The JSC AKME Engineering (AKME Engineering, 2013), a joint venture of the State Atomic Energy Corporation Rosatom and the private JSC EvroSibEnergo, has
developed the design of the SVBR-100 reactor. The SVBR-100 is a small modular reactor of 101.5 MW(e) per module cooled by lead-bismuth eutectics. It is based on the experience of the propulsion reactors of the Russian alpha-class submarines which successfully operated in 1970s-1980s and gained operational experience of 80 reactor-years. The Russian Federation is the only country in the world with positive experience of reactors cooled by lead-bismuth eutectics. However, this experience so far relates to non-civilian application reactors.

The Russian program for marine propulsion reactors has resolved the two major issues relevant for lead-bismuth eutectics coolant, namely those of corrosion/erosion — free operation of structural materials in the coolant flow at temperatures below ~500 °C and of 210Po trapping and removal, based on data from p. 126 of Current status, technical feasibility and economics of small nuclear reactors (NEA-OECD, 2011) and on data from IAEA (2007). Moreover, a reported accident with spillage of the primary coolant has demonstrated that extra-irradiation doses to personnel could be effectively avoided during spillages and during the subsequent repair works at a factory (IAEA, 2012b).

The design and operating characteristics of the SVBR-100 are summarized in Table 17.3. Table 17.4 gives the core and fuel design characteristics.

Unlike its marine propulsion prototypes in which beryllium moderators were used in the core, the SVBR-100 is a reactor with fast neutron spectrum. Generically, this means that a substantial amount of R&D would be required for qualification and licensing of the new reactor.

The SVBR-100 is being designed as a modular reactor for single-module or multi-module nuclear power plants with optional co-generation capacity. Being a fast reactor, it could be flexible in fuel cycle options, i. e., easily adjustable to operation with different types of fuel — uranium, uranium-plutonium, uranium-transuraniums and uranium-thorium-based oxides or nitrides — in a once-through or closed nuclear fuel cycle, effectively matching the fuel cycle options of the day (IAEA, 2007). When operated with advanced ‘dense’ types of fuel (e. g., nitrides) in a closed nuclear fuel cycle, SVBR-100 could ensure preservation of its fissile inventory through an infinite number of recycles. In this case the reprocessing becomes essentially reduced to just removal of fission products and addition of some fertile material, e. g., depleted uranium (Kuznetsov and Sekimoto, 1995).

The SVBR-100 could be used for base load electricity generation within single or multi-module plants of different capacity. A load following option is, in principle, possible and could be considered for future design modifications. Several conceptual studies of 4- and 16- module SVBR-100 based plants have been developed in the Russian Federation (IAEA, 2007). Some of these designs consider a partly underground location of the reactor modules which, together with other features of the SVBR-100, makes these reactors the closest match to the philosophy of SMRs being pursued in the USA.

Figure 17.5 presents the schematics of the equipment layout in the SVBR-100 primary circuit. Different from sodium-cooled fast reactors, the SVBR-100 plant has no intermediate heat transport system. This is because lead-bismuth eutectics do not react exothermically with water or air. The reactor is pool type with primary

circulation provided by the pumps with externally located drives (see Figure 17.5). There is a very small excess pressure in the primary circuit (inert gas with an excess pressure of 0.1 MPa fills in the space above the coolant-free level). The circulation scheme is optimized to prevent gas or steam bubbles from passing through the reactor core in accidents.

Two reactor vessels are provided, the main vessel and the guard vessel. The guard vessel is immersed in a tank of water at atmospheric pressure with bubbling devices to facilitate decay heat removal in normal shutdown and in accidents. The secondary circuit operates on saturated steam, so that steam separators are being included in the design.

The relatively high melting temperature of the lead-bismuth eutectics (125 °C)

requires heating the reactor internals and the coolant before initial supply of the latter to the reactor vessel. It also may require heating of the shutdown reactor if the spent fuel composition in the reactor does not ensure enough of decay heat to keep the primary coolant liquid. Systems to accomplish such operations have been developed and applied in the Russian marine propulsion reactor program. Moreover, a procedure for safe freezing/unfreezing of the reactor coolant based on a particular time-temperature curve has been developed and tested on a land-based facility. No further details of these technologies are available. The overall layout of the reactor module appears very compact, as shown in Figure 17.6.

