نشریه سیستم های انرژی پایدار
سال دوم شماره 1 (زمستان 1401)

In recent years, energy shortage and environmental pollution have greatly promoted the rapid development of electric vehicles in the industry. With the growing importance of environmental issues, replacing fossil fuel sources with renewable energies has become a necessity. A large part of environmental pollution is related to the transportation sector. Replacing fossil fuel vehicles with electric vehicles is a suitable solution to reduce environmental pollution and energy consumption. The development of electric vehicles in Iran has many challenges, such as charging stations, the high price of electric vehicles, low mileage, and most importantly, the cheap price of fuel. Therefore, in this article, the scenarios of the development of electric vehicles in Iran are examined. For this purpose, 4 scenarios are defined in Vensim software. In these scenarios, two important parameters of fuel price and environmental issues are considered. The results show that fuel price reform will lead to faster growth of electric vehicles and the higher the slope of fuel price reform will lead to faster growth of electric vehicles. Also, the results show that the environmental problem alone cannot be the reason for the rapid growth of electric vehicles in Iran, but as a primary parameter, it plays a significant role in the growth of these cars.

This article deals with the optimization of blackout management methods in electricity distribution networks. For this purpose, keying methods, the use of distributed production, and load response have been examined from an economic perspective. For this economic analysis, the cost of a power outage, which includes the cost of human resources, vehicles, and undistributed energy, has been calculated. Considering the key role of duration and unsupplied load in the cost of a power outage, outage management solutions have been modeled. Then, the effect of important parameters such as electricity price has been investigated by sensitivity analysis. The proposed model has been implemented in the Big Tehran Electricity Distribution Company. In the first part, the economic modeling of power outages in the distribution network is introduced. The model calculates things like fines set by the government, the cost of human resources, accident vehicles, and the cost of automation of distribution stations. In the second part, fines and temporary energy supply are optimized. Two approaches are considered for the short supply of energy. The first method is demand-based and load-reduction in reward returns. The second method is to purchase power from distributed sources (DGS) in the outage area. In the third part, the sensitivity of the temporary energy supply to the price provided by the distribution company is considered and its effect on optimization is investigated.

Today, the utilization of energy storage systems, especially in distribution systems, has a significant impact on improving the performance of the energy system, improving system reliability indicators, and reducing energy system operating costs. Therefore, using these utilities in the energy systems is advantageous. In this paper, the motivations for using electric vehicles as energy storage units are investigated. For instance, we can mention the effect of minimizing system costs from the load point of view. Moreover, in this paper, the effect of electric vehicles in improving the reliability indices, such as the Energy Not Served (ENS) and the System Average Interruption Duration Index (SAIDI) has been investigated. In order to achieve this, a dynamic planning framework has been introduced in a distribution network with the aim of minimizing system costs. After applying the framework presented in the article and modeling the IEEE 34-node sample system, the simulation results show that the network operator improves the network reliability indicators by adjusting the electricity price in such a way that electric car owners can benefit. In this regard, the total amount of ENS of the system is reduced by 11% in centralized mode. Also, the SAIDI index is reduced by 85% in the centralized mode and by 51% in the distributed mode.

The flat plate solar collector as a heat exchanger is responsible for absorbing the radiant energy of the sun and transferring heat to the working fluid. Water and air are among the most common fluids that flow as the working fluid among these collectors. Considering that efficiency is one of the most important criteria in the evaluation of these collectors, in this study, four fluids from the group of organic liquids and therminol oils were selected and their thermal performance was investigated on the efficiency of a flat plate solar collector. The results obtained in this article show that organic liquids are more efficient compared to therminol oils and have better performance in absorbing heat from the collector and transferring it to the working fluid, and the reason for this is the lower specific heat of organic liquids. It is raised at working temperature. Also, with the increase in the intensity of solar radiation, the energy efficiency and exergy of the collector will decrease and the amount of heat transferred from the working fluid to the collector will increase, and with the increase of the ambient temperature, the exergy efficiency and useful exergy of the collector will decrease. The average values of energy efficiency and exergy due to the choice of working fluid in this design show that organic liquids can be the best working fluid in these type of collectors after water.

This research simulates a geothermal heat pump system needed to grow hemp plants for medical applications in Ardabil, Iran. Supplying energy for the cultivation of hemp plants can sometimes impose many costs. On the other hand, it is impossible to ignore the release of carbon dioxide to produce energy for the cultivation of this plant. In this regard, in this article, we will check the performance of a geothermal heat pump system and evaluate its output for cultivating the Hemet plant in the greenhouse. The results show that considering the cultivation of industrial hemp twice a year, the equivalent of 17.74 to 26.62 tons of carbon dioxide is saved per hectare. According to the 4 hectares under cultivation in the designed greenhouse, a figure equal to 70.96 to 106.48 tons of carbon dioxide per year is stored due to hemp plant cultivation in the greenhouse. In addition, using a heat pump system equivalent to 6.64 tons of oxide prevents the emission of greenhouse gases through renewable energy, which creates a negative carbon greenhouse system. Also, the heat capacity of the geothermal pump to supply energy to the greenhouse is equal to 570.2 kilowatts, which is dependent on the height and optimal temperature of the greenhouse. With the increase of these design parameters, the required heat capacity also increases.

This study analyzes the water-energy-environment nexus by simultaneously evaluating the potential of microalgae for phycoremediation, biofuel production, and carbon capture. The LEAP software was employed to investigate the treatment and biodiesel production capacity. The impact of replacing biofuel in the urban public transportation system, considering different mixing ratios of biodiesel including B5, B10, B20, and B50, was also studied using EnergyPLAN software. The results showed that the produced biodiesel with these ratios could provide 4.25%, 8.58%, 17.43%, and 45.78% of the total annual energy requirement, respectively. These replacement rates correspond to a reduction of 2.9%, 5.9%, 12.7%, and 31.7% in CO2 emissions. Furthermore, assuming a 5% annual growth rate in the input of the wastewater treatment plant, after 12 years, the proposed model can reduce the annual carbon emission costs by $414 million while meeting 46% of the annual energy demand using B50 and decrease annual CO2 emissions by 32%.