Advanced Nuclear Reactors

An "advanced nuclear reactor" is defined in legislation enacted in 2018 as "a nuclear fission reactor with significant improvements over the most recent generation of nuclear fission reactors" or a reactor using nuclear fusion (P.L. 115-248). Such reactors include LWR designs that are far smaller than existing reactors, as well as concepts that would use different moderators, coolants, and types of fuel. Many of these advanced designs are considered to be small modular reactors (SMRs), which the Department of Energy (DOE) defines as reactors with electric generating capacity of 300 megawatts and below, in contrast to an average of about 1,000 megawatts for existing commercial reactors. Advanced reactors are often referred to as "Generation IV" nuclear technologies, with existing commercial reactors constituting "Generation III" or, for the most recently constructed reactors, "Generation III+." Major categories of advanced reactors include advanced water-cooled reactors, which would make safety, efficiency, and other improvements over existing commercial reactors; gas-cooled reactors, which could use graphite as a neutron moderator or have no moderator; liquid-metal-cooled reactors, which would be cooled by liquid sodium or other metals and have no moderator; molten salt reactors, which would use liquid fuel; and fusion reactors, which would release energy through the combination of light atomic nuclei rather than the splitting (fission) of heavy nuclei such as uranium. Most of these concepts have been studied since the dawn of the nuclear age, but relatively few, such as sodium-cooled reactors, have advanced to commercial scale demonstration, and such demonstrations in the United States took place decades ago. The 115th Congress enacted two bills to promote the development of advanced nuclear reactors. The first, the Nuclear Energy Innovation Capabilities Act of 2017 (NEICA), was signed into law in September 2018 (P.L. 115-248). It requires DOE to develop a versatile fast neutron test reactor that could help develop fuels and materials for advanced reactors and authorizes DOE national laboratories and other sites to host reactor testing and demonstration projects "to be proposed and funded, in whole or in part, by the private sector." The second, the Nuclear Energy Innovation and Modernization Act (NEIMA, P.L. 115-439), signed in January 2019, would require the Nuclear Regulatory Commission to develop an optional regulatory framework suitable for advanced nuclear technologies. The 115th Congress also appropriated $65 million for R&D to support development of the versatile test reactor in the Energy and Water Development Appropriations Act, FY2019, along with funding for ongoing advanced nuclear research and development programs (Division A of P.L. 115-244). Continued debate over advanced reactor issues is anticipated in the 116th Congress. A fundamental question may be the role of the federal government in advanced nuclear power development. DOE's budget request for FY2020 focuses the federal role on "early stage research" rather than the more expensive stages of demonstration and commercialization. Controversy is also likely to continue over the need for advanced nuclear power. Supporters contend that such technology will be crucial in reducing emissions of greenhouse gases and bringing carbon-free power to the majority of the world that currently has little access to electricity. However, some observers and interest groups have cast doubt on the potential safety, affordability, and sustainability of advanced reactors. Because many of these technologies are in the conceptual or design phases, the potential advantages of these systems have not yet been established on a commercial scale. Concern has also been raised about the weapons-proliferation risks posed by the potential use of plutonium-based fuel by some advanced reactor technologies.

Nuclear engineers advancing the energy transition are understanding more about the next generation of nuclear plants; however, it is still difficult to access all the critical types, concepts, and applications in one location. Advanced Reactor Concepts (ARC): A New Nuclear Power Plant Perspective Producing Energy gives engineers and nuclear engineering researchers the comprehensive tools to get up to date on the latest technology supporting generation IV nuclear plant systems. After providing a brief history of this area, alternative technology is discussed such as electromagnetic pumps, heat pipes as control devices, Nuclear Air-Brayton Combined Cycles integration, and instrumentation helping nuclear plants to provide dispatchable electricity to the grid and heat to industry. Packed with examples of all the types, benefits, and challenges involved, Advanced Reactor Concepts (ARC) delivers the go-to reference that engineers need to advance safe nuclear energy as a low-carbon option. Describes theory and concepts on generation IV technology such as advanced reactor concepts (ARC) and electromagnetic pumps, and compares different types and sizes. Sets out the energy transition with critical carbon-free technology that can supplement intermittent power sources such as wind and solar. Explains alternative heat storage technology, including Nuclear Air-Brayton Combined Cycles. Introduces advanced main instrumentation systems for in-core probes.

This book discusses advanced Small Modular Reactors (SMRs) as a way to provide safe, clean, and affordable nuclear power options. The advanced SMRs currently under development in the U.S. represent a variety of sizes, technology options and deployment scenarios. These advanced reactors, envisioned to vary in size from a couple megawatts up to hundreds of megawatts can be used for power generation, process heat, desalination, or other industrial uses. In-depth chapters describe how advanced SMRs offer multiple advantages, such as relatively small size, reduced capital investment, location flexibility, and provisions for incremental power additions. SMRs also offer distinct safeguards, security and nonproliferation advantages. The authors present a thorough examination of the technology and defend methods by which the new generation of nuclear power plants known as GEN-IV can safely be used as an efficient source of renewable energy. Provides a unique and innovative approach to the implementation of Small Modular Reactor as part of GEN-IV technology; Discusses how Small Modular Reactors (SMRs) can deliver a viable alternative to Nuclear Power Plants (NPPs); Presents an argument defending the need for nuclear power plant as a source of energy, its efficiency and cost effectiveness, as well as safety related issues.

The terms for describing advanced nuclear power plants (NPPs) need to conform to the broad, general, common understanding by the public as well as by the technical community. This publication is a revision of IAEA-TECDOC-936 incorporating developments and initiatives since 1997 in the areas of advanced, evolutionary, and innovative nuclear reactor designs, description of design development phases, inclusive of relevant safety and regulatory terminology, consistent with current IAEA safety standards and glossaries. The objective of this publication is to provide Member States with up-to-date terms for describing advanced NPPs, to draw distinctions between design phases reflecting the maturities of designs, and to clarify definitions of commonly used terms in describing advanced NPPs.

Nuclear Power Reactor Designs: From History to Advances analyzes nuclear designs throughout history and explains how each of those has helped to shape and inform the nuclear reactor designs of today and the future. Focused on the structure, systems and relevant components of each reactor design, this book provides the readers with answers to key questions to help them understand the benefits of each design. Each reactor design is introduced, their origin defined, and the relevant research presented before an analysis of its successes, what was learned, and how research and technology advanced as a result are presented. Students, researchers and early career engineers will gain a solid understanding of how nuclear designs have evolved, and how they will continue to develop in the future. Presents reactor designs through history to present day, focusing on key structures, systems and components Provides readers with quick answers about various design principles and rationales Includes new approaches such as the micro-reactor and small-modular reactors

This book focuses on core design and methods for design and analysis. It is based on advances made in nuclear power utilization and computational methods over the past 40 years, covering core design of boiling water reactors and pressurized water reactors, as well as fast reactors and high-temperature gas-cooled reactors. The objectives of this book are to help graduate and advanced undergraduate students to understand core design and analysis, and to serve as a background reference for engineers actively working in light water reactors. Methodologies for core design and analysis, together with physical descriptions, are emphasized. The book also covers coupled thermal hydraulic core calculations, plant dynamics, and safety analysis, allowing readers to understand core design in relation to plant control and safety.