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Located in the south of Iran, Jiroft Paper Mill Company requires an integrated combined heat and power plant, which can provide 50 MW of electric power and 100 ton h-1 saturated steam at 13 bar, to produce paper from an adjacent eucalyptus forest. The plant is composed of an air compressor, combustion chamber, air preheater, turbine, as well as a heat recovery steam generator. The design parameters of the plant were chosen as: compressor pressure ratio (rc), compressor isentropic efficiency (ηAC), gas turbine isentropic efficiency (ηT), combustion chamber inlet temperature (T3), and turbine inlet temperature (T4). In order to optimally find the design parameters a thermoeconomic approach has been followed. An objective function representing the total cost of the plant in terms of dollar per second was defined as the sum of the operating cost related to the fuel consumption and the capital investment for equipment purchase and maintenance costs. Subsequently, different parts of the objective function have been expressed in terms of decision variables. Finally, the optimal values of decision variables were obtained by minimizing the objective function using sequential quadratic programming. The influence of changes in the demanded power and steam on the design parameters has also been studied for 40, 50, 60, and 70 MW of net power output, and 100, 120, and 150 ton h-1 of saturated steam mass flow rate. Finally, the sensitivity analysis of change in design parameters with change in fuel or investment cost was performed. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Summary: This paper proposes a novel structure to optimize the operational strategies of responsive farms for day‐ahead peak shaving. To achieve the aim, the modern irrigation system of farms, including groundwater, surface water, and booster water pumps, are modeled mathematically. To develop the demand response (DR) potentials of the farms, electrical storage systems, and self‐generation facilities, including thermal distributed generations and on‐farm solar sites, are addressed. In order to facilitate the integration of the agricultural DR programs into the electricity market, a mathematical formulation for agricultural demand response aggregator (ADRA) is suggested. The ADRA participates in the day‐ahead electricity market on behalf of the responsive farms. To overcome the price uncertainty of the electricity market, a robust optimization approach is addressed. This approach determines the robust decisions of farms in the worst‐case realizations of the uncertain electricity price. Regarding on‐farm solar sites located in rural areas, a data‐driven approach is used to estimate the solar power generation of a significant number of sites without needing to install costly communication and measurement infrastructures. Finally, the proposed approach is implemented on agricultural lands in the northeast of Iran. The numerical results show that the suggested approach provides day‐ahead peak shaving for the power systems meeting the crop's water requirements. [ABSTRACT FROM AUTHOR]

The reason for utilizing PV-T systems is their capability to generate both electricity and heat at the same time, which enhances energy efficiency and decreases the need for multiple energy sources. Considering the potential of solar energy and different climates in Iran, in this research, the feasibility, modeling, and comparison of the PV-T system to supply electricity and heat to residential units were investigated in 28 cities with 9 climates of Iran. A thorough evaluation of performance was conducted using the software Polysun 9.0 and PVsyst 6.6.8 for a duration of one year. The scientific novelty of this study relies on the simultaneous utilization of two analytical software, the thoroughness of the research, and taking into account the impact of climate on the findings. Investigations showed that the best performance of the designed system is related to Bandar Abbas and Zahedan, and the worst performance is related to Rasht and Sari. In general, according to the amount of electricity and heating produced by the PV-T system, it showed that Shiraz and Rasht stations have the highest and lowest production of energy. In terms of environmental effects, Birjand station will have the most and Rasht the least reduction in CO2 emissions. In terms of heating energy demand for the investigated building, Ardabil has the highest amount and Bandar Abbas has the lowest amount. [ABSTRACT FROM AUTHOR]

