150 research outputs found
Tritium supply and use: a key issue for the development of nuclear fusion energy
Full power operation of the International Thermonuclear Experimental Reactor (ITER) has been delayed and will now begin in 2035. Delays to the ITER schedule may affect the availability of tritium for subsequent fusion devices, as the global CANDU-type fission reactor fleet begins to phase out over the coming decades. This study provides an up to date account of future tritium availability by incorporating recent uncertainties over the life extension of the global CANDU fleet, as well as considering the potential impact of tritium demand by other fusion efforts. Despite the delays, our projections suggest that CANDU tritium remains sufficient to support the full operation of ITER. However, whether there is tritium available for a DEMO reactor following ITER is largely uncertain, and is subject to numerous uncontrollable externalities. Further tritium demand may come from any number of private sector âcompact fusionâ start-ups which have emerged in recent years, all of which aim to accelerate the development of fusion energy. If the associated technical challenges can be overcome, compact fusion programmes have the opportunity to use tritium over the next two decades whilst it is readily available, and before full power DT operation on ITER starts in 2035. Assuming a similar level of performance is achievable, a compact fusion development programme, using smaller reactors operating at lower fusion power, would require smaller quantities of tritium than the ITER programme, leaving sufficient tritium available for multiple concepts to be developed concurrently. The development of concurrent fusion concepts increases the chances of success, as it spreads the risk of failure. Additionally, if full tritium breeding capability is not expected to be demonstrated in DEMO until after 2050, an opportunity exists for compact fusion programmes to incorporate tritium breeding technology in nearer-term devices. DD start-up, which avoids the need for external tritium for reactor start-up, is dependent upon full tritium breeding capability, and may be essential for large-scale commercial roll-out of fusion energy. As such, from the standpoint of availability and use of external tritium, a compact route to fusion energy may be more advantageous, as it avoids longer-term complications and uncertainties in the future supply of tritium
Towards Resilience to Nuclear Accidents:Financing Nuclear Liabilities via Catastrophe Risk Bonds
In light of the 2011 Fukushima disaster, recent discussion has focused on finding the best nuclear storage options, maximizing the oversight power of global institutions, and strengthening safety measures. In addition to these, the development of dependable liability coverage that can be tapped in an emergency is also needed and should be considered thoughtfully. To succeed, financing is essential using special-purpose instruments from the global bond market, which is as big as US$175Â trillion. Thus, in this paper, for the first time, a two-coverage-type trigger nuclear catastrophe (N-CAT) risk bond for potentially supplementing the covering of U.S. commercial nuclear power plants (NPPs) beyond the coverage per the Price Anderson Act as amended, and potentially other plants are proposed and designed worldwide. The N-CAT peril is categorized by three risk layers: incident, accident, and major accident. The pricing formula is derived by using a semi-Markovian dependence structure in continuous time. A numerical application illustrates the main findings of the paper.</jats:p
The role of the reactor size for an investment in the nuclear sector: an evaluation of not-financial parameters
The literature presents many studies about the economics of new Nuclear Power Plants (NPPs). Such studies are based on Discounted Cash Flow (DCF) methods encompassing the accounts related to Construction, Operation & Maintenance, Fuel and Decommissioning. However the investment evaluation of a nuclear reactor should also include not-financial factors such as siting and grid constraints, impact on the national industrial system, etc.
The Integrated model for the Competitiveness Assessment of SMRs (INCAS), developed by Politecnico di Milano cooperating with the IAEA, is designed to analyze the choice of the better Nuclear Power Plant size as a multidimensional problem. In particular the INCASâs module âExternal Factorsâ evaluates the impact of the factors that are not considered in the traditional DCF methods.
This paper presents a list of these factors, providing, for each one, the rationale and the quantification procedure; then each factor is quantified for the Italian case. The IRIS reactor has been chosen as SMR representative.
