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1.
This paper presents an assessment of energy performance in South Africa from 1965 to 2014 using the technique for order of preference by similarity to ideal solution (TOPSIS). In this research, TOPSIS is used first in a two-stage approach to assess how energy in South Africa has performed using the most frequent indicators adopted by the literature. Afterwards, in the second stage, neural networks are combined with TOPSIS results as part of an attempt to produce a model for energy performance with good predictive ability. The results reveal different impacts of contextual variables such as the rise of China in foreign trade, the Apartheid Regime, and oil shocks on energy performance in South Africa.  相似文献   

2.
In recent years, coal price has risen rapidly, which has also brought a sharp increase in the expenditures of thermal power plants in China. Meantime, the power production price and power retail price have not been adjusted accordingly and a large number of thermal power plants have incurred losses. The power industry is a key industry in the national economy. As such, a thorough analysis and evaluation of the economic influence of the electricity price should be conducted before electricity price adjustment is carried out. This paper analyses the influence of coal price adjustment on the electric power industry, and the influence of electricity price adjustment on the macroeconomy in China based on computable general equilibrium models. The conclusions are as follows: (1) a coal price increase causes a rise in the cost of the electric power industry, but the influence gradually descends with increase in coal price; and (2) an electricity price increase has an adverse influence on the total output, Gross Domestic Product (GDP), and the Consumer Price Index (CPI). Electricity price increases have a contractionary effect on economic development and, consequently, electricity price policy making must consequently consider all factors to minimize their adverse influence.  相似文献   

3.
Due to lower temperature requirements than other thermochemical cycles, the copper-chlorine (Cu–Cl) cycle is one of the most promising cycles for hydrogen production. The cycle consists of a number of endothermic and exothermic processes. The overall efficiency of the cycle can be improved by recovering as much heat as possible from the exothermic processes within the cycle and minimizing the net heat input to the cycle. In this paper, a pinch methodology is used to determine the minimum energy requirement for the overall Cu–Cl cycle, if heat recovery within the cycle is optimized. All heating and cooling flows (actual or potential) are presented as temperature-energy flow profiles and combined into composite curves for the entire cycle. Additional equipment and the overall thermal layout of the cycle are also investigated.  相似文献   

4.
The green electricity market is rapidly developing on an international scale, with an ever-increasing concentration of trade at the EU level. In this article Geert Palmers, of 3E NV in Belgium presents his viewpoint on the market mechanisms necessary to prepare for this international trade, while maintaining the subsidiarity at the demand side of the market, and maintaining the ambitions of a recent EU White Paper on this subject.  相似文献   

5.
The aim of this paper is to analyse the changes in final energy consumption in Andalusia through logarithmic mean Divisia index (LMDI) decomposition analysis during the period 2003–2012. The results lead us to conclude that a reduction of final energy (FE) consumption of 1 % took place as a result of a diminishing in structural effect by 11 % and an increase in the activity effect and intensity effect by 7.4 and 3.5 %, respectively. Chain-linked LMDI decomposition shows the existence of two sub-periods, with a turning point in 2008. The first period, coinciding to a great extent with the Andalusian Energy Plan 2003–2006 (PLEAN), showed an increase in final energy consumption, mostly due to the activity effect but also to the intensity effect. The second period, coinciding with the implementation of the Andalusian Sustainable Energy Plan 2007–2013 (PASENER), shows a reduction in the activity, structure and intensity effects. The results allow us to conclude that many of the energy efficiency measures, implemented through the PASENER, are related to sectors that experienced a decline in energy consumption due to the intensity effect, such as transport, primary and service sectors. Additionally, although they were included in PASENER, more policy attention should be given to the energy transformation, residential and industrial sectors which increased the demand for energy due to the intensity effect during this period. Finally, the energy-saving behaviour of economic agents due to the economic downturn should also be considered as an explanation for the diminishing in energy consumption during this sub-period.  相似文献   

