نشریه انرژی ایران
سال هفدهم شماره 2 (پیاپی 63، تابستان 1393)

In this study a reciprocating engine- driven CHP system is assumed to meet part of the electricity and heating (space heating, domestic hot water) demands of a 3 flat building in various climates of Iran. First the optimum engine capacity and the auxiliary boiler capacity have been estimated by evaluating the electricity and heating loads of the building for each typical climate. Depending on the costs of the system, the financial viability of the project has been evaluated in the terms of financial indicators, such as payback time, IRR, NPV, and the cumulative cash flows for different cases plotted over the project life. In the main scenario it was assumed that the exported rate of electricity would be equal to the rate of delivered electricity by the utility and it was set according to the electricity consumption based on the Law of Targeted Subsidies Plan, also GHG reduction credit of 30 $ was assigned per equivalent ton of CO2. To make comparison possible, different rates for electricity and natural gas were considered; also different credits per ton of CO2 reduction were assigned. Calculations show the remarkable effect of exported rate of electricity on reducing payback time of the project. The results indicate that government financial support and promotion schemes are usually required, and regional policies clearly helps promote CHP system adoption.

Using natural daylight in buildings is one of solar energy applications in architectural and building industry. In this review article various aspects of application of daylight in buildings is discussed. At first the advantages of using natural daylight instead of artificial lighting is described. Then various methods of light transfer to the internal places of the building and advantages disadvantages of each method is discussed.

Exports of crude oil always have complexities in sale way, pricing method and the type of the contrant at oil exporter countries. This strategic product is influenced by national politics, international relations and events that happen in the world addition to economic factors such as supply and demand. Iran's oil revenues is nearly 20 percent of gross domestic product (GDP), about 80 percent of total exports and 60 to 70 percent of the state budget. Thus, the amount of oil exports is an important factor to Iran’s economy and the mechanism of petroleum export, is very considerable importance. As the years of sanctions and reduced oil exports, has increased the importance of this issue. In this paper, we try to find the optimal method of crude exports by hierarchical analysis conducted on Iran 's crude oil exports. The decision on this issue is related to both energy and financial areas therfore, Two expert opinions in these fields have been received. The calculations have been performed with the help of the software Super decisions. Analysis of the results shows that there is conceptual approach difference between economic and energy experts.

Nowadays, Microgrid systems can be applied as a tool for power production base better quality, higher efficiency and reliability. Compensating the effects resulted of from the randomness and variableness of access to initial generation by non-dispatchable sources is a fundamental and critical challenge. In this paper, a general formula for estimating optimum operation strategy to minimize the cost related to generation sources and responsive load as well as reducing market clearing price (MCP) combined with demand response has been presented in order to regulate mismatch power. In the suggested Optimization problem, A new approach namely multidimension imperialist competition algorithm has been applied for minimizing the system cost function. This approach also satisfies fulfilling the constraints for the complete feeding of load demand and the technical specifications related to each of the resources presented in the MG under study. Furthermore, a comparison between the suggested algorithm and the modified conventional energy management system (MCEMS) algorithm has been performed experimentally by testing over institute de recerca en energia de catalunia's MG. The obtained results demonstrate the efficiency of the proposed algorithm for fulfilling load demand, reduction of the total generation cost (about 31%) and reduction of MCP compared to the MCEM algorithm.

There is a great interest to plan and manage energy systems in order to minimize generation cost and electricity prices, and also to optimize operation of renewable energy sources in advanced power grids and energy management systems. Since, demand side management increases consumers’ participation in power systems, their characteristics modelling has a crucial significance in power systems. In this paper, to have an economic dispatching of generation in microgrids, a multidimensional artificial bee colony optimization algorithm is implemented. Accordingly, considering bids of each generation and storage source and also the offered price of interruptible loads, optimum energy management is achieved. Finally, a comparison between the results of proposed algorithm and Modified Conventional Energy Management Systems shows an approximate 30% of cost reduction, higher speed of central controller’s decision making, and improvment in the performance of the existing sources in studied microgrid power system.

In this paper، the energy consumption structure of the Iran''s agriculture sector has been analyzed and modeled by using an integrated analytical methodology. According to ISIC (International Standard for Industry Classification)، agriculture sector (as well as its related energy consumption) has been classified into 10 main sub-sectors as following: farming and horticulture، water pumping، poultry breeding، animal husbandry، floriculture، greenhouse farming، mushroom farming، fishery and aquaculture، forestry and rangeland، and others. As the sub-sectors are not similar، and the formulations and analysis of the energy consumption structures are different، an analytical approach was used in order for alignment and developing the energy demand model. Considering features and flexibility of LEAP software، the modeling was done by using this software. The results show that the total energy demand of this sector، which was 45 MBOE in 2010، will change to an amount between 44 and 61 MBOE. The average energy demand growth rate of the agriculture sector in reference، high economic growth rate، low economic growth rate، energy policy-making with the reference economic growth rate، energy policy-making with low economic growth rate and energy policy-making with high economic growth rate scenarios were annually 0. 65%، 0. 56%، 0. 83%، -0. 19%، -0. 22% and -0. 09%، respectively.

Due to the high potential of solar energy in large areas of the country, employing the divine gift in the industry, an important step toward energy independence and reduce the country's 20-year outlook for fossil fuel industries will be. This paper discusses the feasibility of using the photovoltaic industry to supply electricity to BTS deals. Telecom companies need to increase the coverage of mobile BTS installation and power supply in several areas BTS, the power grid in remote areas of the difficulties facing the development of a telecommunication network. In this paper, first introduced ways of powering the BTS requirement, the climate and weather of a particular region considered based on the requirements of the photovoltaic system is designed disposable BTS. Furthermore, the system is designed in several different scenarios simulated by HOMER software and economically with other energy supplies such as diesel the national grid were compared.

Review of economic developments in Iran over the past four decades has shown that oil revenues, has had deep and wide impact on economic indicators. The Two channels which oil price changes directly or indirectly affect inflation _as the most important Economic variables_ are: increase in demand (Mainly by government public budget and Influencing the components of monetary base and money supply) and increase in production costs (via the price of factors of production). In this regard, the present paper attempts to investigate the nature and causes of oil price pass-through into inflation in the short-and-long term; analysis of the pass-through and in addition design the necessary policies to control its destructive consequences. For this purpose, the dynamic error correction model was used and the data were collected monthly from 1380/1 to 1390/1. The findings showed that the oil price pass-through into inflation in both short-and-long term were Positive and incomplete. Therefore, it would be useful in policymaking.