Future Nuclear Power Research Articles

Design and development of the AHWR—the Indian thorium fuelled innovative nuclear reactor

India has chalked out a nuclear power program based on its domestic resource position of uranium and thorium. The first stage started with setting up the Pressurized Heavy Water Reactors (PHWR) based on natural uranium and pressure tube technology. In the second phase, the fissile material base will be multiplied in Fast Breeder Reactors using the plutonium obtained from the PHWRs. Considering the large thorium reserves in India, the future nuclear power program will be based on thorium– 233U fuel cycle. However, there is a need for the timely development of thorium-based technologies for the entire fuel cycle. The Advanced Heavy Water Reactor (AHWR) has been designed to fulfill this need. The AHWR is a 300 MW e, vertical, pressure tube type, heavy water moderated, boiling light water cooled natural circulation reactor. The fuel consists of (Th–Pu)O 2 and (Th– 233U)O 2 pins. The fuel cluster is designed to generate maximum energy out of 233U, which is bred in situ from thorium and has a slightly negative void coefficient of reactivity. For the AHWR, the well-proven pressure tube technology has been adopted and many passive safety features, consistent with the international trend, have been incorporated. A distinguishing feature which makes this reactor unique, from other conventional nuclear power reactors is the fact that it is designed to remove core heat by natural circulation, under normal operating conditions, eliminating the need of pumps. In addition to this passive feature, several innovative passive safety systems have been incorporated in the design, for decay heat removal under shut down condition and mitigation of postulated accident conditions. The design of the reactor has progressively undergone modifications and improvements based on the feedbacks from the analytical and the experimental R&D. This paper gives the details of the current design of the AHWR.

Nuclear nonproliferation and the future expansion of nuclear power

This paper examines the relationships between the future expansion of nuclear power and the prospect for world nuclear nonproliferation. For this purpose, recent changes and developments in international political environment, nonproliferation regimes, business practices surrounding civilian nuclear power industry, and technological advancements were examined. Based on these examinations, the paper attempts to answer the question, “What should be done for future nuclear power development not to result in further increase in proliferation risk?”

On nuclear power intrinsically protected against long-lived actinide wastes, weapons proliferation and heavy accidents

The “Mobile fuel reactor (MFR) concept” [Slessarev, I., Stukalov,V., Subbotin, S., 1984. Problems of development of fast reactors self-fuel-provision without fuel reprocessing. Atomkernenergie, 45, N1; Slessarev, I., et al., 2004. WISE: a new fuel cycle concept based on a mobile fuel reactor. Nuclear Technol., 146 (N3), 230–243] and re-organization of the fuel cycle may allow to build the “actinide waste free” nuclear power (NP) and to improve radically its proliferation resistance. These goals can be achieved on the base of an “intrinsic approach” respecting long-lived wastes, safety and non-proliferation aspects simultaneously. It implies elimination of feed fuel enrichment, irradiated fuel reprocessing as well as the need for a long-lived, radiotoxic actinide repository. The key concept is: the application of “mobile” (liquid or gaseous) reactor fuels allowing for a simple mixing of fresh and already irradiated fuel components without “forced” FP separation. The neutronics of the innovative nuclear reactor concept, -MFR- with mobile fuels is discussed in details. Elimination of fuel enrichment implies “natural fuel” feed with relatively low neutron balance potential, however, the neutronics has to be capable of supporting critical or near-critical regimes to be economically acceptable. Sufficient capability is achieved by utilizing a favorable, hard neutron spectrum (e.g. fast neutron spectrum of SPX-type), in addition to elongation of the fuel in-core residence time and by use of an appropriate core composition with enhanced fissile breeding. No dedicated actinide transmutation (by targets for example) is required in this system. It is concluded that the mobile fuel reactor neutronics in the case of the once-through fuel cycle is almost acceptable to be used for future NP to be protected intrinsically against long-lived actinide wastes, weapons proliferation menace and heavy accidents.

