreactor. The CNSC is now involved with ten pre-licensing VDRs, all for small reactors with capacities in the range of 3-300 MWe.

The NuScale design review will start in mid-2018. It has not been 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.

eVinci

Westinghouse is developing the eVinci microreactor as a small nuclear energy generator for decentralized 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 refueling. 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 microreactor for commercial deployment by 2024.

The
key benefits of eVinci are attributed to its technology:
Solid Core:
* Encapsulates fuel to significantly reduce proliferation risk
* Enables inherently safe core due to strong negative temperature feedback

Heat Pipes:
* Eliminates the need for reactor coolant pump and all associated auxiliary systems to enable compact packaging and simple design

* Can inherently adjust heat load, thus allowing easier autonomous load following

* Can operate at higher temperatures to enable higher efficient power conversion system and high-grade process heat Both heat pipes and the solid core together make the eVinci micro reactor a “solid state reactor” with minimal moving parts, which is key to the reliability and maintenance-free design of a long-life decentralized energy generator.

NuScale

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.