6.
Given the booming economic growth and urbanization in China, cities have become crucial to sustaining this development and curbing national emissions. Understanding the key drivers underlying the rapid emissions growth is critical to providing local solutions for national climate targets. By using index decomposition analysis, we explore the factors contributing to the carbon dioxide (CO2) emissions in Chinese megalopolises from 1985 to 2010. An additional decomposition analysis of the industry sector is performed because of its dominant contribution to the total emissions. The booming economy and expanding urban areas are the major drivers to the increasing CO2 emissions in Chinese megalopolises over the examined period. The significant improvement in energy intensity is the primary factor for reducing CO2 emissions, the declining trend of which, however, has been suspended or reversed since 2000. The decoupling effect of the adjustments in the economic structure only occurred in three megalopolises, namely, the Yangtze River Delta (YRD), the Beijing-Tianjin-Heibei Megalopolis (BTJ), and the Pearl River Delta (PRD). In comparison, the impacts of urban density and carbon intensity are relatively marginal. The further disaggregated decomposition analysis in the industry sector shows that energy intensity improvements were widely achieved in 36 sub-industries in the PRD. The results also indicate the concentrations of energy-intensive industries in the PRD, posing a major challenge to local governments for a low-carbon economy. As economic growth and urbanization continue, reductions in energy intensity and clean energy therefore warrant much more policy attentions due to their crucial roles in reducing carbon emissions and satisfying the energy demand.  相似文献   

7.
This article studies the price relationships between EU emissions allowances (EUAs) – valid under the EU Emissions Trading Scheme (EU ETS) – and secondary Certified Emissions Reductions (sCERs)—established from primary CERs generated through the Kyoto Protocol's Clean Development Mechanism (CDM). Given the price differences between EUAs and sCERs, financial and industrial operators may benefit from arbitrage strategies by buying sCERs and selling EUAs (i.e. selling the EUA–sCER spread) to cover their compliance position as industrial operators are allowed to use sCERs towards compliance with their emissions cap within the European system up to 13.4%. Our central results show that the spread is mainly driven by EUA prices and market microstructure variables and less importantly, as we would expect, by emissions-related fundamental drivers. This might be justified by the fact that the EU ETS remains the greatest source of CER demand to date.  相似文献   

8.
Given recent developments on energy markets and skyrocketing oil prices, we argue for an urgent need to study the potential effects of world oil production reaching a maximum (Peak Oil) in order to facilitate the development of adaptation policies. We consider input–output (IO) modelling as a powerful tool for this purpose. However, the standard Leontief type model implicitly assumes that all necessary inputs to satisfy a given demand can and will be supplied. This is problematic if the availability of certain key inputs becomes restricted and it is therefore only of limited usefulness for the study of the phenomenon of Peak Oil. Hence this paper firstly reviews two alternative modelling tools within the IO framework: supply-driven and mixed models. The former has been severely criticised for its problematic assumption of perfect factor substitution and perfect elasticity of demand as revealed by Oosterhaven [Oosterhaven J. On the plausibility of the supply-driven IO model. J Reg Sci 1988; 28:203–17. [1]]. The supply-constrained model on the other hand proved well suited to analyse the quantity dimension of Peak Oil and is therefore applied empirically in the second part of the paper, using data for the UK, Japanese and Chilean economy. Results show how differences in net-oil exporting and net-oil importing countries are clearly visible in terms of final demand. Industries, most affected in all countries, include transportation, electricity production and financial and trade services.  相似文献   

9.
Water is required for energy supply, and energy is required for water supply, creating problems as demand for both resources grows. We analyze this “water–energy nexus” as it affects long-run electricity planning in the western United States. We develop four scenarios assuming: no new constraints; limits on carbon emissions; limits on water use; and combined carbon and water limits.We evaluate these scenarios through 2100 under a range of carbon and water prices. The carbon-reducing scenarios become cost-effective at carbon prices of about $50–$70 per ton of CO2, moderately high but plausible within the century. In contrast, the water-conserving scenarios are not cost-effective until water prices reach thousands of dollars per acre-foot, well beyond foreseeable levels. This is due in part to the modest available water savings: our most and least water-intensive scenarios differ by less than 1% of the region's water consumption.Under our assumptions, Western electricity generation could be reshaped by the cost of carbon emissions, but not by the cost of water, over the course of this century. Both climate change and water scarcity are of critical importance, but only in the former is electricity generation central to the problem and its solutions.  相似文献   

10.
In this article, an internal-reforming solid oxide fuel cell–gas turbine (IRSOFC–GT) hybrid system is modeled and analyzed from thermal (energy and exergy), economic, and environmental points of view. The model is validated using available data in the literature. Utilizing the genetic algorithm optimization technique, multi-objective optimization of modeled system is carried out and the optimal values of system design parameters are obtained. In the multi-objective optimization procedure, the exergy efficiency and the total cost rate of the system (including the capital and maintenance costs, operational cost (fuel cost), and social cost of air pollution for CO, NOx, and CO2) are considered as objective functions. A sensitivity analysis is also performed in order to study the effect of variations of the fuel unit cost on the Pareto optimal solutions and their corresponding design parameters. The optimization results indicate that the final optimum design chosen from the Pareto front results in exergy efficiency of 65.60% while it leads to total cost of 3.28 million US$ year−1. It is also demonstrated that the payback time of the chosen design is 6.14 years.  相似文献   

