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[en] The tax laws have greatly diminished the importance of utility preferred stock. But with utility construction programs expected to rise, it is an opportune time to see if preferreds can be an attractive option again. As recently as 1980, preferred stock financing by electric utilities comprised 55% of all U.S. corporate preferred stock issued. By 1989, this percentage had declined to under 12%. In dollar amounts, electric utility preferred stock financing had decreased by two-thirds over the same time period. The author analyzes just why this decline occurred and what it portends for the future
[en] Decisions throughout the life cycle of a building, from design through construction and commissioning to operation and demolition, require the involvement of multiple interested parties (e.g., architects, engineers, owners, occupants and facility managers). The performance of alternative designs and courses of action must be assessed with respect to multiple performance criteria, such as comfort, aesthetics, energy, cost and environmental impact. Several stand-alone computer tools are currently available that address specific performance issues during various stages of a building's life cycle. Some of these tools support collaboration by providing means for synchronous and asynchronous communications, performance simulations, and monitoring of a variety of performance parameters involved in decisions about a building during building operation. However, these tools are not linked in any way, so significant work is required to maintain and distribute information to all parties. In this paper we describe a software model that provides the data management and process control required for collaborative decision making throughout a building's life cycle. The requirements for the model are delineated addressing data and process needs for decision making at different stages of a building's life cycle. The software model meets these requirements and allows addition of any number of processes and support databases over time. What makes the model infinitely expandable is that it is a very generic conceptualization (or abstraction) of processes as relations among data. The software model supports multiple concurrent users, and facilitates discussion and debate leading to decision making. The software allows users to define rules and functions for automating tasks and alerting all participants to issues that need attention. It supports management of simulated as well as real data and continuously generates information useful for improving performance prediction and understanding of the effects of proposed technologies and strategies
[en] The paper presents a planning methodology using an application of a mathematical and a rule-based expert system (ES) to expand the transmission network in open access schemes. In this methodology, the ES suggests a realistic set of generation additions with proper economic signals to the participants, before proceeding with the transmission expansion. A feasible list of transmission alternatives is then assumed to accommodate the proposals for generation. A mathematical method is performed based on marginal cost allocation to optimise the location for the new generation and its transmission expansion scheme simultaneously for each alternative. The optimum alternative, which minimises the overall system's cost function and satisfies the future demand under different operating conditions, is obtained. The ES interacts with the power system planning tools to produce the optimum expansion plan. A practical application is given to demonstrate the effectiveness of the developed prototype system. (Author)
[en] Highlights: • Literature survey: An extensive review of the studies of household fuel use in developing countries. • Microeconomic theory requires considering a broad set of decisions beyond fuel use, and sometimes the consequences of missing markets. • A better account of observed and unobserved context and household heterogeneities and over time is necessary. • The main included factors are generally: income, age and education of the household head, and the fuel prices. • The main excluded factors are generally: non-fuel prices, agricultural activities and access to energy sources. - Abstract: Owing to recent concerns about the negative externalities of traditional fuel use on the environment and health, the issue of the household fuel transition in developing countries, from dirty fuels towards clean fuels, is receiving growing research attention. This paper provides an up-to-date survey of the economic literature on household fuel use in these countries. We first present the conceptual and theoretical frameworks. Then we discuss the empirical results that show the wide range of factors that drive the household fuel transition and can be understood better by linking them with theory.
[en] In the developing electricity market, many questions on electricity pricing and the risk modelling of forward contracts require the evaluation of the expected value and probability distribution of the short-run marginal cost of power generation at any given time. A concise forecasting method is provided, which is consistent with the definitions of marginal costs and the techniques of probabilistic production costing. The method embodies clear physical concepts, so that it can be easily understood theoretically and computationally realised. A numerical example has been used to test the proposed method. (author)
[en] A semiempirical model for the cost of a commercial plasma source ion implantation (PSII) facility is presented. Amortized capital and operating expenses are estimated as functions of the surface area throughput T. The impact of secondary electron emission and batch processing time is considered. Treatment costs are found to decrease monotonically with T until they saturate at large T when capital equipment payback and space rental dominate the expense. A reasonably sized PSII treatment facility should be able to treat a surface area of 104 m2 per year at a cost of $0.01 per cm2
[en] The concept and general principles of planned lifetime management (PLM) are described for optimising the total life-cycle cost of a plant or installation. The various components of PLM are described and definitions provided of the possible outputs of the corresponding techniques and tools. (UK)
[en] EMWG: Mandate and Membership: • Mandate: To develop methodology for assessment of Gen IV systems against GIF Economic Goals: → Life cycle cost advantage over other systems (lower LUEC); → Comparable financial risks (total capital investment cost (TCIC)). Extended mandate: → Maintain cognizance of challenges and opportunities for integration of Gen IV systems with renewables on the grid; → Methodologies for economic impact of integration; → R&D challenges to meet flexibility requirements. Current membership: Canada, China, France, Japan, Russia, South Africa, South Korea, the USA, IAEA (observer).
[en] When a unit is tested outside a technical system, it has normally been removed due to a fault. However, in some cases the external test may not discover any fault and a No Fault Found (NFF) event may occur. The NFF phenomenon is a major problem when dealing with complex technical systems, and its consequences may be manifested in decreased safety and dependability and increased life cycle costs. There are multiple interacting causes of NFF, demanding tough requirements for successful solutions. The purpose of this paper is to describe the phenomenon of NFF and to highlight possible improvements for the prevention of causes of NFF and the reduction of its consequences. The study was performed as an explorative literature study, and the analysis was based on a holistic system view. The identified causes and solutions are related to life cycle stages, availability performance factors, and system stakeholders