The gas turbine performance is highly sensitive to the compressor inlet temperature. The output of gas turbine falls to a value that is less than the rated output under high temperature conditions. In fact increase in inlet air temperature by 1°C will decrease the output power by 0.7% approximately. The solution of this problem is very important because the peak demand season also happens in the summer. One of the convenient methods of inlet air cooling is evaporating cooling which is appropriate for warm and dry weather. As most of the gas turbines in Iran are installed in such ambient conditions regions, therefore this method can be used to enhance the performance of the gas turbines. In this paper, an overview of technical and economic comparison of media system and fog system is given. The performance test results show that the mean output power of Frame-9 gas turbines is increased by 11 MW (14.5%) by the application of media cooling system in Fars power plant and 8.1 MW (8.9%) and 9.5 MW (11%) by the application of fog cooling system in Ghom and Shahid Rajaie power plants, respectively. The total enhanced power generation in the summer of 2004 was 2970, 1701 and 1340 MWh for the Fars, Ghom and Shahid Rajaie power plants, respectively. The economical studies show that the payback periods are estimated to be around 2 and 3 years for fog and media systems, respectively. This study has shown that both methods are suitable for the dry and hot areas for gas turbine power augmentation. Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper evaluates the performance of a geothermal heat pump in Iran. An air-to-air 5.275 kW heat pump has been changed and redesigned to a geothermal heat pump system for the first time in Iran. Air-to-air condenser has been replaced by a tube-in-tube heat exchanger and assembled system has been tested under ARI-325 standard at the national energy lab of Iran and the results have been compared with the original system. Then, local weather conditions and soil properties of Tabriz (located at the north-west of Iran) have been applied and geothermal coil has been designed. Coil has been connected to the heat pump and the average coefficient of performance (COP) of rather more than three has been recorded in cooling mode. Results obtained from experimental measurements show that horizontal GSHP systems can be used for Tabriz-like climates in Iran. Copyright © 2006 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Summary: Greenhouse gas emissions and increasing energy consumption motivate researchers toward using waste heat recovery. In the present study, a novel combined cooling and power (CCP) generation system driven by waste heat recovery of a steel factory in northeastern Iran is presented which uses an ammonia‐water mixture as the working fluid and consists of a vapor generator, a superheater, a turbine, an expansion valve, a mixer, a compressor, an evaporator, two recuperators, two condensers, and two pumps. In the presented system, a non‐isothermal phase change occurs in the vapor generator while an isothermal phase change happens in condensers. To evaluation of the system performance, comprehensive thermodynamic and thermoeconomic analyses are performed. The effects of generator pressure and ammonia concentration on the performance of the cycle are investigated. To satisfy different needs of users, the cycle is optimized by a genetic algorithm for different ratios of power to cooling capacity considering single and multi‐objectives and the best values of generator pressure and ammonia concentration are presented for each power to cooling ratio. The results show that based on the multi‐objective function, for heat source temperature of 573K the best conditions happen at power to cooling capacity ratio of 0.6, in which the optimum generator pressure and ammonia concentration are 43.87 bar and 79.49%, respectively. [ABSTRACT FROM AUTHOR]

Summary: The study presents an iterative structure for optimal allocating roof space to photovoltaic panels and solar water heaters to provide part of the energy demand of the building and supply the excess energy to the grid. This framework is based on a mathematical programming model and consists of six stages: demand model, optimum tilt angle, selection of energy conversion technologies, near shadow, planning and operation, and evaluation with a detailed model. The output of the proposed model is the optimal arrangement of photovoltaic panels and solar water heaters, type and capacity of cooling system, and operational issues including energy exchange between solar systems, electricity grid, natural gas network, and building and capacity factor of water circulation pump working between solar water heater system and central cooling‐heating system in each time step. Various constraints such as full supply of the building's energy demand, limited allocated space to solar systems installation, limited financial resources for investment in solar systems, technical constraints, etc, have been considered in this model. Eight different scenarios in terms of energy carriers prices, guaranteed renewable electricity purchase tariff, circulation pump operational cost, and investment costs for solar systems were examined. The results of using the proposed model on an office building show a water‐cooled absorption chiller cooling system is the optimal option with the ability to satisfy technical constraints. If the electricity generated from the photovoltaic panels cannot be sold to the grid, only the installation of solar water heaters with a capacity of 29 kW is optimal. In this case, the annual capacity factor of the system, considering the hot water demand, solar irradiation, and cost of running the pump, is 22.7%. Suppose it is possible to sell electricity to the grid due to a higher sale tariff than purchase one in Iran, in that case, only the solar panels with a capacity of 8.75 kW will be installed on the roof. [ABSTRACT FROM AUTHOR]

