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Generation IV Designs Improve the Economics of Nuclear Power
By Simon Irish
Amid rising concerns about how we can decarbonize our whole energy system to address climate challenges, we are seeing greater awareness of nuclear energy’s important role. Top energy officials from Canada, United Kingdom, United States, and other countries have affirmed that nuclear energy is an essential part of a low-carbon future.
As advanced economies move towards nuclear again, it is important that we do not dismiss the clearly stated energy supply preferences of emerging economies in Asia and Africa trying to leap-frog over coal. They too recognize the environment and economic vitality that comes from nuclear power, and they clearly say they want civilian nuclear energy programs. Why would anyone want to dissuade them from pursuing a reliable source of clean energy?
Last year, the United States lifted its legacy prohibition on funding nuclear energy projects overseas when the U.S. International Development Finance Corporation (DFC) changed its Environmental and Social Policy and Procedures.
Developments such as these will help more of the non-OECD’s population of 6 billion people potentially see the benefits of nuclear power. Wood, charcoal, and coal are not the fuels of 21st century human progress. Let’s not forgot though that coal power built may western economies, and even Germany plans to continue using coal to generate electricity until 2038; for the moment it remains Europe’s largest coal consumer by far.
While its role in generating reliable, emission-free power is critical, nuclear energy’s market potential is limited by the economic consequences of nuclear technology choices made many decades ago.
That’s why Terrestrial Energy has made the technology and design choices necessary for strong nuclear power plant economics. These choices give Terrestrial’s Integral Molten Salt Reactor (IMSR®) power plant transformative economics, providing a form of a nuclear power that is strongly cost competitive with other sources.
The IMSR® uses a Generation IV molten salt technology, and its key feature is high temperature and low-pressure operation. This is only possible as molten salt coolants have high thermally stability, which has profound advantages. They are superior to the water used as the coolant in today’s nuclear power plants. Using water locks nuclear plants into low-temperature and high-pressure operation.
A nuclear power plant is just a machine; thermal efficiency is critical to the economic efficiency of any machine. Coal- or gas-fired power plants operate with thermal efficiency in the high 40 percent range. To compete with fossil-fueled power generation, nuclear plants at the very least must operate at a similar thermal efficiency. Unfortunately, nuclear plants using conventional (Generation III) nuclear technology, which is almost all of them, are stuck at only 30 percent thermal efficiency and with that only 30 percent capital efficiency.
However, operating at 700 degrees C, the IMSR® achieves 44 percent thermal efficiency. That is a 50 percent improvement! An IMSR® power plant will produce nearly 50 percent more kWh of electricity from the same-sized reactor. The commercial advantage is clear.
While thermal efficiency is the essential starting point for improving economics for nuclear power generation, other factors are important too, such as operating pressure. Conventional reactors operate at more than 100 times IMSR®’s pressure, creating a much higher engineering and safety burden, and that has cost implications.
Operating at low pressure, the IMSR® avoids these. In addition, using a molten salt fuel and coolant allows the IMSR® to incorporate to the greatest extent possible the virtues of inherent and passive safety for reactor operation. This has powerful cost benefits, and social license benefits as well.
Finally, the IMSR® design is commercially pragmatic and market-focused, and its fuel choice exemplifies this philosophy. The IMSR® uses standard assay low-enriched uranium (LEU), the same nuclear fuel as conventional reactors. This is the only reactor fuel commercially available today and so IMSR® deployment does not have to wait for a specialized fuel supply to develop. GE and Rolls Royce design aircraft engines that can run on Kerosene for good reason.
With these technology and design choices, we expect an IMSR® power plant to have construction costs of under U.S. $1 billion and to generate carbon-free electricity at less than U.S. $50 per megawatt-hour. These are the economics of true clean-energy alternative to fossil fuel combustion. They make an IMSR® power plant a bankable infrastructure project, which opens access to the capital essential for nuclear energy’s worldwide growth.
With high operating temperature, the IMSR® has applications beyond power generation. Its thermal energy can directly support many industrial activities, such as desalinating seawater, natural resource extraction, and hydrogen and synthetic transport fuel production. With these characteristics, IMSR® is an energy technology that can play a major role in decarbonizing the world’s primary energy supply where both heat and electric power are required.
The economics and industrial flexibility of IMSR® Generation IV nuclear power plant technology – together with its benefits of reliable, dispatchable, and carbon-free energy – give it remarkable market potential.
Learn more about our IMSR® power plant here: https://www.terrestrialenergy.com/technology/
Simon Irish is Chief Executive Officer of Terrestrial Energy.