11.
Theory and empirics suggest that by curbing competition, incumbent electricity companies which used to be, and here are referred to as, Vertically Integrated Utilities (VIUs), can increase their profitability through combined ownership of generation and transmission and/or distribution networks. Because curbing competition is generally believed to be welfare-reducing, EU law requires unbundling (separation) of the VIU networks. However, the EU allows its member states the choice between incomplete (legal) and complete (ownership) unbundling. There is tantalizing anecdotal evidence that VIUs have tried to influence this choice through questionable means of persuasion. Such means of persuasion should be more readily available in countries with a more corrupted political culture. This paper shows that among the old EU member states, countries which are perceived as more corrupt are indeed more likely to apply weaker forms of unbundling. Somewhat surprisingly, we do not obtain a similar finding for the EU member states that acceded in 2004. We provide a conjecture for this observation.  相似文献   

12.
In this paper, we evaluate the Swedish Programme for improving energy efficiency in energy-intensive industries (PFE). Since 2005, some 100 energy-intensive companies have entered this 5-year voluntary agreement (VA) and been exempted from the EU minimum tax on electricity. In return, each company is required to: conduct an energy audit and analysis; identify and invest in profitable electricity saving measures; implement and certify an energy management system; introduce routines for energy efficient procurement and project planning. For most participants the first programme period was completed in 2009 and available data enables this PFE ex-post evaluation. An impact evaluation compiles and analyse data that the companies have reported to the administrating agency, the Swedish Energy Agency (SEA). This assessment of quantifiable results is complemented by a process-oriented approach that combines studies of policy documents, previous evaluations and personal communication with administrators as well as companies. The bottom-up calculation method distinguishes between gross and net impact. While the SEA estimates a gross impact of 1,450 GW h/year, the net impact consists of an interval between 689 and 1,015 GW h of net annual electricity savings. PFE has effectively and, to a low cost, exceeded the estimated impact of a minimum tax and can thus be judged as successful. A comprehensive evaluation plan could facilitate relevant data gathering in PFE and similar VAs and could, in doing so, improve accuracy and possibly reduce evaluation cost. Such a plan should give weight also to the organisational changes, with potential long-lasting effects, that these programmes are capable of promoting.  相似文献   

13.
The paper gives a bibliographical review of finite element methods (FEMs) applied for the analysis of pressure vessel structures/components and piping from the theoretical as well as practical points of view. This bibliography is an addendum to the Finite elements in the analysis of pressure vessels and piping—a bibliography (1976–1996) published [Int J Press Vess Piping 69 (1996) 279] and Finite elements in the analysis of pressure vessels and piping, an addendum (1996–1998) published [Int J Press Vess Piping 76 (1999) 461]. The new bibliography at the end of the paper contains approximately 670 references to papers and conference proceedings on the subject that were published in 1998–2001. These are classified in the following categories: linear and nonlinear, static and dynamic, stress and deflection analyses; stability problems; thermal problems; fracture mechanics problems; contact problems; fluid–structure interaction problems; manufacturing of pipes and tubes; welded pipes and pressure vessel components; development of special finite elements for pressure vessels and pipes; finite element software; and other topics.  相似文献   

14.
This study not only establishes that the institutional changes (the change of political regime) and economic changes (the energy crisis) that occurred during the 70s and 80s had an important effect on business strategies within the Spanish electricity sector, but, above all, it shows how the resulting regulatory model was not the product of any clearly defined plan on the part of the Spanish authorities (as the majority of authors seem to implicitly or explicitly maintain), but rather it arose from the dialectical interaction between companies which resisted losing the power of the market, and institutions which, in order to define any medium term energy policy in the future European domestic electricity market, required an increase in their regulatory power.  相似文献   

15.
The present study is aimed at predicting liver tumor temperature during a high-intensity focused ultrasound (HIFU) thermal ablation using the proposed acoustics–thermal–fluid coupling model. The linear Westervelt equation is adopted for modeling the incident finite-amplitude wave propagation. The nonlinear hemodynamic equations are also taken into account in the simulation domain that contains a hepatic tissue domain, where homogenization dominates perfusion, and a vascular domain, where blood convective cooling may be essential in determining the success of HIFU. Energy equation for thermal conduction involves two heat sinks to account for tissue perfusion and forced convection-induced cooling. The effect of acoustic streaming is also included in the development of the current HIFU simulation study. Convective cooling in large blood vessel and acoustic streaming were shown to change the temperature near blood vessel. It was shown that acoustic streaming effect can affect the blood flow distribution in hepatic arterial branches and leads to the mass flux redistribution.  相似文献   