Summary: Nowadays energy demand has increased due to industrial development and population growth. On the other hand, attention to environmental issues has made it necessary to use renewable energy. The utilization of wind energy is emphasized due to low construction costs and rapid installation. Wind energy, on the other hand, can be stored via creating hydrogen because its power fluctuates at different times and is not uniform. The production of hydrogen and energy is essential to meet the needs of industries in different countries. Therefore, in this study, a comprehensive approach is presented to locating hydrogen production from wind energy using multicriteria decision‐making (MCDM). To implement the proposed approach, a case study in Iran and Hormozgan province is used. Hormozgan province is in good condition in terms of wind potential and many industries in this province need energy and hydrogen. The most appropriate factors were judged to be average wind speed, each region's number of refineries, and each region's rate of industrial development, with weights of 0.192, 0.167, and 0.141, respectively, using the stepwise weight assessment ratio analysis (SWARA) approach. The cities in Hormozgan province were then prioritized using the weighted aggregated sum product assessment (WASPAS) technique. Then, the sensitivity analysis of the ranking results was performed and The COmplex PRoportional ASsessment (COPRAS), additive ratio assessment (ARAS), and weighted sum methods (WSM) methodologies were then used to validate the results. For the development of hydrogen projects, Bandar Abbas was determined as the most suitable place. A 900‐kW turbine at Bandar Abbas will generate 532 730 kWh of power and 8620 kg of hydrogen annually. [ABSTRACT FROM AUTHOR]

Summary: The efficiency of photovoltaic cell is highly temperature‐dependent; therefore, the performance of these solar panels would be increased by decreasing the temperature. In this research, a novel integration of coupling thermal photovoltaic panels with thermoelectric generator module (PVT‐TEG) is investigated for possible application in reducing cell temperature in order to increase output electrical power, thermal efficiency, and overall efficiency of the integrated PVT‐TEG system. Initially, component validation is performed by experimental data with equipment in the energy laboratory for high reliability. In the hybrid system (PVT‐TEG), one‐third of a monocrystalline PV panel backside was equipped with thermoelectric generators (TEG), while aluminum water blocks were attached to the cold side of TEGs for cooling aim, then tested and compared with a simple panel at the same environment condition (Shahrood city in Iran) from August until September 2020. In this study, the influence of water velocity and its temperature are studied simultaneously. In addition, mathematical modeling is based on thermal resistance, whereas the impact of the thermal resistance of adjacent layers, TEGs, and the upper heat loss thermal resistance on the PVT‐TEG system and simple panel properties are investigated, respectively. Experimental and theoretical data are validated with obtained results from MATLAB and showed acceptable deviation error with less than 18%. The electricity generated in the PVT‐TEG panel is 8.5% more than a simple panel. TEG power generation has a small share of total power generation, so economic assessment is essential for industrial production. Finally, parametric analysis in PVT‐TEG estimates 70% higher total efficiency compared with conventional simple panel. [ABSTRACT FROM AUTHOR]

Summary: The main purpose of this study is to develop a sustainable smart energy management system for the desert climate, which aims to reduce energy expenses, energy consumption, and greenhouse gas (GHG) emissions via finding optimum power output and smart scheduling while considering users' uncertain behaviors. Moreover, the effectiveness of five metaheuristic optimization algorithms is analyzed and reviewed for presented system, which is modeled as a multiobjective function and contains over 1000 variables. The case study is city of Kashan located at the desert area of Iran with hot and dry climate. Presented system is established based on smart residential energy hub and home energy management system. Residential loads for a modern household are appropriately categorized and modelled. Ten different uncertain scenarios for users' energy consumption are simulated within the algorithm with considering users' comfort level simultaneously. Both energy cost and users' comfort deviation for studied multi‐energy system are formulated as a multiobjective function with two weighting factors. Our results present a comparison between different cases studied and the effects of uncertain power consumption on energy cost, comfort level, and computing time. Our findings indicate that the presented system with specified weighting factors is able to reduce energy expenses around 50% in different cases. Accordingly, due to a noticeable decrease in energy consumption, GHG emissions from fossil fuels are reduced remarkably considering the fact that only 1% of Iran's power supply is provided by clean energies. Results also illustrate that considering uncertainty has more effect on users' comfort level than energy cost. [ABSTRACT FROM AUTHOR]

