نشریه انرژی ایران
سال بیستم شماره 1 (پیاپی 74، بهار 1396)

Lack of national budgets, high capital cost of infrastructure projects in power transmission grid and associated risks are among serious complications for transmission system expansion. A fundamental solution to overcoming these difficulties is attracting private sector capital to finance these projects. However private sector participation requires a certain level of profitability and risk management. In this paper a framework for attracting merchant investment to finance power projects has been proposed which can be adapted in other energy infrastructure systems. In the proposed algorithm, maximizing merchant investment is formulated as an objective function in the process of transmission expansion planning problem .The objective functions and constraints such as minimizing the construction cost of transmission lines, minimizing congestion costs, maximizing absorbed private investment and investment risks are used for problem modeling. The scenario analysis is used for modeling uncertainties; the NSGA II algorithm is used to obtain pareto-optimal solutions and the fuzzy satisfying method is used to choose the best solution. Final results are shown on the IEEE 24Bus reliability test system. With the proposed method the system planner can be assured about maximized merchant investment and also the profitability and risk hedging could be guaranteed for private sector investors.

In this paper, the effect of operating conditions on the cathode of a fuel cell is made of plastic on its performance. For this purpose, two-dimensional and two-phase simulation of a fuel cell unit including gas ducts, gas diffusion layers and the cathode and the anode catalyst and the membrane area was conducted. The governing equations of the fuel cell using multi-phase model caraway and with regard to the single zone model was solved using coding and concentration VaknshGr components resulting in cell polarization curves were obtained. The effect of voltage, pressure, temperature, speed and relative humidity of the cathode on the concentration of oxygen and water as well as cell function studied and evaluated. The results show that by increasing the operating temperature of the cell, fuel cell performance improves. With increasing speed, pressure and relative humidity of the gas stream entering the channel, fuel cell efficiency increases. In order to validate the results obtained, the yield curve of single-phase and two-phase simulation compared with experimental results and good agreement was observed between them.

Demand Response (DR) is counted as one of the main important components in the smart grids. It means the participation of customers in modifying their consumption patterns at the peak hours in order to reduce costs and improve the network reliability. First, in this paper, different types of the incentive based and price based demand response programs (DRPs) and their subsets are investigated. Then, they are modeled and implemented on the Kermanshah province’s load curve on 22 July 2015. Also, their effects on the price reduction and improving the load curve characteristics and network reliability are presented. Finally, a procedure in order to prioritize DRPs based on the electricity company’s different policies is proposed.

As regards carbon dioxide emissions are the major cause of climate change for numerous, study on the factors affecting its emissions have a high significance. This study focuses on the relationship between co2 emissions and GDP, population growth, openness and energy consumption, which inclusive a wider range of factors affecting on co2 emissions will be examined. For this purpose, long-term and short-term relationship between co2 emissions and other variables is estimated and analyzed with utilizing ARDL model for annual data from 1972 to 2011.The results of this study indicate that all variables except for openness, have a positive impact on co2 emissions, while openness has a negative effect on co2 emissions.

In the present study, the effect of occupants’ clothing on the themal comfort and energy consumption in a theater hall with underfloor air distribution system has been analyzed. For this issue, openings are placed in three different places (unser seats, in front of seats and on the walls around the hall) and two different thermal resistance have been considerd for the clothing (0.8clo and 1clo). Computational fluid dynamics (CFD) methods has been used to predict the effect of occupants’ clothing on thermal comfort conditions and energy consumption in this space. Based on the results, for the same thermal comfort conditions, when the clothings’ thermal resistance increase, the temperature of an inlet air decreases and temperature distribution becomes invariable. Aslo, these conditions lead to decrese mean temperature and air velocity in the occupied zone. Also when the clothings’ thermal resistance increase the energy consumptione is decreased. On the other hand, the results show that energy consumption is respectively decreased about 9%, 7% and 6% for the openings under the seats, infront of seats and on the walls.