The inherent and passive safety features of the SVBR-100 include (IAEA, 2007, 2012a):

• low-pressure primary coolant system, contributing to the prevention of LOCA (Level 1 of the defense in depth);

• very high boiling temperature of Pb-Bi eutectics (1670 °C at atmospheric pressure), double reactor vessel, relatively high temperature of Pb-Bi eutectics freezing (125 °C at atmospheric pressure) and location of the reactor module in a water tank, practically excluding LOCA

and limiting potential radioactivity release in accidents with core melt (Level 1 and Level 4 of the defense in depth);

• chemical inertness of Pb-Bi in air and water, preventing fires and explosions (Level 1 of the defense in depth);

• a pool type design of the reactor with high heat capacity of the primary circuit, ensuring high thermal inertia in transients (Level 2 of the defense in depth);

• negative optimum reactivity feedbacks, including very small reactivity margin for fuel burn-up achieved with ‘dense’ types of fuel at the expense of high conversion or a very small breeding ratio (1.05) in the reactor core, preventing reactivity-induced accidents (Level 1 of the defense in depth);

• a high level of natural circulation of the primary coolant sufficient to remove the decay heat from the core (Level 3 of the defense in depth);

• a primary coolant flow path organized to prevent the possibility of steam or air bubbles from getting into the reactor core, to avoid prompt criticality events owing to positive void worth (Level 1 of the defense in depth).

In addition to the above-mentioned, the SVBR-100 incorporates shutdown systems based on mechanical control rods inserted by gravity and by the force of springs and two diverse passive decay heat removal systems. A steam generator leak localizing system is also included in the design to prevent the ingress of pressurized steam from the secondary into the primary circuit owing to a steam generator tube rupture

(Level 3 of the defense in depth). Reinforced concrete containment is provided to prevent hypothetical radioactive releases beyond the plant boundary.

The seismic design of the SVBR-100 incorporates features to ensure safe reactor shutdown at 0.5 g PGA. Specifically, the reactor is immersed in a water tank which acts as a seismic-resistant structure.

The predicted core damage frequency of 10-8/year (IAEA, 2012c) is primarily because Pb-Bi coolant is chemically inert with water and air, allows for primary circuit operation at near-atmospheric pressure and has a proven capability to self-cure cracks (freezing temperature 125 °C). Moreover, it has a very high boiling temperature (1670 °C), requires no intermediate heat transport system in plant design and ensures a high level of natural circulation in loss-of-flow accidents. Altogether, the above — mentioned features make it possible to develop a simple and robust small reactor design. Additionally, the integral layout of the primary circuit includes a free level of the coolant with inert gas volume above it. The primary flow path is organized in a way that gas or steam bubbles potentially coming from steam generator are released to the gas volume above the free level before the coolant is directed to the reactor core.

As of early 2013, the R&D phase for the SVBR-100 has been completed and design activities were in progress to prepare for the construction of prototype reactor. The focus of the R&D was to adapt the naval lead-bismuth coolant reactor technology to a commercial power reactor (IAEA, 2007). Current activities are focused on the design of fuel, reactor core and primary circuit components, with fuel element design being a priority. As a possible future evolution of the SVBR-100 technology the conceptual proposal of a smaller, perhaps, barge-mounted reactor of 10 MW(e), named SVBR-10, has been developed (IAEA, 2010).

If fossil technology is locked in for the developing world, with its growing energy needs (IEA, 2011), then even if high-income countries achieve more rapid decarbonization, the deleterious environmental effects will nevertheless be shared by all for longer. Conversely, once carbon is penalized, however, existing investment in CO2-emitting energy types may need to be trashed (Stern, 2012), thus wasting the scarce capital of developing countries.

In a global perspective, where energy demand goes unsatisfied in poorer or energy — hungry regions, or the water supply (often intertwined with energy) is imperilled (G-Science Academies, 2012), social unrest and political instability could result (Lee et al., 2012).

Energy planning decisions made now will threaten or support the economic future of developing countries; oil-price volatility, for example, will affect them in proportion to their reliance on diesel and heavy fuel oil (Yepez-Garcia and Dana, 2012). Conversely, even the shortest refuelling interval of proposed SMR designs (14 months, with an upper range of 10 to 30 years for sealed-unit designs), would protect them from fuel-price volatility (IAEA, 2012). Nevertheless, long-term fuel-supply contracts, with a limited number of suppliers globally, could present multifaceted challenges for developing countries (IAEA INPRO DF3, 2011).