16.
In this article, we analyze social preferences for a partial substitution programme of electricity generated by conventional energy sources, for energy generated from a local renewable energy source, such as forest biomass. This analysis sets arguments in favour of accelerating the introduction of this renewable technology in the Spanish Electricity System. Simultaneously, two methodological goals concerning the contingent valuation method are discussed. In the first one, we analyze if there are statistical differences in the willingness to pay (WTP) when a single- or a double-bounded format is employed to ask the valuation question. Results show that WTP estimates from single- and double-bounded significantly differ. In the second one, we analyze the effect of the periodicity of the payment vehicle on the estimates of welfare change. The timeframe specification of the payment vehicle has been scarcely studied, and this fact constitutes the main contribution of this paper to the specialized literature. Results show that periodicity influences upon the probability to favour the proposed change. The periodicity does not affect to the mean WTP obtained in the single-bounded format, but there are statistical differences in the double-bounded format. These results might be explained by the presence of yea saying and payment scale bias.  相似文献   

17.
The dependence on foreign trade increased sharply in china, and therefore Chinese economy is obviously export-oriented. The Global Financial Crisis will impact the Chinese economic growth violently. Chinese government has recently adopted some effective measures to fight against the Global Financial Crisis. The most important measure is the 4 trillion Yuan ($586 billion) stimulus plan which was announced on November 9, 2008. This paper discusses the influence on energy consumption and economic growth of Global Financial Crisis and the stimulus plan against it by input–output analysis. The results show that the fall of exports caused by the Global Financial Crisis will lead to a decrease of 7.33% in GDP (Gross Domestic Production) and a reduction of 9.21% in energy consumption; the stimulus plan against the Global Financial Crisis will lead to an increase of 4.43% in economic growth and an increase of 1.83% in energy consumption; In the Global Financial Crisis, energy consumption per unit GDP will fall in China.  相似文献   

18.
The aim of this paper is to analyse cross-country differences for shares of renewable electricity in the EU-27 for the period 1996–2005. We carry out a standard convergence analysis and then examine the evolution of the entire distribution, namely the external shape, intra-distributional dynamics and ergodic distribution. Our main results are as follows. First, there has been a clear convergence pattern for renewable electricity shares across countries. Second, the shape of the distribution has varied significantly over time, with more countries positioned around the mean in 2005 than in 1996. Third, the analysis shows that intra-distributional mobility has been relatively high, especially in those countries with the highest share in the initial year of our sample. Fourth, in spite of this, large cross-country differences will likely persist for RES-E shares in the hypothetical long-term equilibrium, which implies that a major impulse to national RES-E support policies will be necessary in the coming years to shorten this gap.  相似文献   

19.
The article gives a bibliographical review of the finite element methods (FEMs) applied for the analysis of pressure vessel structures/components and piping from the theoretical as well as practical points of view. This bibliography is an addendum to the Finite elements in the analysis of pressure vessels and piping-a bibliography (1976–1996) published in the Int. J. Press. Ves. Piping 1996;69:279–339. The added bibliography at the end of the article contains approx. 630 references to papers and conference proceedings on the subject that were published in 1996–1998. These are classified in the following categories: linear and non-linear, static and dynamic, stress and deflection analyses; stability problems; thermal problems; fracture mechanics problems; contact problems; fluid–structure interaction problems; manufacturing of pipes and tubes; welded pipes and pressure vessel components; development of special finite elements for pressure vessels and pipes; finite element software; and other topics.  相似文献   

20.
We analyze pay-as-you-go (PAYG) contracts subscribed by 10,120 consumers living in Benin (Sub-Saharan Africa) to purchase solar kits or panels for lighting and charging services. PAYG are flexible loans that allow fees payment through mobile banking. Most of the PAYG consumers live in well electrified areas (Cotonou, Porto Novo, Abomey Calavi, in the coastal zone). By estimating a very simple multinomial logit model, we find that these customers have a high probability to enroll in PAYG contracts. Living in urban and peri-urban areas, they use solar devices to substitute expensive and often unreliable grid electricity services. Consumers located in more periferic and less electrified areas (Savalou) have a low probability to default, as the substitution effect is weaker. Overall, in our case study, PAYG targets credit worthy consumers, in order to decrease the investment risk of the company providing solar devices. These results cast some doubts as to whether PAYG bridges the “last mile” electrification gap.  相似文献   

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