Nuclear energy is one of the most exciting and important parts of the future of clean energy and power. The next generation of nuclear reactors, called advanced nuclear reactors, are at the forefront of this quickly growing field. To discover more about advanced nuclear reactors and the role they play in the future, we talked to Chris Levesque, the president and chief executive officer of TerraPower. Levesque leads this nuclear innovation company in the pursuit of next-generation nuclear energy solutions and also oversees TerraPower’s new venture into therapeutic medical isotopes. 

His proven track record in scoping, planning, and implementing complex projects began with his service in the U.S. Nuclear Navy and features more than 30 years of experience in the nuclear field. He began his career as a nuclear submarine officer, supervising initial criticality and reactor startup testing, and led major new reactor build efforts at both Westinghouse and AREVA, overseeing projects in both the U.S. and Finland. He also serves on the Board of the Nuclear Energy Institute.

Chris Leveque a conversation with TerraPower about Advanced Nuclear reactorsu

Tomorrow’s World Today (TWT): Can you explain advanced nuclear energy and advanced nuclear reactors, as opposed to nuclear energy and nuclear reactors? (what does it mean that they are “advanced”)

Chris Levesque (CL): In the United States, existing commercial nuclear energy is generated by light-water reactors that utilize water as both a coolant and neutron moderator. Advanced nuclear reactors refer to the next generation, or generation IV nuclear reactor technology. There’s a variety of advanced reactors in development across the world. TerraPower and partners are advancing efforts to demonstrate the Natrium™ technology, which utilizes a sodium fast reactor and integrated energy storage system to offer a firm and flexible baseload source of electricity that is able to load follow. 

Additionally, TerraPower’s molten chloride fast reactor (MCFR) technology, which is a type of molten salt reactor, has the potential to operate at higher temperatures than conventional reactors, thus generating electricity more efficiently and without emissions. Its unique design also offers the potential for process heat applications and thermal storage. In December 2020, DOE selected the Molten Chloride Reactor Experiment (MCRE) proposal, with Southern Company as the prime, as a winner of the second Advanced Reactor Demonstration Program risk-reduction pathway. The MCRE project represents a significant inflection point in the technology demonstration roadmap for TerraPower’s MCFR, as the project will inform the design, licensing, and operation of an MCFR demonstration reactor.

Generation IV non-light water reactors offer many advantages including potential better economics, improved fuel utilization, higher operating temperatures for industrial process heat applications and integrated energy storage systems, and the ability to close the fuel cycle. Sodium-cooled fast reactors have the highest technology readiness levels of any advanced non-light water reactor. This enables the technology to be commercialized rapidly to have a meaningful impact on decarbonization.

The Natrium plant viewed from above.
The Natrium plant viewed from above
Photo Credit: TerraPower

TWT: What does the future of nuclear energy look like?

CL: Advanced nuclear reactors will play a very important role in the clean energy future. As energy demand continues to grow and leaders at all levels of government continue to set ambitious emissions-reduction goals, it is abundantly clear that the world needs more reliable, carbon-free energy. Advanced reactors, like the Natrium technology, are uniquely positioned to meet this need by providing carbon-free energy at a competitive cost with the ability to integrate seamlessly into electric grids with high levels of renewables.

TWT: How do advanced nuclear reactors help curb energy poverty? Your website states that “clean energy is the pathway to lift billions out of poverty.” Can you discuss this further?

CL: Energy poverty affects more than one billion people living without access to electricity. This means there is no power for major infrastructure, schools, hospitals, homes and businesses, communication, cooling and heating, food and medicine storage, and so much more. In addition to the negative impacts of energy poverty, approximately two-thirds of the world’s electricity comes from carbon-producing sources, which increase the effects of global warming and add pollution to the environment.

We believe that global problems like climate change and energy poverty can be solved by advances in nuclear energy. Advanced nuclear reactors can provide reliable, carbon-free energy to power electricity grids but also provide the power needed for industrial processes that currently rely on fossil fuels—such as desalinating water, providing district heating, or producing hydrogen, petrochemicals, or steel.

TWT: What are medical isotopes and how does nuclear energy work to advance them? How can this offer potentially lifesaving treatment for cancer?

CL: More than one in three people will be diagnosed with cancer in their lifetime. Fortunately, outcomes for cancer patients have improved tremendously, in part, due to advances in nuclear science and technology, and new approaches to the medical application of radioisotope technology.

The TerraPower Isotopes® (TPI™) program harnesses the company’s focus on nuclear science and innovation to apply it to the health care sector. The program is supporting medical research and innovation by developing advanced radioisotope generators that efficiently extract rare isotopes, like Actinium-225, with potentially life-saving qualities. Our experts developed these generators to increase efficiency and automation, enabling a robust supply of Actinium-225 intended for drug trials and the development of advanced therapies for cancer treatment.

Actinium-225 is an alpha-emitting radionuclide with the potential to effectively treat diseases such as prostate, breast, colon, and neuroendocrine cancers, melanoma and lymphoma. It can be attached to a molecule that will selectively target cancerous tissue and deliver the Actinium-225 to the cancer site, where the Actinium-225 alpha-emission can destroy the cancerous tissue with minimum damage to nearby healthy cells.

TWT: How does TerraPower work with partners? What are the benefits of this public/private partnership in nuclear power?

CL: TerraPower’s work has greatly benefited from collaborative partnerships with government, private-sector companies, universities, international organizations, and national labs like Idaho National Laboratory. In October 2020, TerraPower was selected to demonstrate the Natrium technology as part of the U.S. Department of Energy’s Advanced Reactor Demonstration Program with its technology co-developer GE Hitachi Nuclear Energy and engineering and construction partner Bechtel. This public-private partnership is a transformational event in nuclear energy.

In the advanced nuclear sector, the successful development and commercialization of a reactor relies heavily on government policy and regulation. As a result, government involvement helps to stimulate innovation and supports continued private investment. 

The demonstration project is intended to prove out the new technology’s design, licensing, construction, and operational features. The award brings public and private interests together and provides initial funding to build reactors that can be operational within the next seven years. 

Advanced reactor demonstrations build on a long history of public- and private-sector cooperation in the United States. Such efforts resulted in the development of railroads, the internet, the space program, and even the light water reactor technology used in today’s nuclear energy plants.

Read more about nuclear energy HERE, or stream Tomorrow’s World Today’s four-part exploration of nuclear energy on Science Channel GO and Discovery GO!

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