Finally, timing is a crucial factor because of the overlap of climate, economic and social pressures (IEA, 2011). The less able, because of polluting energy choices, developing countries are to meet CO2-reduction targets, the more responsibility they will have to assume for increased climate change, and the greater burden will fall on them and on developed countries to curtail emissions in order to compensate.

Contributions of inherent and passive features of ACP100 at this defense in depth level are as follows: when core uncover is assumed, only for analytic purposes, low heat-up rates of fuel elements in the exposed part of the core are predicted, if the geometry is still intact. The characteristic time of core melting is long, eventually preventing temperature excursion due to a metal-water reaction, which in turn limits the hydrogen generation rate. The hydrogen concentration in the containment is reduced by catalytic recombiners. There is sufficient floor space for cooling of molten debris and extra layers of concrete are used to avoid direct exposure of the containment basement to debris.

18.3.7.4 Level 5: Mitigation of radiological consequences of significant release of radioactive materials

The following passive features of ACP100 make a contribution to this defense in depth level: relatively small fuel inventory, compared with larger NPPs; slower progression of accidents and increased retention of fission products (facilitated by such features as reduced power density, increased thermal inertia, etc.); the containment is located inside the airplane protection concrete and underground building, which reduces the release of fission products due to local deposition. The ACP100 concept provides for extended accident prevention and mitigation by relying on the principles of simplicity, reliability, redundancy and passivity.

Except for the small nuclear power stations constructed around 1970, there has been no deployment of SMRs in Japan. After the severe earthquake on March 11, 2011, followed by the severe accident at the Fukushima Dai-ichi nuclear power station, deployment of nuclear power plants has basically been frozen in Japan, including deployment of SMRs in Japan. Since the policy for nuclear energy utilization has been under discussion in Japan after the Fukushima Dai-ichi accident and has not yet been determined, it is difficult to present a perspective for the SMR deployment in Japan at this time (February 2014).

However, the activities for deployment of some Japanese SMR concepts in other countries are continuing. One of them is the 4S (described in Section 19.3.5) deployment activity in Alaska, USA, which is under preliminary review by the US Nuclear Regulatory Commission. The other is the HTR50S (mentioned in Section 19.3.4) deployment activity in Kazakhstan, to be realized in the 2020s.

19.2 Future trends

As mention in the previous section, the Japanese policy for the nuclear energy utilization has been under discussion since the Fukushima Dai-ichi accident. It is difficult to present the likely future trend in Japan. After the Fukushima Dai-ichi accident, safety requirements have become more severe. Some SMR design concepts may need to be changed or checked against the new requirements.

Since the deployment of nuclear power plants is not expected to be easy in Japan, the SMR deployment abroad would be one likely future trend in Japan. In such a situation, there are two possibilities for the SMR deployment. One is the use based on the experienced LWR-based reactor. The other would be the use of new and non-LWR-based reactor. It can be said that the Japanese SMR have the potential to answer both possibilities.

19.3 Sources of further information and advice

A valuable source of further information is the new revision of the IAEA-TECDOC on the SMR status in the world. The revision of the TECDOC has been issued around every five years. The websites of the Japanese vendors of Mitsubishi, Toshiba and Hitachi would be other information sources, using keywords of the SMR and each reactor, such as IMR, CCR, DMS and 4S. The JAEA website is also valuable for the gas-cooled concepts of GTHTR300 and HTR50S. Also, the papers submitted to the international conferences, such as ICONE, ICAPP and ANS topical meeting on the SMR, would be valuable.

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The JSC NIKIET named after N. A. Dollezhal (NIKIET, 2013) — an enterprise belonging to the State Atomic Energy Corporation Rosatom — develops conceptual designs of the two factory fueled SMRs intended for autonomous (unmanned) operation over a long refueling interval within a land-based and a seabed-based NPP. The first of this designs, named UNITHERM, is a somewhat unusual indirect cycle PWR of 2.5 MW(e) with an intermediate heat transport system. The reactor is intended for autonomous operation in the course of 25 years within a land-based plant. The second, newer, design named SHELF is an indirect cycle PWR intended for autonomous operation in the course of 4.6 years within an unmanned seabed-based NPP. The design and operating characteristics of the UNITHERM and SHELF are given in Table 17.5. Table 17.6 presents the core and fuel design characteristics for these reactors.

The UNITHERM plant is being developed to provide electricity and heat to small (e. g., mining) enterprises and settlements located in remote areas with severe climatic conditions. The SHELF seabed-based plant is being developed to act as an energy source for the offshore oil and gas mining enterprises.