Scenarios for a worldwide deployment of nuclear power

The growing worldwide demand for energy must be controlled. However, even in the event of voluntary policies to dampen energy demand, it is hard to imagine that the demand could be less than twice as much as today's by 2050. We feel it is necessary to satisfy this demand. It is obvious also that greenhouse gas emissions must be reduced in order to limit the severe consequences that they entail. An energy shortage could develop if new sources of large-scale energy production are not established. A significant contribution of nuclear power to such energy production by 2050 rests on a well-coordinated and optimised deployment scheme (Loiseaux et al., 2004; The Future of Nuclear Power, 2003). This requires, as early as today, a reflection on the present status of nuclear power, on its extrapolation into the future and, thus, on the means that should be put to work and the transition possibilities.

Future of nuclear power in Europe

This paper reviews the current state of nuclear energy programmes and investment and some other energy issues, and concludes that nuclear energy is indispensable and a better option than the continued problem of global warming.

Risky Business: Nuclear Power and Public Protest in Canada

Chapter 1 Introduction: The Democracy-Technocracy Quandary Chapter 2 Risk Assessment in the Public Policy Domain Chapter 3 Nuclear Power and Public Protest Chapter 4 The Canadian Nuclear Industry Chapter 5 The Battle Over the Pickering Nuclear Generating Station Chapter 6 David and Goliath Meet on the Shore of Lake Ontario Chapter 7 The Future of Nuclear Power in Canada

Fuel Design and Core Layout for a Gas-Cooled Fast Reactor

The gas-cooled fast reactor (GCFR) is regarded as the primary candidate for a future sustainable nuclear power system. In this paper a general core layout is presented for a 2400-MW(thermal) GCFR. Two fuel elements are discussed: a TRISO-based coated particle and the innovative hollow sphere concept. Sustainability calls for recycling of all minor actinides (MAs) in the core and a breeding gain close to unity. A fuel cycle is designed allowing operation over a long period, requiring refueling with 238U only. The evolution of nuclides in the GCFR core is calculated using the SCALE system (one-dimensional and three-dimensional). Calculations were done over multiple irradiation cycles including reprocessing. The result is that it is possible to design a fuel and GCFR core with a breeding gain around unity, with recycling of all MAs from cycle to cycle. The burnup reactivity swing is small, improving safety. After several fuel batches an equilibrium core is reached. MA loading in the core remains limited, and the fuel temperature coefficient is always negative.

Analysis of future nuclear power plants competitive investment costs with stochastic methods

Abstract One of main issues in planning future power system expansion is forecast of expected electricity generating costs. Due to the fact that the forecast should be extended to plants lifetime it is best to consider and compare lifetime levelized cost of generated electricity for each of the candidate plants. The analysis is a part of studies for the future expansion of the Croatian power system, but is valid generally. The main competitors to nuclear power plants are combined cycle natural gas fired plants whose economy strongly depends upon gas cost. The expected increase of gas cost in following decades can substantially influence the competitiveness of nuclear plants versus gas fired plants. In addition, the costs of electricity produced by coal fired plants and wind electricity generators were also considered. Due to uncertainties of input parameters it is advantageous to use probabilistic instead of deterministic method of analysis. The paper considers the problem of the probabilistic distribution of nuclear power plant investment costs for which such plants could be competitive to gas fired plants for an estimated probable range of gas cost increase rates.

Environmental release targets for fusion power plants

Within the European fission community, so called European Utility Requirements were developed to define common targets, criteria and evaluation methods for, amongst others, safety, environmental protection and public health with respect to future nuclear fission power plant development. In the case of severe accidents, the objective is to restrict the radiological consequences to the vicinity of the plant, i.e., to avoid early and late countermeasures such as evacuation or relocation of the population, and to restrict food banning to small areas and the first year after the accident. Within the European Fusion Technology Programme, a methodology is being developed in compliance with these European Utility Requirements, to define design requirements for future fusion reactors. First results are presented. Concerning food banning, calculations revealed extremely conservative values for tritium in EU regulations and recommendations. This does not affect assessments for fission reactors, but is an overestimation of the tritium dose impact from ingestion. Therefore, in compliance with scientific justification, considerably higher maximum permissible activity levels for tritium should be considered.