The increasing of population, energy demand and environmental pollution due to using fossil fuels, have guided the societies to utilize renewable energies. In this case, the solar chimney power plant is one of the most applied means for energy exploitation. Due to its low efficiency, optimization is a way for enhancing the system performance. In this study, optimization of solar chimney was carried out for the purpose of reaching the highest theoretical power. The objective function is the power output of the system and the solution is based on the optimum construction cost of a 200 MW power plant. The design variables cover the geometric parts including chimney height, chimney radius, collector height, collector radius and the turbine distance from the ground. Also, the mathematical model was validated with the experimental data of the Manzanares solar chimney in Spain. For writing the optimization algorithm, the SQP (Sequential Quadratic Programming) algorithm and the evolutionary algorithm were utilized. Finally the optimum amounts for reaching the maximum power output were obtained.

Electricity has a determinant role in national security and social and political stability as one of important sub- structures; as systems and inside urban convenience and even outside urban is depended on extension of electricity market and structural reform presses in whole of the world. Iran is also passing from natural monopoly structure toward competition markets and new structure that productises will compete for selling energy. In this paper is surveyed household electricity consumption’s demand function along by surveying of accomplished pricing structural variation in during of 1355-1370 and 1371-1389. Because of that, we use of purports of Engel-Granger cointegration test and Durbin- Watson cointegration test. Results show that consumers are inelastic toward oil price variations in both of periods. Even in second period, consumptions’ dependence increased on electricity energy. In addition, electricity demand is increased additively by population increasing.

Energy intensity index represents the amount of energy consumed by each of the energy carriers per unit (production or added value). Considering the role and significance of this index in the economies of the countries, this research covers factors affecting energy intensity in the OECD countries during 2001-2014 using data panel econometrics and generalizes method of moments. During the years under study in this research, energy intensity of the previous period, GDP, foreign currency rate, HDI and Internet Users of the countries have been of the utmost significant factors affecting the energy intensity of the OECD countries. Meanwhile the energy price, as a factor, has had impact on the energy demand and consequently energy intensity. The results indicate that there is a meaningful and negative correlation between energy intensity and energy price, GDP, foreign currency rate and internet users while there is a meaningful and positive correlation between energy intensity and HDI and energy intensity of the previous period.

Nowadays , energy as vital institutions in developing countries regarded economic activity .The oil shocks of the past decades has led to a new term called " energy intensity" is raised in energy economics literature . Hence in the present study was to examine the relationship between the energy intensity and the rate of industrialization in major exporting countries between the two groups and the import of crude oil for the period 2013-1990 using data Panel is presented. The results show that the oil-exporting countries , mainly in developing countries classified relation between energy intensity and the industrial structure of the countries there , While crude oil importing countries that are classified in the group of developed countries increased by 10 % Industrial Index ( capital employed ) , energy intensity by 6.0 percent increase.

The amount of radiation from the atmosphere to the surface as the main input on the use of solar power in the design and modeling of the relevant equipment. As well as other phenomena in nature, such as the intensity of solar radiation on the surface evaporates, flooding, rain, environmental pollution and also has a direct effect. Because of this, many models have been developed to measure a parameter that varies proportional to the geography and climate of each region with each other. In this study, using data between 1957 and 2005 in the city of Bam measured in Kerman province, the amount of solar radiation received by Earth-based models such as AngstroÈm and Paige were calibrated. It was extended to Bam relations and curve light intensity for each of the actual radiation that have been extracted from the Meteorological Organization of Iran, was drawn. Then the measured value of the model were compared with the computational model most consistent with the values recorded for the station in question, was selected as the optimal model for the Bam area. Evaluation of the relationship and estimate the error of each of them, with conventional tests and the use of quantities such as the average percentage error, mean baseline error, root mean square error, the standard error of the estimate and the correlation coefficient were used. Thus, all comparative figures in the tables are calculated on the basis of their classification and optimal model was chosen for the city of Bam. As a result of the proposed relations for the city of Bam, the possibility of modeling to estimate the intensity of the sun at any time of the year will be possible.