Figure 17.7 shows a somewhat unusual three-circuit scheme of the UNITHERM reactor. The UNITHERM is a co-generation plant producing heat for district heating or steam for industrial applications. In such a reactor an intermediate heat transport circuit is needed to prevent radioactivity from getting into the distribution network for district heating or industrial applications.

The heat generated in the reactor core is first transferred through a heat exchanger to the independent intermediate heat transport circuit located in an isolated volume within the reactor pressure vessel. Both, the primary and the intermediate heat transport systems operate on natural circulation of the coolant. From the intermediate circuit heat is then transferred to a power circuit through a steam generator located in a module outside of the reactor pressure vessel.

The intermediate circuit of UNITHERM consists of several parallel sections/units each of which is a thermosyphon housed in an individual vessel with the individual steam generator section. If one of the steam generators’ surfaces in one of the sections is ruptured, the corresponding section is being cut off using the lock valves on the

consumer circuit. The plant need not be stopped (it could continue operation with other sections) and the repair of the lost section could be accomplished during the scheduled repair period.

Very low steam parameters are used in the power circuit (see Table 17.5) and, hence, the energy conversion efficiency is also very low (12.5%). When needed, the plant could also produce steam for industrial applications. For this purpose steam is being extracted from the turbine, and the heat extraction circuit is operated on forced circulation of the medium (steam) (IAEA, 2007).

Radiator Evaporator Steam generator

Pressurizer

Intermediate heat exchanger Core

Reactor pressure vessel

The UNITHERM reactor is being designed for autonomous operation. To ensure safety in such operation yet another circuit shown in the upper part of Figure 17.7 is added. This circuit — actually a purely passive safety system — consists of a continuously operated heat exchanger — evaporator and the radiator connected to evaporator, cooled by atmospheric air at ambient conditions (IAEA, 2007). This circuit is capable of bringing the reactor to a hot standby condition with no operation of the control rods and acts as a decay heat removal system in accidental conditions, e. g., in the event of a loss of the normal heat removal path to the network for district heating (IAEA, 2007).

UNITHERM is being designed for operation in the severe climatic conditions of the Russian north and east, where the ambient temperatures undergo seasonal changes from -55 to +35 °C. To make the reactor continuously operable under such conditions options are being examined to use ammonia, ethylene glycol or alcohol instead of water in the intermediate circuit (IAEA, 2007).

A general view of a seabed-based NPP with the SHELF small reactor is given in Figure 17.8. The reactor is a PWR of integral primary circuit design with in-vessel steam generators, pressurizer, control rod drives and sealed canned pumps (graphics not available) (IAEA, 2012c). The plant has two turbine generators, each connected to one of the two in-vessel steam generators. The reactor itself is immersed in the water pool located in the bottom part of the primary steel containment. This pool
contains metal structures which, together with water, act as a radiation shielding, but also take on the functions of a heat sink.

The NPP shell is designed to withstand a water depth of 300 m, although the targeted depth of a seabed site is 50-100 m. Autonomous operation is foreseen with reactor control being executed from the water or land based control centre (e. g., oil platform). The electricity is supplied to the on-water or under-water user (e. g., a gas mining facility) using another cable.

The SHELF plant is being designed for unmanned operation during the whole cycle of operation between refuelings. For the refueling, it is being raised to the surface and brought to a refueling base (e. g., a dedicated ship). However, as shown in Figure 17.8, the seabed-based plant has an on-board control panel which could be used in emergencies or during a start-up by members of divers’ missions.

Both UNITHERM and SHELF incorporate experience from the design of small marine propulsion reactors. Specifically, they use so-called self-spaced cylindrical fuel elements with the external twisted ribs and employ no spacer grids. The fuel is borrowed from the Russian experience with marine propulsion reactors; Zr coated dispersed UO2 particles in a Zr matrix coated by silumin (Si-Al). Such fuel, often referred to as ‘cold’ fuel (owing to its exceptional heat conductivity characteristics), is also capable of very high burn-ups (IAEA, 2009). However, in the cases of the UNITHERM and SHELF the attained burn-ups are well below those achieved in the state-of-the-art NPPs with large reactors. The reason for this is that, notwithstanding the long refueling intervals, the average core power density in these reactors is low (see Tables 17.5 and 17.6).