Summary: People in the Middle East are facing the problem of freshwater shortages. This problem is more intense for a remote region, which has no access to the power grid. The use of seawater desalination technology integrated with the generated energy unit by renewable energy sources could help overcome this problem. In this study, we refer a seawater reverse osmosis desalination (SWROD) plant with a capacity of 1.5 m3/h used on Larak Island, Iran. Moreover, for producing fresh water and meet the load demand of the SWROD plant, three different stand‐alone hybrid renewable energy systems (SAHRES), namely wind turbine (WT)/photovoltaic (PV)/battery bank storage (BBS), PV/BBS, and WT/BBS are modeled and investigated. The optimization problem was coded in MATLAB software. Furthermore, the optimized results were obtained by the division algorithm (DA). The DA has been developed to solve the sizing problem of three SAHRES configurations by considering the object function's constraints. These results show that this improved algorithm has been simpler, more precise, faster, and more flexible than a genetic algorithm (GA) in solving problems. Moreover, the minimum total life cycle cost (TLCC = 243 763$), with minimum loss of power supply probability (LPSP = 0%) and maximum reliability, was related to the WT/PV/BBS configuration. WT/PV/BBS is also the best configuration to use less battery as a backup unit (69 units). The batteries in this configuration have a longer life cycle (maximum average of annual battery charge level) than two other configurations (93.86%). Moreover, the optimized results have shown that utilizing the configuration of WT/PV/BBS could lead to attaining a cost‐effective and green (without environmental pollution) SAHRES, with high reliability for remote areas, with appropriate potential of wind and solar irradiance. [ABSTRACT FROM AUTHOR]

Summary: Sustainable power sources, that is, the energy produced as of hydro control, biomass, wind, geothermal, sunlight, and sea resources deliberated as innovative choice intended to create clean energy and crisp water. The majority of the nations have challenged issues proceeding freshwater and power creation, which tends to the utilization of sustainable power source‐controlled desalination frameworks. In this work expanding the clean water accessibility that satisfies the load need, Hybrid Renewable Energy Systems (HRES) on the basis of Reverse Osmosis Desalination (ROD) is structured and then displayed. HRES is getting to be well known for power applications because of advances in sustainable power sources. Here, an innovative calculation based on Social Spider Optimization (SSO) is aimed at explaining the required optimization tasks. The technique referenced is turned out to be powerful, utilizing sustainable power source framework. The proposed system is contrasted with a genuine contextual analysis in the eastern part of Iran, Canary Islands and outcomes demonstrate that it has been successfully utilized thinking about both power quality and cost. Also, the outcomes acquired by the suggested technique are very encouraging to outline the capability and strength of the introduced methodology. [ABSTRACT FROM AUTHOR]

Summary: In this study, a two‐dimensional mathematical model is proposed for modeling the hollow fiber membrane (HFM) separators for hydrogen (H2) recovery unit implemented in the Razi Petrochemical Company (Imam Khomeini Port, Iran) to capture hydrogen from ammonia (NH3) purge gas. In this regard, computational fluid dynamics is applied to solve the equations of momentum and mass transfer in the laminar flow conditions. Axial and radial diffusion for mass transfer inside the membrane fibers and axial diffusion within the shell side of separator were considered. The distributions of concentration, velocity, and mass transfer fluxes were achieved by the model. As the new insights, the effects of feed flow rate and feed gas concentration on mass transfer of H2 were investigated. Moreover, fluid velocity profile and H2 fluxes in the tube (fiber), membrane, and shell sides of the HFM separator were studied. The results of simulation were compared with the industrial data and showed that the present developed model has excellent agreement with the experimental data with a low mean deviation value of 3.5%. [ABSTRACT FROM AUTHOR]

SUMMARY Gas turbine (GT) output power is affected by temperature, gas turbine inlet air-cooling systems are used to solve this. In the present work, the effect of using absorption chiller in GT power plants for two regions in Iran, namely Tabas with hot-dry and Bushehr with hot-humid climate conditions is conducted. Therefore, output power, first and second law efficiencies, environmental and electrical costs for GT power plant with inlet air cooler are calculated for two mentioned regions, respectively. Results show that using this system in hot months of a year is economical. In addition, using absorption chiller leads to increasing the output power 11.5 and 10.3%, for Tabas and Bushehr cities, respectively. Moreover, by using this method the second law efficiency is increased to 22.9 and 29.4% for Tabas and Bushehr cities, respectively. In addition, the cost of electricity production for Tabas and Bushehr cities decreases to about 5.04 and 2.97%, respectively. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]