Terrestrial Energy USA and Energy Northwest on 31 March signed a memorandum of understanding on possible siting, construction and operation of an Integral Molten Salt Reactor (IMSR) at the Idaho National Laboratory (INL) in southeastern Idaho. Terrestrial Energy USA, part of Terrestrial Energy Inc, is developing the IMSR for deployment in the US market. Terrestrial's IMSR integrates the primary reactor components, including the graphite moderator, into a sealed and replaceable reactor core. The reactor, which can produce 400MWt (190MWe), is a modular design for factory fabrication. Terrestrial hopes the IMSR can be brought to market in the 2020s and began a feasibility study in 2017 to site a commercial IMSR at Canadian Nuclear Laboratories' Chalk River site. The reactor design has already completed the first phase of the Canadian Nuclear Regulatory Commission's vendor design review. It announced in January that it plans to submit an application for design certification or for a construction permit to the US Nuclear Regulatory Commission by October 2019.

Energy Northwest is a not-for-profit joint operating agency comprising 27 public power member utilities from across Washington state. The agency develops, owns and operates a diverse mix of electricity generating resources, including the Columbia nuclear power plant, and says it continually explores new generation projects to meet its members' needs. In 2013, Energy Northwest signed teaming agreements with NuScale Power and Utah Associated Municipal Power Systems, as part of the Western Initiative for Nuclear collaboration studying the demonstration and deployment of NuScale small modular reactor power plants. A preferred site for the first NuScale SMR, also at INL, was identified in 2016 with an initial plant projected to be operational by 2024.

Earlier in March, the European Union supported Eurostars programme awarded funding to Denmark-based Seaborg Technologies for its Sealion project to speed up the commercialisation of molten salt reactors (MSRs) by developing powerful modelling software. The aim of the project is to develop multiphysics software to model complex dynamic behaviour of advanced nuclear reactors, particularly MSRs. The software will use highly accurate and reliable calculations to provide high performance computing techniques and regulatory compliance to pave the way for MSRs to be licensed under current regulatory systems.

Seaborg Technologies is developing a thorium-based MSR, the Seaborg Cube-100 (Compact Used Fuel BurnEr) and received a grant from Innovation Fund Denmark in 2017. Eurostars is a joint programme co-funded from the national budgets of 36 countries and by the European Union through the Horizon 2020 research and innovation programme, which has some €80bn of funding available for 2014-2020.