Being designed for autonomous operation, the UNITHERM and SHELF reactors

Reactor

Figure 17.8 General view of the SHELF seabed-based NPP, reproduced with permission by the IAEA from IAEA (2012c).

rely strongly on the inherent and passive safety features. The inherent features include low core power density and large thermal inertia of the primary circuit owing to the relatively large inventory of the primary water coolant (IAEA, 2007, 2012c). The reactors employ compact modular (UNITHERM) or integral primary circuit designs minimizing the list and scope of possible LOCA.

The state-of-the-art I&C systems are being employed. The reactors have no liquid boron reactivity control systems. All safety systems in both designs are passive, including the mechanical control rods driven by gravity and the redundant and diverse passive decay heat removal systems. Specifically, UNITHERM incorporates an independent passive decay heat removal system based on an evaporator cooled by external air, as shown in the upper part of Figure 17.7. SHELF has the bottom part of the reactor vessel immersed in a pool of water located in the bottom part of the primary steel containment. A reliable ultimate heat sink for the SHELF reactor is provided by abundant seawater at ambient temperature.

Both reactors provide for a high level of natural circulation of the coolant. In UNITHERM, the circulation in the primary and intermediate circuit is natural in the normal operation mode (IAEA, 2007). In SHELF, natural circulation is sufficient to remove the decay heat and could also remove heat from the reactor operated at 65% of the rated power (IAEA, 2012c).

Both designs incorporate measures to prevent the core becoming uncovered in accidents, such as compact primary containments and reactor vessel penetrations located well above the core. Double containment is provided in both designs, as well as passive systems of the primary containment cooling.

Both design concepts incorporate provisions for protection against possible impacts of external events. The UNITHERM reactor is being designed for the seismic loads corresponding to 8-9 on the MSK 64 scale (IAEA, 2012c). For SHELF, the issue of protection against external even impacts is more complex, specifically because of the absence of internationally acknowledged requirements on protection against external event impacts for seabed-based NPPs. Seismic impacts may roughly be the same; however, tsunamis are not effective at depths around 100 m. Aircraft impact may be mitigated using steel nets around the plant. Resistance to torpedo attacks needs to be clarified.

SHELF has the evaluated core damage frequency 10-6/year. There is no published data on core damage frequency for the UNITHERM; however, according to its designers, this value is similar to, or below, the corresponding value for the SHELF.

According to IAEA (2007), cited with permission by the IAEA,

‘the UNITHERM concept is based on the experience of NIKIET and other Russian institutions and enterprises in the development of marine nuclear installations. The experience is available in the form of design approaches and technologies covering many aspects of nuclear engineering, such as fuel elements, structural materials, metal treatment, welding, heat exchange equipment, water chemistry, etc. In view of this, the UNITHERM NPP may require no major technology development effort to be implemented.’

So far, conceptual design of the nuclear island has been developed. In 2013, activities to design complete NPP were in progress.

SHELF is at the conceptual proposal stage and some activities for it have been carried out in the 2010s. Those were mainly related to the overall nuclear island and plant concept. Although it claims to be based on the Russian experience in the development of marine nuclear propulsion reactors, its further development is likely to include substantial amounts of R&D related to the targeted seabed-based location of the plant. Early in 2013, the activities for SHELF were at a standstill, pending the progress in the financing from the Russian companies examining options of oil and gas mining from the bottom of the Barents Sea.

The trade-offs can be heavy. Developing countries would be penalized and their access to international development aid and even infrastructural finance could be imperilled because in the increasingly carbon-constrained environment, under new standards, the use of polluting fossil fuel and concomitant water usage would prevent them from meeting carbon-reduction targets and harm the environment.

Moreover, in the perspective of development itself, if a disproportionate amount of the national budget is allocated to purchase fossil fuels, these sums are effectively sequestered from other high development and national priorities such as potable water distribution, adequate schooling, health care, housing, judiciary, and so forth. A switch to small-scale nuclear power could therefore release these funds for social services and other government functions, strengthening the country, and help to free it from debt.

In the Jamaican example, the causal link between energy cost, industrial activity and national wealth is not opaque, but a matter of discussion for the daily papers: ‘[a proposed fossil] plant will lower the high cost of energy that currently threatens the viability of the bauxite/alumina sector, which earns the third-highest levels of foreign exchange for Jamaica,’ (Jackson, 2013).

The potential still remains for an SMR program itself and the attendant infrastructure to saddle countries, especially nuclear newcomer countries, with increased debt. Therefore appropriate financing and institutional mechanisms are needed to support timely SMR access in newcomer countries.

