نشریه انرژی ایران
سال نوزدهم شماره 3 (پیاپی 72، پاییز 1395)

This study was curred out to evaluate the irrigated wheat energy function production and determination of the role of each agricultural input such as water energy in plain Mahiar shahreza region. For this purpose, all inputs used and outputs production, were recored through the collection of field data of 70 randomly selected farmers fields in Mahiar. Then, the equivalent energy of the all inputs and outputs were calculated and the coefficients of Cobb-Douglas and Transcendental equation energy were culculated by regression analysis and the least squares method in the software EViews 5. Energy output can be estimated by inserting the energy inputs in these two equations. Statistical comparisons indicated that the transcendental equation with respect to the energy equation Cobb- Douglas production function with better fit data in energy wheat production. Based on inputs elasticity, the most effective inputs in wheat grain energy were: cultivated area, fertilizer, machinery and consumed water respectively. Water elasticity with -0.05 indicated that water was consumed excessively.

This study investigates the relationship between energy consumption and economic growth by using Iranian annual time series from 1973-2012. The non-causality approach of Toda and Yamamoto (1995) to causality testing and the bounds testing approach to cointegration, are proposed. In this study, energy consumption is further disaggregated into oil, gas and electricity consumption in order to present more robust analysis. The findings from this study, reveal a unidirectional causal relationship between total energy consumption and economic growth running from total energy consumption to economic growth. This is also true in the case of oil consumption and economic growth with the direction of causality running from economic growth. There is a bidirectional causal relationship between gas consumption and economic growth. The study also shows the there is a unidirectional causal relationship between electricity consumption and economic growth running from electricity consumption to economic growth. The cointegration test identifies long run relationships between total energy consumption and economic growth and also between gas consumption and economic growth. Meanwhile, the cointegration analysis reveals no long run relationship between oil consumption and economic growth and also between electricity consumption and economic growth.

The road transportation sector has been the greatest consumer of gasoline in the country. Continuously growing demand of the sector has caused serious challenges the most important of which has been the gasoline supply problem. The deficit caused by difference between import price and sales price of gasoline has always put pressure on the government’s budget. As the first step, to solve this problem, gasoline consumption was supplied by quota since July 2007 using smart cards. Unlike most studies which studied this policy from an economical point of view, using data mining techniques, this paper has a new approach. Two-step clustering is used for this purpose. Data are gathered from 2005 to 2010 for the city of Tehran. Since the period contains years before and after gasoline quota, the study results seem satisfactory to conclude about the gasoline quota effects. The results show that the policy had a short-term impact on the reduction of gasoline. Moreover taxi trips was a short term solution and that expansion of Metro lines is a long term solution to solve the road transportation sector dilemma.

In this study, the optimal design of a hybrid system including solar collectors and Geothermal pumps to provide heating load of a building with technical and economic point of view hase been investigated. The performance of the various components of the system has been adjusted so that in addition to preheating the evaporator inlet fluid and setting this temperature to the ideal, coefficient of performance of heat pumps has also increased. First, optimal system has been evaluated technically and economically and optimal design with technical and economic considerations have been selected. selected model has 3.9 average performance factor for heat pumps, 30.375 square meters for collector area and 472.5 meters for pipes length (5 wells with 47.5 feet and the U-shaped tubes series were used). system Overall costs have been calculated, US $ 85,680 by minimizing the economic costs as the objective function and transferring the operational costs to the base year.

The impact of ICT on energy consumption is one of the most important and multifaceted topics. Expansion the ICT can reduce energy consumption by increasing efficiency while the emergence of new products and services in this regard will lead to additional demand for energy. Accordingly this study examined the non-linear effect of ICT on energy consumption in Iran over the period 1974-2012. For this purpose, used the energy consumption per capita and the ratio of ICT capital stock in the communications sector to GDP (as an indicator ICT) variables in the form of a smooth transition regression (STR) regime change as one of the outstanding models. The estimated STR model supports a nonlinear threshold behavior in the relationship between ICT index and energy consumption per capita in in a two regime structures with a threshold level of about 9.62 percent. So that ICT index in the first regime had positive impact energy consumption per capita, while in the second regime this effect is negative. . So we can expect that by increasing the capital stock of ICT in the communications sector to GDP ratio than threshold level, seen a decline in energy consumption per capita in the country.

The impact of oil price volatility on the financial markets in Iran Review: The purpose of this study was to evaluate the effect of oil price uncertainty on the financial markets (exchange rates, coin price index and stock prices) using time series data for the period 1384 to 1392. For the modeling of the effects of oil price uncertainty on stock indices, exchange rates and gold prices ARCH and GARCH models to test the effects of oil price uncertainty on the markets, their methods of vector regression (VAR) is used. The estimated results indicate a negative correlation between oil prices and instability in financial markets. The results of analysis of variance showed that the greatest impact on stock index of the exchange rate, uncertainty of oil prices and the inflation and the price of gold. Therefore, we conclude that in the next period will be most affected by the exchange rate on stock indices, stock price index, inflation and the price of gold coins.

