نشریه انرژی ایران
سال سیزدهم شماره 3 (پیاپی 48، پاییز 1389)

The objective of this paper is to examine the performance of solar systems in buildings. This subject waschosen, because there are not sustainable buildings in Iran. In this paper, the main question is that How designed buildings are responsive to thermal requirement and if these buildings can be designed by relying on regional climate conditions, what the impact would be on energy consumption reduction.For responding to thisquestion, design was accomplished in two stages. At first, thermalload wascalculated for this design without solar systems Then, the solar system was added to the project and its impact on improving the thermal conditions was calculated. The results show, using a solar system can reduce the amount of required heating about 65%.

Energy is one of the important inputs that affects economic growth in different countries. There are many energy resources in Iran and energy which is utilizedas supply factor in different production processes. Therefore direct and indirect effects of energy consumption on economic growth can help policy makers to adopt right policies. In this paper,tosurvey the energy consumption effects on economic growth The years between 1359 to 1368, when the country was involved in imposed war, and the afterward years (between 1369 to 1378) were taken into consideration the results show that that there is positive relation between energy consumption and economic growth even during imposed war period.

In order to remove the latent load, the traditional refrigerant vapor compression system (VCS), the process air is cooleddown below its dew point in order to condense out water vapor contained therein. The dehumidified air is then reheated to meet the required indoor temperature conditions. This way two loads will be added to the system. which are, (1) the energy required to bring the air from the supply temperature down to the temperature of condensation of water vapor contained in the process air (below the dew point of the air), and (2) the energy needed to reheat the air from that temperature up to the supply air temperature. The desiccant cooling can be either a perfective supplement to the traditional vapor compression air conditioning technology to attenuate the effects of its drawbacks, or an alternative to it for assuring more accessible, economical, and cleaner air conditioning. Technical and economic optimization of a hybrid-liquid desiccant cooling system is investigated in this paper. In such a system air passes through the liquid desiccant dehumidifier in the first stage and over evaporator of a vapor compression cooling system in the next stage. The liquid desiccant was recovered by using both heat rate provided by the condenser of vapor compression cooling system as well as natural gas energy. The system COP and the total annual cost (investment and operating costs) were chosen as two objective functions. The optimization was performed by using multi-objective Genetic algorithm technique. The results of modeling and optimization for our case studies (Ahvaz and Bandarabbas) with 12 hours system running per day and 6 months per year for 15 years showed that the costs of Hybrid-Descicant cooling system in Ahvaz and Bandarabbas are about 10% and 24% cheaper in comparison with vapor compression cooling system, respectively. Also, Power consumption rate is reduced 0.575 (Kw) and 0.664 (Kw) per refrigeration Ton for Ahvaz and Bandarabbas, respectively in comparison with the application of vapor compression cooling system.

Efficiency and energy outputof gas turbine decrease while temperature and humidity increase, the maximum loss is insummer which results in a lot of problems. To compensate this loss, cooling of compressor inlet air is used. Dependingonthe place and condition of thesite, different methods are used to achieve this target that briefly consist of vaporizing method, chilling method and storage method. Simulation of gas turbine items is necessary to predict the operation of gas turbine off-design condition. In this research, a single shaftgas turbine in condition of off-design is used and the effects of different methods of cooling have been studied. results of modeling of Solar Centaur T4500 in Ahwaz (the average of maximum temperature of 48.2 C and relative humidity of13%) exhibits 28% decreace in energy output. According to the results,whenrelative humidity increases, performance of vaporizing method decreases, then in warm and wet places, using chilling methods are recommended.

Electricityhas been recognizedasone of themost pervasivepublicservices, Therefore,anypoliciesincludingremoving subsidies will economic and socialconsequencesindifferent partsofthe country, includingelectricity industry.Therefore, managers of electricityindustry,are interested in studying the consequences of this policy from people's points of view. One wayto obtainfeedbackwithinthesocial and economic issues,is doing surveysurveys. This paper wasimplementedin1389, with the aim of studying subscribersattitudetoward theeconomic and socialconsequences of removing subsidies ofelectricity in Tehranprovince onasample of 1000 person s that werechosen with therandomsamplingmethod. Researchtools formed with agaugeattitudes questionnaire with 90 items and six categories based on Likert scalefrom 0 to3degrees and commonstatisticalmethodswere usedfordata analysis.

In this study some scenarios are designed and analyzed in order to future studyon Iran power plant development for meeting long term electricity demand. The aim of this study is analyzing effects of Iran electricity generation policies on shares of different power plants. Iran energy resources for power generation can be divided into three general categories: fossil, nuclear and renewable resources, therefore three scenarios based on each resource are designed and studied. For this purpose, current situation of electricity demand and supply in Iran are studied and possible paths for future power generation and possible answers to the question: “When, how much and which power plant should be built to support future demand?” are discussed. Hence using LEAP software, three scenarios are designed to supply 20 years demand and are presented in 5 year programs. Result shows that based onfossil scenario (business as usual), share of fossil recourses will ach to 82 percent of total resources until 2030. But based on thesecond scenario with development of utilization of nuclear energy, share of fossil recourses will be 67 percent and by emphasizing on renewable energies at the third scenario this share will be 70 percent.

The first step to achieve wind potential is the selection of suitable sites in the country with appropriate wind power density. The best available option to carry out such a study for a particular location, is the wind data recorded by the nearest synoptic metrological office. For this study, the wind velocity period recorded by Amir Abad Synoptic Metrological Office has been used since it shows a faster wind velocity amongst the fifteen metrological stations located in Mazandaran Province (except for Baladeh region). The k and c (weibull parameter) were computed for a period of 58 months from March 2005 to December 2009 from which the density of wind strength was obtained. The total average k and c in this station at theheight of 50 meters werecalculated to be 1.23 and 4.01 m/s. using these figures, the average wind density coefficient at theheight of 50 meters was calculated 97.97 Watts/m2 indicating a Weak Potential wind category. The maximum density at 142.10 Watts/ m2 was attributed to to the month of July and the minimum at approx. 62 Watts/ m2 was attributedto the month of October.