SMRs’ comparatively small project size could make them apt for innovative fleetwide project-finance mechanisms; alternatively, BOO (Build-Own-Operate by the vendor) or BOOT (Build-Own-Operate-Transfer to the user) mechanisms could buy countries time to build up the human-resources and operational contingent without in the meantime sacrificing the benefits of SMR power.

There is increasing political, social and market scrutiny of the environmental and economic sustainability of investments and infrastructure. On the one hand, sustainability is becoming a higher priority for energy and infrastructure planners, as well as commercial utilities, and funds that finance these ventures, in order to protect their infrastructure investments. On the other, since vulnerable populations in developing countries are disproportionately affected by climate change (Dell et al., 2012), sustainability is not abstract, but is a survival issue (Hinshaw, 2010; Chonghaile, 2012). SMRs would be able to fulfil sustainability criteria to the satisfaction both of the funders and of the overarching purpose the criteria represent.

18.4.1 HTR-200

With the HTR-10 operation and experiments serving as a supporting technological test bed, the HTR-200 commercial demonstration plant is being promoted. China Huaneng Corporation, China Nuclear Engineering Construction Corporation and Tsinghua University have established Huaneng Nuclear Power Development Co., Ltd. After siting evaluation, conceptual design, basic design, safety analyses and Fukushima accident safety inspection, the Chinese government officially approved the start date on December 9, 2012. The first demonstration HTR-200 plant is now at the construction stage. The first demonstration HTR-200 is located in Shidao Bay, Shandong province. The time limit is 50 months, including 18 months for construction, 18 months for installation and 14 months for pre-commission.

D. Goodman Consultant, USA

20.1 Introduction

The planet is experiencing a combination of increased economic output from the global South with acute and cumulative effects of climate change that affect poorer countries the most, a heightened general awareness of the disparities of quality of life, and a deficit of social trust (UNDP, 2013). The current global predicament demands a revaluation.

Developing countries present distilled instances of systemic problems and solutions. Similarly, small modular reactors (SMRs) distil the operational experience and lessons learned, from submarines and large reactors and hazards; and incorporate cooperation with natural processes, such as gravity, evaporation and condensation, in their concepts and designs. SMRs are to nuclear as ‘developing countries’ are to the world: a concentrated instance of the whole; and they belong together.

Generic development issues are intensified in the case of nuclear. SMR deployment brings into focus poignant, generic issues of development, such as debt, national priority, natural resource endowments and industrial planning, climate change, technological competence, the need for durable institutions, educational and human resources, and in some cases limited capital. Nevertheless, SMRs’ intrinsic technical features, such as their size, modularity, simplified operation and inherent safety features, make them particularly well suited to the circumstances of developing countries.

As discussed in Chapter 3 of this Handbook, SMRs are a robust, ‘forgiving’ nuclear power technology, designed for simplicity and plant resilience, and to incorporate inherently or ‘passively’ safe features such as natural circulation for core cooling, incorporating most primary components in a single vessel, long coping periods to handle interrupted backup power supply, and generally designed for below-grade or barge deployment with the intended result of much reduced risk of accident, and fewer and less acute consequences in case of accident (Carelli, 2014; Ingersoll, 2011).

A promising feature for the economics of wide SMR deployment in developing countries is the modularity of some designs, which refers to the incorporation of all major safety-significant systems within one module, to the potential of modules to be standardized and factory-built in series, with minimum site-specific design

Handbook of Small Modular Nuclear Reactors. http://dx. doi. Org/10.1533/9780857098535.4.485

Copyright © 2015 D. Goodman. Published by Elsevier Ltd. All rights reserved.

and construction. It also refers to the possibility of scaling-up power production in increments, building and putting additional modules into service over time, which would reduce the initial capital outlay and overall investment risk (Barkatullah, 2011; Kessides and Kuznetsov, 2012). There is also potential for SMR components to be manufactured indigenously, with a corresponding positive impact on industry.

In themselves and by analogy, SMRs can become the catalyst for development and capability: ‘There is no country in the world that has made significant development without embracing nuclear technology. Not just because nuclear generates electricity in an affordable way, but if you are able to demystify the mysteries and the myths surrounding nuclear technology, then you can manufacture and process anything.’ (Ayacko, 2012). Development and SMRs could have a synergistic relationship, with potential for these small reactors to be as disproportionately important to developing countries as are mobile telephones and air travel.

