CNA Member Spotlight: Terrestrial Energy

Terrestrial Energy is developing a reactor that relies on liquid salt to cut costs and create new opportunities for nuclear power. The CNA recently sat down with Chief Executive Simon Irish to talk about Terrestrial Energy’s future.

WHAT MAKES LIQUID SALT DIFFERENT THAN A TYPICAL REACTOR?

There are two types of reactors: solid-fuel reactors, which use a liquid coolant, and liquid-fuel reactors in which both the fuel and coolant are one liquid. Our Integral Molten Salt Reactor (IMSR) is liquid-fuelled and is the basis for a much simpler and smaller power plant that can provide clean, carbon-free heat and power without needing a large amount of water for cooling. That means that the reactor can be placed in so many more locations and used in many new industrial applications. It can radically change the commercial position of nuclear energy and those companies involved in its development.

TELL ME A LITTLE MORE ABOUT USING SALT TO CREATE HEAT.

The biggest challenge for any reactor system is to remove the intense heat caused by nuclear fission. Conventional reactors use water to carry the heat away. Salts do that better. They melt at 500C, boil at 1400C, and can dissolve the uranium fuel. That means the fission heat is created right in the coolant. The heat and the coolant are inseparable, which improves safety. Also, the IMSR operates at 700C, which is far hotter than the 300C used in conventional reactors, and therefore makes our heat much more valuable to industry. You can do so much more with it and more efficiently.

HOW DOES IT WORK?

When uranium dissolves in liquid salt, it can be pumped around the reactor core as a fluid. Fission splits the uranium in the liquid salt and creates heat in the moderated area of the core. Heat exchangers transfer the heat from the liquid salt, via secondary salt circuits, into water, which boils and generates the steam that turns a turbine for power production. It is a remarkably simple and elegant system.

WHY MOLTEN SALT REACTORS?

Nuclear power could and probably has to, provide the large majority of industrial global energy for this century. It is highly scalable and has wonderful environmental characteristics. Molten salt reactor systems are a new and better way to meet modern needs for cost-competitive, clean, safe and, secure energy. Now is the time to commercialize this technology, which is what Terrestrial Energy is doing.

BENEFITS OF AN IMSR?

The IMSR holds great promise to deliver power cheaper than coal and natural gas. It is much more compact than other nuclear reactors, needs less land, burns one-sixth as much uranium fuel, and produces only one-sixth as much plutonium waste. It fits today’s energy markets needs very well indeed.

WHAT’S NEXT FOR TERRESTRIAL?

We are working to build an IMSR power plant and have it running by 2025. We want to start the regulatory approval process next year, and to share our vision and excitement with our fellow engineers and future business partners. We believe that that success is a short step away.