Environmental issues, especially climate change, due to increased greenhouse gas emissions in recent decades, have become a global issue. Power generation sector has 30.2% share of CO2 emission that it's the biggest environmental pollutants in Iran. Scenario analysis method based on the Long-range Energy Alternatives Planning system (LEAP) model was used for an analysis of reduction of greenhouse gas emissions in the electricity sector of Iran. Business As Usual (BAU), increasing the efficiency of power generation, nuclear and renewable energy and combine efficiency and renewable energy and nuclear scenarios represent different development paths which are possible in Iran’s electricity sector due to various policies. The simulations are applied until the year 1420, while 1390 is set as the base year. In the Business As Usual Scenario, greenhouse gas emissions grew by 5.8% annually between 2006 and 2030, while electricity output grew at an average of 6.6% per annum in this period. In the other three scenarios, greenhouse gas emissions control policies are considered. Thus, the greenhouse gas emission reduction between the BAU and increasing the efficiency of power generation, nuclear and renewable energy scenarios, and combination scenario is 198438, 228877, 360898 thousand CO2eq tons.

In recent decades, greenhouse gas (GHG) emissions, particularly CO2, has led to catastrophic environmental impacts such as global warming. In addition to natural emissions, human activities are among the most important causes of CO2 emission. Meanwhile, energy consumption possesses the biggest share in CO2 emission. Various sectors, including industry, transportation and building, consume energy which each one has a significant role in air pollution and GHG emissions. According to official statistics, buildings own more than one third of the world energy consumption. Therefore, the role of huge buildings, as big energy systems would be very important. In this paper, a model for CO2 emission caused by energy consumption in a large building is provided and the emitted CO2 from a real building as a case study is then calculated.

Nowadays, due to significant increase in demands of electric motors for residential, commercial and industrial applications, and for optimum consumption of electrical energy, the design and manufacturing of high efficiency motors and related variable speed drives have been regarded by many suppliers. Among several kinds of motors, the brushless DC (BLDC) motor is employed in many applications due to its high efficiency, high power and torque density, and ease in control, simple fabrication, high reliability, and lower maintenance. This motor is similar to PMSM in construction, while is controlled as easy as of DC motor. This paper to help for development and employing BLDC motors, reviews the different aspects of BLDC motors including performance, modeling, employed inverters, assessment of control methods for BLDC motor and implementation of its drive. Advantages and disadvantages of different control methods, remarks on various position sensorless methods, the effectiveness of various minimization schemes for commutation torque ripple, and control of BLDC motor in constant power region or flux-weakening are described in more details. Finally, some practical points are suggested for manufacturing of a commercial BLDC motor drive.

Divisions of power system are affected by different parameters like natural disasters and unforeseen events. This case is important for improvement of present networks or design of new networks, and it can prepare the network for fast restoration with minimum damage. The objective of this study is to increase security of energy supply in sensitive points using renewable energy resources so that networks technical constraints is satisfied beside energy resources uncertainty and sensitive loads priorities. Due to the presence of DG units and the uncertainty of their power, common methods of security evaluation of energy supply are not applicable directly. Finally, a comprehensive algorithm based on imperialist competitive algorithm, scenario reduction, and optimal power flow is proposed and supply adequacy of consumers is evaluated by solving a set of optimal power flow equations. The proposed model is presented in MATLAB and GAMS environments and optimal mix of energy resources is obtained to increase reliability of network. Final results show the effectiveness of the proposed algorithm in optimal design of hybrid energy resources and remarkable improvement of energy supply security.

The main goal of the study is identification and ranking of Energy Efficiency Barriers on the base of Expert view in the armed forces of Iran. This study is a descriptive and survey research in 2014-2015 in one of the branches of the military in the armed forces of Iran. The Statistical population of the study was 105 personals of Energy Engineering and Management Department. We found the main barriers in Library studies (Managerial, Information, Financial and Cultural Barriers) and we used 2 questionnaires in survey part of the research. AHP method was used to rank barriers. Findings showed that the reluctance of senior management (Important Coefficient: 0.3055) the lack of funding for improvement projects (Important Coefficient: 0.2019) are the most important barriers and the high cost of Identification opportunities for improvement (Important Coefficient: 0.2019) has the lowest Important Coefficient. The armed forces can make a suitable infrastructure for implementation of energy policies by Careful planning of officers to modify consumption patterns To optimize allocation of credit and fund for investment projects Cultural actions and Legal regulations to raise the sense of responsibility of staff.