This chapter will mention the ‘capabilities approach’ to human development, as a foundational concept; look at various characteristics of developing countries for which SMR deployment is suitable; and discuss development and some associated trade-offs that affect SMR deployment. Although this chapter affirms SMRs as a ‘counterfactual choice’ — what one would have chosen if one had the choice — for energy in developing countries, some alternative choices and potential consequences will be discussed.

The fulcrum of the argument is the opportunity cost incurred by the continued use of greenhouse gas (GHG)-emitting and costly fuels, once an SMR is viable for deployment in countries that disproportionately suffer the effects of climate change and lack energy security in the face of high and volatile fuel costs, while hampered by low income or high debt.

Looking ahead, some obstacles to SMR deployment, and innovations that could address them, will be identified. The chapter concludes on the need for a revised understanding of the wide context of SMR deployment and developing countries.

The most advanced of the Russian SMR designs is KLT-40S. A pilot barge-mounted plant with the two KLT-40S reactors named ‘Akademik Lomonosov’ has been licensed in the Russian Federation and is at the final stages of of construction (Kessides and Kuznetsov, 2012). The plan is to deploy it in a bay near the city of Pevek in the Chukotka region (north Russia) in 2016. Stress tests for the plant have been performed after the Fukushima Daiichi accident in Japan, which confirmed safety of the barge — mounted plant in its targeted deployment location. Subject to successful operation of the Akademik Lomonosov, five or seven similar plants of the same type may be deployed in the north and east regions of Russia. A number of customers in Russia have already confirmed their intention to host such plants.

Regarding the ABV reactor, its previous design version with a shorter core lifetime was licensed many years ago and work is in progress to develop and qualify a new core design with 12 years of continuous operation between refuelings. No decision has been made regarding the construction, but possible locations of barge-mounted plants with the twin ABV reactors may include deltas of the rivers or lakes in the north and east of Russia. Land-based ABV plants are also being considered (Sozonyuk, 2011).

For the RITM-200 design has been completed and approved by the State Atomic Energy Corporation ‘Rosatom’ by 2012 (Veshnyakov, 2011). Deployment of a new-generation ice-breaker with the twin RITM-200 units is scheduled for 2017. After deployment and operation of the ice-breaker the RITM-200 reactors could be considered for new generations of barge-mounted and land-based NPPs.

Detailed design development is in progress for the lead-bismuth cooled SVBR — 100. Decision has been made on the construction of a single-module prototype of this reactor at the site of the ‘State Scientific Centre — NIIAR’ in Dimitrovgrad (Russia) in 2017. Subject to successful operation of the prototype, deployment of single — or multi-module plants with SVBR-100 reactors could be considered. Development of SVBR-100 is indicated as a priority in the Russian Federal Program ‘Nuclear power technologies of new generation for the period 2010-2015 and for the future up to 2020’, emplaced by the RF Government Order No. 50.

Regarding UNITHERM, the deployment targets are not yet defined, although negotiations have been in progress for some time with potential customers in the Russian Yakutia region. The design stage is early conceptual design and the targeted customers are small settlements in the continental Y akutia and Siberia.

SHELF is at the earliest design stages and its deployment prospects are conditioned by the progress of the projects of gas recovery from the gas condensate deposits and oil mining from the bottom of the Arctic seas (IAEA, 2012c). No deployment date is currently available.

Table 17.7 gives the available designers’ data on the absolute overnight capital costs, on specific overnight capital costs and on levelized unit electricity costs of energy products (LUEC) for some of the SMRs presented in this chapter. For comparison, similar data for the state-of-the-art large plant with the VVER reactor (twin unit) is given.

As can be seen from Table 17.7, the specific overnight capital costs and the LUEC for SMRs are higher than for a large PWR (VVER-1150). However, they are well below the current tariffs for electricity in targeted locations (see Section 17.1). The absolute overnight capital costs, are always much smaller for SMRs than for an NPP with a large reactor (see Table 17.7).

All Russian SMRs are being designed to be licensed and deployed first in their country of origin — the Russian Federation — where they could cater to a variety of energy needs, specifically, in remote areas where electricity tariffs are currently much higher than on the mainland. In the case of success, after several years of operation at rated capacity factors, some of them could be considered for deployment in other countries. Specifically, barge-mounted plants could be offered to a number of other countries for the purposes of seawater desalination (to be performed by a desalination plant located on a separate barge) (Sozonyuk, 2011).

17.2 Future trends

In Russia, SMRs are not considered as possible competitors to large reactors. The overall idea is to have reactors of different capacities within a broad power range to cater to the needs of a variety of potential customers in the diverse energy demand, siting, transportation and climatic conditions throughout the country; see Section 17.1. This is at least, true for SMRs based on PWR technologies.