The zero-waste option for nuclear fusion reactors: Advanced fuel cycles and clearance of radioactive materials

This paper deals with the radioactive waste issue for fusion reactors, proposing an innovative solution (the “zero-waste” option), which could be a clear advantage of fusion power versus fission, in view of its ultimate safety and public acceptance. Its goal is the Clearance (declassification to non-radioactive materials) of all reactor components, after a sufficient period of interim decay, according to the recommendations recently issued by IAEA. Even if feasible in theory, a zero-waste option for fusion reactors using the Deuterium–Tritium fuel cycle will be difficult to obtain in practice: a relevant amount of radioactive materials from reactor decommissioning – even if recyclable within the nuclear industry – should be disposed of as low-level waste. As a further step towards the zero-waste option, the features of fusion reactors based on alternative advanced fuel cycles have been examined, to assess whether that goal could be reached for such devices. Fusion reactors with advanced Deuterium–Helium-3 (DHe) fuel cycle have quite outstanding environmental advantages. Compact ignition tokamaks can be designed in order to achieve DHe ignition. Ignitor, a compact ignition experiment aimed at studying DT plasmas, may also be used in that direction. The extrapolation of Ignitor technologies towards a larger and more powerful experiment using advanced fuel cycles (Candor) is described. Results show that Candor does reach the zero-waste option. A fusion power reactor based on the DHe cycle could be the ultimate correct response to the environmental requirements for future nuclear power plants.

The future of nuclear power

The future of nuclear power

Parametric studies on different gas turbine cycles for a high temperature gas-cooled reactor

The high temperature gas-cooled reactor (HTGR) coupled with turbine cycle is considered as one of the leading candidates for future nuclear power plants. In this paper, the various types of HTGR gas turbine cycles are concluded as three typical cycles of direct cycle, closed indirect cycle and open indirect cycle. Furthermore they are theoretically converted to three Brayton cycles of helium, nitrogen and air. Those three types of Brayton cycles are thermodynamically analyzed and optimized. The results show that the variety of gas affects the cycle pressure ratio more significantly than other cycle parameters, however, the optimized cycle efficiencies of the three Brayton cycles are almost the same. In addition, the turbomachines which are required for the three optimized Brayton cycles are aerodynamically analyzed and compared and their fundamental characteristics are obtained. Helium turbocompressor has lower stage pressure ratio and more stage number than those for nitrogen and air machines, while helium and nitrogen turbocompressors have shorter blade length than that for air machine.

Science, Politics and Ethics in the Low Dose Debate

The roles of science, ethics and politics are identified in respect of the risks of exposure to low-dose radiation. Two case studies, the epidemiology of the United Kingdom nuclear test veterans and the risks to civilians associated with the military use of depleted uranium, are considered in the context of their ethical framing, scientific evaluation and political resolution. Two important issues for the present and future, the safe management of UK radioactive waste and the future of nuclear power, in which the science of low dose effects will be crucial and where the ethical issues are much more complex, are introduced. Specific consideration is given to the potential hereditary effects of ionising radiation in relation to the current state of radiobiological knowledge. It is concluded that for science to be useful in public health policy making there needs to be some reform from within the profession and the political imperative for freely independent scientific institutions.

Past and present research in europe on the production of nuclear hydrogen with HTGR

The High-Temperature Gas-Cooled Reactor represents a suitable concept of a future nuclear power plant with efficient and economic and safe generation of energy. Its potential to produce process heat at high temperatures can be utilized in many industrial processes for the generation of hydrogen or other synthetic chemical fuels, which may find broadening application on the future world energy markets. The paper includes a description of the German long-term projects “Prototype Nuclear Process Heat Reactor Project” (PNP), in which the technical feasibility of an HTGR in combination with coal gasification processes has been proven, and “Nuclear Long Distance Energy Transportation” (NFE), a verification and demonstration of the closed-cycle, energy transmission system EVA/ADAM. But also the new research activities in Europe encouraged and supported by the Commission of the European Union within their Framework Programmes will be outlined. The Michelangelo Network (MICANET) has been created in 1997 by 19 European partners to elaborate a general European R&D strategy for the further development of the nuclear industry with a strong focus on innovative nuclear reactor designs. The Hydrogen Network (HYNET) established in 1999 is working on the development of strategies for the introduction of a European hydrogen fuel infrastructure. Both networks are paving the way for subsequent proposals for EU supported research projects such as V/HTR, HYSAFE, INNOHYP.

