Handbook of Small Modular Nuclear Reactors

Daniel T. Ingersoll, Mario D. Carelli

• Publisher: Woodhead Publishing
• Year: 2014
• eBook ISBN: 9780857098535
• Topic: Technology & Engineering
• Subtopic: Mechanical Engineering
• Index: Technology & Engineering

Small modular reactors (SMRs) are an advanced, safe type of nuclear reactor technology that are suitable for small and medium sized applications including both power and heat generation. In particular, their use as individual units or in combination to scale-up capacity offer benefits in terms of siting, installation, operation, lifecycle and economics in comparison to the development of larger nuclear plant for centralised electricity power grids. Interest has increased in the research and development of SMRs for both developing countries as well as such additional cogeneration options as industrial/chemical process heat, desalination and district heating, and hydrogen production. This book reviews key issues in their development as well as international R&D in the field. - Gives an overview of small modular reactor technology - Reviews the design characteristics of integral pressurized water reactors and focuses on reactor core and fuel technologies, key reactor system components, instrumentation and control, human-system interfaces and safety - Considers the economics, financing, licensing, construction methods and hybrid energy systems of small modular reactors - Describes SMR development activities worldwide, and concludes with a discussion of how SMR deployment can contribute to the growth of developing countries

Part One

Fundamentals of small modular nuclear reactors (SMRs)

1

Small modular reactors (SMRs) for producing nuclear energy: an introduction

N. Todreas Massachusetts Institute of Technology, Cambridge, MA, USA

1.1 Introduction

Just what are small modular reactors (SMRs)? This question is first answered simply along with a brief history of the evolution of this class of reactors. Subsequent sections detail the incentives and challenges to achieving successful commercial deployments, the different types of SMRs based on coolants employed, and, finally, the current status and future trends in the worldwide effort to develop and deploy this reactor type.

1.1.1 Defining SMRs

‘Small’ refers to the reactor power rating. While no definitive range exists, a power rating from approximately 10 to 300 MWe has generally been adopted. The minimum rating assures that the reactor delivers power suitable for the practical industrial application of interest. The maximum rating constrains these designs to power levels at which the expected advantages of serial production and incremental deployment as well as the match to electric grid siting opportunities and constraints can be realized.

‘Modular’ refers to the unit assembly of the nuclear steam supply system (NSSS) which, when coupled to a power conversion system or process heat supply system, delivers the desired energy product. The unit assembly can be assembled from one or several submodules. The desired power plant can then be created from one or several modules as necessary to deliver the desired power rating. Importantly the deployment of modules can also be sequenced over time both to match regional load growth and to levelize the timing of capital spending over a prescribed time horizon. Construction of the plant by assembly of factory-built elements or modules is the technique of modular construction. Although it is an integral part of the construction strategy envisioned for all SMRs, this technique is not uniquely applied to SMRs. Rather, it is now being employed for relevant construction elements of nuclear power plants of all power ratings, although the modules for large plants are considerably different in size, not typically amenable to rapid assembly as is being proposed for SMRs.

‘Reactor’ is a term more broadly applied to vessels in which all manner of chemical processes are conducted. However, in our case, reactor refers to a system in which a controlled nuclear fission process is conducted.

1.1.2 Strategy for development of SMRs

Small reactors and the modular construction of reactors are not new. Historically, early reactors for commercial production of electricity were of small size, a consequence of the prudent engineering process of constructing plants starting at small ratings to gain the needed construction and operating experience necessary to move confidently to larger ratings. Now, after a half-century of experience, commercial civil reactors are being deployed with ratings up to 1660 MWe. Additionally, small units were built for terrestrial deployment to provide electric power for remote, vulnerable military sites; for ocean deployment for propulsion of submarines, naval and commercial ships and for aircraft propulsion. Modular construction techniques historically have also been used for serial production of selected products. However, what is new is the vision of small rated power reactors composed of a single or multiple modules sized to markets of small- or large-sized electric grids, thereby creating new nuclear generating sites which require significantly reduced capital investments and capital investment rates. The further economic premise is that electric generation cost can be made sufficiently comparable to that of existing large-sized plants by employing a strategy of economy of numbers (manufacture of multiple identical modules) and simplification of design versus the traditional economy of scale.

1.1.3 Evolution of SMRs

Commercial electric power began with small reactors of light-water-cooled design. Key examples are the Shippingport, 60 MWe reactor designed by the Westinghouse-operated Bettis Naval Atomic Power Laboratory, which started operation in 1958; the Yankee Rowe reactor, 185 MWe (Westinghouse) in 1960; the Indian Point One reactor, 275 MWe (B&W) in 1962 (all pressurized water reactor [PWR] designs); and Dresden 210 MWe (General Electric) in 1960 (a boiling-water reactor (BWR) design).

The eight military reactors for terrestrial application developed by the US Army Nuclear Power Program included (1) the stationary plants operated at Fort Belvoir, Virginia, which started operation in April, 1957, seven months before Shippingport and five years before criticality of the Ft. Greely, Alaska reactor; (2) the portable reactor operated at McMurdo Sound at the South Pole in 1962; and (3) a barge-mounted reactor operated off the coast of Panama City, Panama, in 1967. These plants ranged from 1.75 to 10 MWe and performed either a heating or desalinization function in addition to the generation of electricity. Another example of a portable reactor is the Russian PAMIR reactor designed primarily to power remote military radar outposts. The first was the TES-3, a 2 MWe nuclear plant completed in 1961. The design was modified in the 1980s to a smaller, more mobile 630 kW reactor.

The much larger US naval program, which pioneered the application of nuclear power for the propulsion of submarines and surface ships, has produced multiple pressurized water reactors and one sodium-cooled reactor of small ratings. Additionally, several countries have followed suit with naval propulsion – most notably Russia, which expanded its development of water-cooled submarine reactors to submarines using lead-bismuth coolant and has also built nuclear powered naval surface ships and ice-breakers.

Commercial (merchant marine) propulsion has also been exploited through the development of ocean freighters and icebreakers. Four freighters, all with reactors of light-water design, have been built and operated albeit without commercial success: (1) the US Savannah, 74 MWt, in effective service starting 1962; (2) the German Otto Hahn, 38 MWt, 1968; (3) the Japanese Mutsu, 36 MWt, 1972; and (4) the only vessel still in operation under nuclear power, the Russian Sevmorput, 135 MWt, delivered in 1988, which also has ice-breaking...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright page
• List of contributors
• Woodhead Publishing Series in Energy
• Preface
• Part One: Fundamentals of small modular nuclear reactors (SMRs)
• Part Two: Small modular nuclear reactor (SMR) technologies
• Part Three: Implementation and applications
• Part Four: International R&D and deployment
• Index