With more notable progress observed for barge-mounted plants, the first-of-a — kind plant Akademik Lomonosov with the two KLT-40S reactors is deemed to demonstrate the validity of technical solutions implemented in a barge-mounted NPP design concept and pave a way to future generations of such plants with newer, more advanced reactors. Such reactors may include future modifications of the RITM — 200, originally designed as an ice-breaker reactor, or a medium-sized VBER-300 of 300 MW(e) (Sozonyuk, 2011). For smaller barge-mounted plants, such as that with the twin ABV units, future options to install very small lead-bismuth-cooled reactors, e. g., SVBR-10 of 10 MW(e) (IAEA, 2010), are being considered.

Table 17.7 Cost data for SMRs SMR (Country) Unit power, MW(e) Overnight capital cost, US$ billion Overnight capital cost, US$/kW(e) LUEC US$ cent/ kW h, at a 5% discount rate Levelized heat cost US$/Gcal Levelized desalinated water cost US$ cent/m3 Russian PWR-type SMRs KLT-40S 2 X 35 0.259-0.294 3700-4200 4.9-5.3 21-23 85-95 ABV 2 X 8.5 0.155 9100 <12 <45 <160 RITM-200 2 X 50 0.330-0.370 3300-3700 n/a n/a n/a IEA/NEA projections for large LWRs, data taken from p. 59 of IEA/NEA-OECD (2010) VVER-1150 2 X 1070 6.276 2933 4.35 n/a n/a Sources: Based on data from pp. 68 and p. 170 of Current Status, Technical Feasibility and Economics of Small Nuclear Reactors (NEA-OECD, 2011); Kessides and Kuznetsov (2012) and IEA/NEA-OECD (2010).

Regarding ice-breaker reactors, development of a multi-purpose ice-breaker with the twin RITM-200 units will be followed by a development of the advanced, more powerful RITM series reactor for a larger nuclear ice-breaker of the leader class (Sozonyuk, 2011). SVBR-100 is one of the three fast reactor projects included in the Russian Federal Program ‘Nuclear power technologies of new generation for the period 2010-2015 and for the future up to 2020’ emplaced by the RF Government Order No. 50. The other two are commercial sodium-cooled fast reactor BN-1200 and lead-cooled fast reactor BREST-1200, both of 1200 MW(e), with BREST-1200 being preceded by a smaller prototype BREST-300 of 300 MW(e). By and around 2020, depending on the progress manifested by each of the three projects, a strategic decision on deployment targets for the selected fast reactor designs in the Russian Federation will be taken. In case of success, the SVBR-100 may be furthered for use within larger multi-module plants, the conceptual proposals for which are highlighted in IAEA (2007). Those could be 4 or even 16-module plants of the overall capacity as high as 1600 MW(e) and with a variety of co-generation options.

17.3 Conclusion

Owing to multi-year national experience in design, deployment and operation of marine propulsion reactors, including the reactors of nuclear ice-breakers, the Russian Federation is progressing well toward deployment of pilot SMRs of the pressurized — water type (for a barge-mounted NPP) and of the lead-bismuth-cooled type (with fast neutron spectrum). The deployments are expected before the end of the present decade. R&D on several other concepts is in progress along the technology lines mentioned above, as well as for high-temperature gas-cooled reactors.

In the Russian Federation small reactors are not viewed as direct competitors to large reactors. For small reactors, targeted are particular niche markets where electricity costs are high, where co-generation, long refueling interval or plant relocatability are assets, where transportation routes are seasonal, where the demand is limited and siting conditions are specific (i. e., no water in winter due to deep freezing of rivers or other water reservoirs). The layout of the country offers a variety of niche opportunities for such reactors in areas where tariffs for electricity are much higher than in the rest of the country. Export deployment of the Russian SMRs based NPPs will be considered after they have been deployed domestically and demonstrated the effectiveness of their technologies.

To offset the growing internal demand for fuels they produce and still maintain export volumes (Lee et al., 2012; Osabutey, 2012), countries with coal, oil, or gas resources may find small-scale nuclear useful as replacement.

SMR generation could provide power for industry outside the resource realm, contributing to diversified economic activity. The caveat exists that where countries are highly dependent on coal and petroleum industries, as for example Indonesia or Venezuela, an SMR program would need to be integrated into the existing economic structure. Their comparatively small size might more easily permit this.