TerraPower, CNNC team up on travelling wave reactor

Friday, 25 September 2015

US-based TerraPower has signed a memorandum of understanding with China National Nuclear Corporation (CNNC) to develop its travelling wave reactor (TWR).

The MOU was signed in Seattle on 22 September by TerraPower CEO Lee McIntire and CNNC president Qian Zhimin.

After the signing, McIntire said, "The TerraPower-CNNC collaboration on advanced nuclear technology aims to benefit the world by pioneering new options in civilian nuclear energy that address safety, environmental and cost concerns." He added, "Additional work must be done to define what a possible joint venture may look like, but this MOU signals that we are well on track."

Initially developed in the 1950s, the TWR design resurfaced in the early 1990s, and was later patented by Intellectual Ventures, the company from which TerraPower was spun out of. The TWR is a liquid sodium-cooled fast reactor that uses depleted or natural uranium as fuel.

The core design of the original TWR concept envisages a moving region, or 'wave', in which the uranium is bred progressively into plutonium, which is the actual fuel that undergoes fission. However, in mid-2011 TerraPower announced a change of design to a standing wave reactor in order to address the problem of cooling a moving region. The current design would start the fission reaction at the centre of the reactor core, where the breeding stays, while fresh fuel from the outer edge of the core is progressively moved to the central region, as used fuel is moved out of the centre to the periphery.

TerraPower - a company largely funded by Microsoft founder Bill Gates - plans to build a 600 MWe demonstration plant, known as the TWR-P, by 2018-2022, followed by larger commercial plants of 1150 MWe from the late 2020s.

In February 2014, Babcock & Wilcox (B&W) signed an agreement to support the development of TerraPower's TWR. Under the agreement, B&W will provide TerraPower with services and program support, such as: design and fabrication of components; fuel fabrication process development, prototype fabrication and fuel services; reactor design engineering; reactor operations support; engineering services; flow loop testing; licensing support; and materials testing.

Researched and written
by World Nuclear News