The approach and the framework of the model can be applied to worldwide countries while the specific results apply to most of the European countries. The results show that SMRs have better performances than LRs with respect to the external factors, in general and in the Italian scenario in particular
Small Modular Reactors: Licensing constraints and the way forward
SMR (Small Modular Reactor) is an acronym for a group of nuclear power plant designs receiving an increasing deal of attention from the industry and policy makers. A large number of SMRs need to be built in the same site and across the word to compensate diseconomies of scale and be cost competitive with large reactors and other base-load technologies. A major barrier is the licensing process, historically developed for large reactors, preventing the simply deployment of several identical units in different countries. This paper, discussing Ramana, Hopkins and Glaser [1], enlarges the view to all the SMR-related implications on the licensing process, presenting their legislative implications and market effects
Heavy metals and radioactivity reduction from acid mine drainage lime neutralized sludge
Abstract: The worldwide known treatment processes of acid mine drainage result into the formation of hydrous ferric oxides that is amorphous, poorly crystalline and into the generation of hazardous voluminous sludge posing threat to the environment. Applicable treatment technologies to treat hazardous solid material and produce useful products are limited and in most cases nonexistence. A chemical treatment process utilizing different reagents was developed to treat hazardous acid mine drainage (AMD) sludge with the objectives to conduct radioactivity assessment of the sludge generated from lime treatment process and determine the reagent that provides the best results. Leaching with 0.5 M citric acid, 0.4 M oxalic acid, 0.5 M sodium carbonate and 0.5 M sodium bicarbonate was investigated. The leaching time applied was 24 hours at 25 oC. The characterization of the raw AMD revealed that the AMD sludge from lime treatment process is radioactive. The sludge was laden with radioactive elements namely, 238U, 214Pb, 226Ra, 232Th, 40K and 214Bi. 0.5 M citric acid provided the best results and the hazardous contaminants were significantly reduced. The constituents in the sludge after treatment revealed that there is a great potential for the sludge to be used for other applications such as building and construction
Reply to Kasperski, Kuchinskaya and Josephson on âJ-value assessment of relocation measures following the nuclear power plant accidents at Chernobyl and Fukushima Daiichiâ
Cost overruns â helping to define what they really mean
Civil engineers are often in the firing line for alleged cost overruns, particularly on major publicly funded infrastructure projects. This usually occurs when the final cost of a project is simply compared with the original estimate, even though this was published a long time ago, in different circumstances and for a quite different project to the one carried out. This paper proposes a systematic approach to ensure that cost overruns, should they occur, are more accurately defined in terms of when the initial and end costs are assessed, from which point of view, at which project stage, and including scope changes and financial assumptions. The paper refers to the UKâs ÂŁ163 billion nuclear decommissioning programme
Exploring the role of phase-out policies for low-carbon energy transitions: the case of the German Energiewende
The energy sector plays a significant role in reaching the ambitious climate policy target of limiting the global temperature increase to well below 2°C. To this end, technological change has to be redirected and accelerated in the direction of zero-carbon solutions. Given the urgency and magnitude of the climate change challenge it has been argued that this calls for a policy mix which simultaneously supports low-carbon solutions and also deliberately drives the discontinuation of the established technological regime. Yet, the effect of such phase-out policies on the development and diffusion of low-carbon technologies has received little attention in empirical research so far. This paper addresses this gap by taking the case of the transition of the German electricity generation system towards renewable energies â the so-called Ener-giewende. Based on a survey of innovation activities of German manufacturers of renewable power gener-ation technologies conducted in 2014 it explores the impact such destabilization policies â most prominent-ly Germanyâs nuclear phase-out policy â may have on technological change in renewable energies. By drawing on descriptive statistics and combining insights from earlier regression analyses we find evidence that Germanyâs nuclear phase-out policy had a positive influence on manufacturersâ innovation expendi-tures for renewable energies and was seen as the by far most influential policy instrument for the further expansion of renewable energies in Germany. The insights resulting from our explorative analysis have important implications for the literature on policy mixes and sustainability transitions regarding the âflip sidesâ to innovation and the crucial importance of destabilization policies for unleashing âdestructive crea-tionâ. We close by discussing policy repercussions for ongoing debates on policies for accelerating the phase-out of coal to meet climate change targets
Chapter 20 Assessment of radiation pollution from nuclear power plants
Nuclear power plants split uranium atoms in a process called fission. In a nuclear power plant, heat is generated to produce steam that spins a turbine to generate electricity. Nuclear energy has been proposed in response to the need for a clean energy source compared to CO2 production plants. However, nuclear energy is not necessarily a source of clean energy as nuclear power plants release small amounts of greenhouse emissions in activities related to building and running the plant. Moreover, even if all safety measures are followed, there is no guarantee that an accident will not occur in a nuclear power plant. In the case of an accident involving a nuclear power plant, the environment and the people around it may be exposed to high levels of radiation. Another important environmental problem related to nuclear energy is the generation of radioactive waste that can remain radioactive and dangerous to human health for thousands of years. There are also several issues with burying the radioactive waste. Here, we describe different types of radioactive waste pollution from nuclear power plants, their environmental effects, nuclear regulations, and nuclear power plant incidents. Moreover, two case studies on nuclear power plant accidents and their consequences are discussed
A systematic review of the impacts of climate variability and change on electricity systems in Europe
Understanding the impacts of climate variability and change (CV&C) on electricity systems is paramount for operators preparing for weather-related disruptions, policymakers deciding on future directions of energy policies and European decision makers shaping research programs. This study conducted a systematic literature review to collate consistent patterns of impacts of CV&C on electricity systems in Europe. We found that, in the absence of adaptation and for current capacity, thermal electricity generation will decrease for the near term to mid-21st century (NT-MC) and the end of the 21st century (EC). In contrast, renewable electricity generation will increase for hydroelectricity in Northern Europe (NT-MC and EC), for solar electricity in Germany (NT-MC) and the United Kingdom and Spain (NT-MC and EC) and for wind electricity in the Iberian Peninsula (NT-MC) and over the Baltic and Aegean Sea (NT-MC and EC). Although the knowledge frontier in this area has advanced, the evidence available remains patchy. Future assessments should not only address some of the gaps identified but also better contextualise their results against those of earlier assessments. This review could provide a starting point for doing so
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