Underpinning the future of nuclear power

Underpinning the future of nuclear power

Potential of light-water reactors for future nuclear power plants

Potential of light-water reactors for future nuclear power plants

Editorial: Physics, Honesty, and Cooperation

This editorial is prompted by the recent discussions in Europe about the siting of the next generation plasma fusion experiment and the report of an interdisciplinary MIT study of "The Future of Nuclear Power" (http://www.mit.edu/afs/athena/org/n/nuclearpower/). I am struck by the different motivations involved in these two very dissimilar subjects which are only joined by their stated desire to produce cheap, clean, safe, and widely available electrical power for mankind. Plasma fusion is a very long-term aim. Indeed it seems to be permanently 50 years away. The MIT analysis of Nuclear power, in contrast, seems to be a hardheaded analysis of the realities facing this mode of electricity production.

Cancer risks attributable to low doses of ionizing radiation: assessing what we really know.

High doses of ionizing radiation clearly produce deleterious consequences in humans, including, but not exclusively, cancer induction. At very low radiation doses the situation is much less clear, but the risks of low-dose radiation are of societal importance in relation to issues as varied as screening tests for cancer, the future of nuclear power, occupational radiation exposure, frequent-flyer risks, manned space exploration, and radiological terrorism. We review the difficulties involved in quantifying the risks of low-dose radiation and address two specific questions. First, what is the lowest dose of x- or gamma-radiation for which good evidence exists of increased cancer risks in humans? The epidemiological data suggest that it is approximately 10-50 mSv for an acute exposure and approximately 50-100 mSv for a protracted exposure. Second, what is the most appropriate way to extrapolate such cancer risk estimates to still lower doses? Given that it is supported by experimentally grounded, quantifiable, biophysical arguments, a linear extrapolation of cancer risks from intermediate to very low doses currently appears to be the most appropriate methodology. This linearity assumption is not necessarily the most conservative approach, and it is likely that it will result in an underestimate of some radiation-induced cancer risks and an overestimate of others.

Safety Analysis of Fast Reactor Core with Uranium-Free Fuel for Actinide Transmutation

The solving of ecological problems of future nuclear power is connected with the solving of long-lived radioactive waste utilization problems. This concerns primarily plutonium and minor actinides (neptunium, americium, and curium), accumulated in the spent fuel of nuclear reactors. One of the ways this can be solved is to use a fast reactor with uranium-free fuel. The physics of this type of reactor was widely investigated during the last year for the BN-800 reactor. The solutions of the most important problems were (a) a decrease in nonuniformity of the power distribution and (b) an increase of the Doppler effect. The next stage of such core investigations is an evaluation of self-protection to beyond-design accidents. Preliminary results show a high safety level of the BN-800 reactor with uranium-free fuel in unprotected loss-of-flow and unprotected transient overpower events.

Natural gas in croatia's energy-future

World energy crises, the impending decline of fossil-fuel supplies and uncertainty of nuclear power's future have increased interest in renewable natural-energy sources. But, nevertheless, none of them is expected to take up the role of oil and natural gas in the near future. Global natural-gas supplies should be sufficient for at least 60 years. Croatia produces and utilises the following primary-energy sources: coal, fuel wood, crude oil, natural gas and hydropower. Natural gas will be promoted through the development and liberalisation of the energy market: its unit price and environmental considerations render it suitable for wide use to provide heat. Its greater utilisation (so displacing other fossil fuels) could dramatically improve environmental conditions in Croatia.