[en] Energy environmental and economical systems do not allow for experimentation since this would be dangerous, too expensive or even impossible. Instead, mathematical models are applied for energy planning. Experimenting is replaced by varying the structure and some parameters of 'energy models', computing the values of depending parameters, comparing variations, and interpreting their outcomings. Energy models are as old as computers. In this article the major new developments in energy modeling will be pointed out. We distinguish between 3 reasons of new developments: progress in computer technology, methodological progress and novel tasks of energy system analysis and planning

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[en] Dark energy models which alter the relative scaling behavior of dark energy and matter could provide a natural solution to the cosmic coincidence problem -- why the densities of dark energy and dark matter are comparable today. A generalized class of dark energy models is introduced which allows noncanonical scaling of the ratio of dark matter and dark energy with the Robertson-Walker scale factor a(t) . We show that determining whether there is a coincidence problem, and the extent of cosmic coincidence, can be addressed by several forthcoming experiments

[en] In this paper, we specify and estimate a two-level integrated total energy demand model for the Province of Quebec. The specification of the model has a close relationship with models currently used by Canadian public agencies to perform policy simulations and to make forecasts. The focus of the analysis is on forecasting. Two forecasting experiments are conducted while using within sample data. In the first experiment, we establish one-year forecasts, while in the second the model is solved recursively over the whole sample, which consists of annual data from 1962 to 1990. It is found that the model has good tracking properties and that most of the forecasting errors are random. The forecasting experiments show no significant structural defects of the estimated model as a forecasting tool. (author)

[en] The process of introduction of a new technology supposes that while its production and utilisation increases, also its operation improves and its investment costs and production decreases. The accumulation of experience and learning of a new technology increase in parallel with the increase of its market share. This process is represented by the technological learning curves and the energy sector is not detached from this process of substitution of old technologies by new ones. The present paper carries out a brief revision of the main energy models that include the technology dynamics (learning). The energy scenarios, developed by global energy models, assume that the characteristics of the technologies are variables with time. But this trend is incorporated in a exogenous way in these energy models, that is to say, it is only a time function. This practice is applied to the cost indicators of the technology such as the specific investment costs or to the efficiency of the energy technologies. In the last years, the new concept of endogenous technological learning has been integrated within these global energy models. This paper examines the concept of technological learning in global energy models. It also analyses the technological dynamics of the energy system including the endogenous modelling of the process of technological progress. Finally, it makes a comparison of several of the most used global energy models (MARKAL, MESSAGE and ERIS) and, more concretely, about the use these models make of the concept of technological learning. (Author) 17 refs

[en] The effective coefficient of attenuation of macroseismic intensity with distance is studied for the Racha earthquake region. The study is based on macroseismic data on the Racha earthquake of April 29, 1991. The Blake-Shebalin formula for macroseismic field was used. Proceeding from the energy model of the earthquake focus, we consider the intensity for point, linear and volumetric foci. (authors)

[en] This text contains a detailed analysis of the most difficult problems in pricing electricity, including: price modelling, derivative valuation, feedstock correlations, and weather risk. The book also relates key modelling difficulties to practical strategies for risk management. (Author)

[en] In numerous recently deregulated energy markets, utilities previously operating in monopolistic environments are now focusing on customer satisfaction and loyalty. In this study, a conceptual framework is proposed that analyses the effects of brand associations and perceived switching costs on customer satisfaction and loyalty in residential energy markets. Several brand associations relevant to energy branding are identified: perceived technical service quality and service process quality, perception of value-added services, environmental and social commitment of the company, brand trust, price perceptions and brand associations related to the corporate attributes 'innovative and dynamic'. Subsequently, the proposed model is tested in the scope of a representative survey of Spanish residential energy customers. Results indicate that customer satisfaction, brand trust and perceived switching costs are positively related to customer loyalty and that brand trust exerts a stronger influence on customer loyalty than satisfaction and switching costs. Findings also show significant effects of the perception of service process quality and environmental and social commitment on loyalty via customer satisfaction. Implications for energy brand managers and regulators are discussed. [Author]

[en] The role of energy in the production of manufacturing output has been debated extensively in the literature, particularly its relationship with capital and labor. In an attempt to provide some clarification in this debate, a two-step methodology was used. First under the assumption of a five-factor production function specification, we distinguished between electric and non-electric energy and assessed each component's relationship with capital and labor. Second, we calculated both the Allen and price elasticities and constructed 95% confidence intervals around these values. Our approach led to the following conclusions: that the disaggregation of the energy input into electric and non-electric energy is justified; that capital and electric energy and capital and non-electric energy are substitutes, while labor and electric energy and labor and non-electric energy are complements in production; and that capital and energy are substitutes, while labor and energy are complements. (author)

[en] The recently proposed multicanonical simulation technique which can be used in a wide variety of fields from high energy to condansed matter physics, from biophysics to optimization is applied here to spin systems. For the purpose of investigating the spin systems with complexity under conflicting constraints, whose number of properties can not be studied by canonical techniques, multicanonical simultation of the Hopfield model of neural networks is performed. The histograms of the order parameters are obtained in the ferromagnetic, paramagnetic and the spin glass phase regions of the replica symmetric mean field solution. Physical quantities are evaluated for any value of temperature from only one simulation following fixing the multicanonical parameters by recursive techniques and thermalization. Ground state energy and entropy densities are studied and their limiting values are obtained by finite size scaling. Advantages of the multicanonical technique is examined and comparison to the standart canonical simulation also considered