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[en] The development of high efficiency transformers is outlined and linked to the energy shortage of the late 1970s and the consequent upward revision of loss evaluation factors by electric utilities. The factors affecting power losses in transformers are briefly discussed. Core loss (no-load loss) depends on such factors as flux density, core weight, and materials, and is closely interrelated with load loss, which depends on the number of turns in the transformer coil, coil length, and current density. Some loss evaluation formulas in use are illustrated. Manufacturers have responded to these formulas by producing transformers with larger cores and lower flux densities, causing the no-load loss to be lower. The transformers are larger and more expensive to purchase. However, by considering the effects of evaluated losses plus the cost of the transformer, the total owning cost of these new designs is lower than that of previous low-cost, high-loss designs. The user who buys on price alone will get a transformer with the highest losses possible. 2 figs., 1 tab
[en] The underlying key to developing successful estimates, tracking project costs, and utilizing historical project cost information is the development of standardized and well-defined hierarchical listing of cost categories. Committees within the U.S. Federal agencies have pioneered efforts toward developing the Environmental Cost Element Structure (ECES), which is key in achieving these goals. The ECES was developed using an iterative process with input from federal agencies and industry. Experts from several disciplines participated including engineers, cost estimators, project/program managers, and contract personnel. The ECES benefits from an intense analytical effort, the knowledge gained from the maturation of the environmental industry, and incorporation of past user's experiences. Building upon this foundation, the E06 committee of the ASTM International has now fully developed and published a standard (ASTM 2150-04) that provides standardized cost categories with complete cost category definitions. This standard affords environmental and nuclear D and D project managers the opportunity to have a well defined hierarchical listing of their estimates and actual costs, readily adapted to performing summations and roll-ups, supported by a multi-level dictionary specifically defining the content of the cost elements as well as the summations. Owing to the dynamic nature of the environmental technologies, efforts need to be made to continue to update this standard by adding new technologies and methods as they are developed and employed in the field. Lastly, the Environmental Cost Element Structure that is embodied in this standard also presents opportunities to develop historical cost databases and comprehensive life cycle cost estimates and standardized cost estimating tools. (authors)
[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
[en] Depending on the real applications, there are various approaches to calculate the fuel cycle costs. The selection of methodology may depend on the required accuracy, for example, or on the drequired input data, or on the period to be covered, extending for example either over the entire commercial life of a nuclear power plant, or only over one equilibrium cycle. The paper discusses some of the most frequently approaches, showing any given or plannable connections between the various approaches. (Orig./DG)
[de]Je nach Anwendungsfall gibt es unterschiedliche methodische Ansaetze zur Berechnung der Brennstoffkreislaufkosten (BKK). Die Wahl der Methode kann z.B. durch die gewuenschte Genauigkeit bzw. den damit verbundenen Aufwand an Eingabedaten bedingt sein oder auch durch den gewuenschten Betrachtungszeitraum, wie z.B. Berechnung der BKK fuer die gesamte kommerzielle KKW Lebensdauer oder nur fuer einen Gleichgewichtszyklus. Im folgenden werden zunaechst einige der gebraeuchlichsten methodischen Ansaetze angesprochen. Dabei wird auch gezeigt, wie die verschiedenen Ansaetze miteinander zusammenhaengen bzw. miteinander in Verbindung gebracht werden koennen. (orig./DG)
[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] In life-cycle costing analyses, optimal design is usually achieved by minimising the expected value of the discounted costs. As well as the expected value, the corresponding variance may be useful for estimating, for example, the uncertainty bounds of the calculated discounted costs. However, general explicit formulas for calculating the variance of the discounted costs over an unbounded time horizon are not yet available. In this paper, explicit formulas for this variance are presented. They can be easily implemented in software to optimise structural design and maintenance management. The use of the mathematical results is illustrated with some examples
[en] A study was sponsored by FEMP in 2001 - 2002 to develop methods to compare life-cycle costs of federal energy conservation projects carried out through energy savings performance contracts (ESPCs) and projects that are directly funded by appropriations. The study described in this report follows up on the original work, taking advantage of new pricing data on equipment and on $500 million worth of Super ESPC projects awarded since the end of FY 2001. The methods developed to compare life-cycle costs of ESPCs and directly funded energy projects are based on the following tasks: (1) Verify the parity of equipment prices in ESPC vs. directly funded projects; (2) Develop a representative energy conservation project; (3) Determine representative cycle times for both ESPCs and appropriations-funded projects; (4) Model the representative energy project implemented through an ESPC and through appropriations funding; and (5) Calculate the life-cycle costs for each project.
[en] This article shows the economic viability or competitiveness of nuclear energy. The key costs of nuclear energy are fully internalized, that is, included in the prices for which electricity is sold. This includes radioactive waste disposal, decommissioning and most of the consequences of serious accidents. Today economic models indicate that the environmental cost of carbon emitted is of the order of 100 dollars per ton of carbon. Such a cost if internalized in fossil energy costs would make nuclear energy yet more attractive. (A.C.)
[en] The subject pertains to the implementation of the full range of subsurface uncertainties in life cycle probabilistic forecasting and its extension to project cash flows using the methodology of probabilities. A new tool has been developed in the probabilistic application of Crystal-Ball which can model reservoir volumetrics, life cycle production forecasts and project cash flows in a single environment. The tool is modular such that the volumetrics and cash flow modules are optional. Production forecasts are often generated by applying a decline equation to single best estimate values of input parameters such as initial potential, decline rate, abandonment rate etc -or sometimes by results of reservoir simulation. This new tool provides a means of implementing the full range of uncertainties and interdependencies of the input parameters into the production forecasts by defining the input parameters as probability density functions, PDFs and performing several iterations to generate an expectation curve forecast. Abandonment rate is implemented in each iteration via a link to an OPEX model. The expectation curve forecast is input into a cash flow model to generate a probabilistic NPV. Base case and sensitivity runs from reservoir simulation can likewise form the basis for a probabilistic production forecast from which a probabilistic cash flow can be generated. A good illustration of the application of this tool is in the modelling of the production forecast for a well that encounters its target reservoirs in OUT/ODT situation and thus has significant uncertainties. The uncertainty in presence and size (if present) of gas cap and dependency between ultimate recovery and initial potential amongst other uncertainties can be easily implemented in the production forecast with this tool. From the expectation curve forecast, a probabilistic NPV can be easily generated. Possible applications of this tool include: i. estimation of range of actual recoverable volumes based on pragmatic technical and economic considerations, ii. providing good risk assessment of ullage, iii. green field forecasts (eg. exploration wells), iv. estimating future cash flows uncertainty for large projects and v. strategic decision making (eg. impact of oil price)