جستجوی مقالات مرتبط با کلیدواژه « Energy Storage » در نشریات گروه « برق »

In this research, an optimal energy management model of a residential microgrid with the aim of resiliency and flexibility improvement is presented. Accordingly, a residential microgrid consisting of a solar power plant with energy storage system is considered. Each of houses in the microgrid has an electric vehicle. The residential microgrid is connected to the main grid and has been equipped with smart grid infrastructures. The outage of the main grid causes load shedding that consequently reduces the resiliency. Keeping the security of supply during these distortions is necessary. Therefore, in this paper, a new model of microgrid operation based on solar power plant and energy storage system is proposed. The efficiency of the proposed model is evaluated through numerical calculation of resiliency using a new index proposed in this paper. In addition, the proposed model improves the system flexibility. The amount of this improvement is evaluated using practical and accurate indicators including self-consumption and storage efficiency. The results show that the proposed model improves the resiliency in off-peak and peak hours by 4.7% and 9.75% respectively. Moreover, two indexes of flexibility, including self-consumption and storage efficiency, improve by 9.1% and 2.2% respectively.

Integrating renewable resources to provide local load has created a concept called microgrid. With the widespread introduction of microgrids, energy management and system utilization and resources in the electricity market are important tasks of microgrid management. In this paper, the problem of microgrid utilization is modeled taking into account economic, technical and uncertainties related to power consumption, wind speed and solar radiation in electricity market conditions. One of the most important issues in the electricity market is the discussion of the participation of units in real price conditions. In this paper, a framework for the exploitation of electricity and the consumption of controllable loads through integrated utilization of distributed energy sources of uncertainty is presented from a consumer perspective. The optimization problem is a two-step stochastic linear programming that minimized the cost of microgrid operation and expected cost of consumers considering the consumer’s requirement for controllable loads in the desire time interval and distribution company constraints that solved by using Salp swarm optimization algorithm. RBT and IBR tariffs are employed for modeling retail power market for better reflection of wholesale price volatility and avoid of the concurrent use of consumers. In this method price announced to the consumers by retailers only is limited specific later hours instead of the entire operation period. In this condition any timing of controllable loads need to price forecasting, while this forecasting have some uncertainties. These uncertainties are modeled using Monte Carlo method for stochastic price variable scenario generation. MATLAB software is employed for simulation and verification of the proposed method.

With the increasing use of renewable energy systems and the volatility of access to this type of energy, needs energy storage systems to sustain the system. In the meantime, energy storage systems have distinct characteristics and applications, one of which is the compressed air energy storage system. In the present paper, the newest researches and novel systems in the field of energy storage based on compression of air and their properties were compared with the classification and comparison of the system processes. The commonalities of all these systems are the use of compressed air or compressible fluid, to store energy as a mechanical potential. In terms of how the air is stored, these systems can be divided into three categories: isochoric, isobaric, and Liquefaction. For the complexity of the systems studied in this paper, they were classified into two major categories of compressed air energy storage, together with thermal storage and novel and hybrid systems. The development of compressed air energy storage systems with thermal storage seems more difficult because of the high capital cost. But the novel and hybrid systems, although slightly beyond existing technological frontiers by combining and integrating compressed air energy storage technology with other technologies such as city gate station systems, pumped hydro storage, and air liquefaction can play a significant role in the energy storage landscape.

Solar energy is a desirable type of renewable energies. However, it should be stored due to the sun radiation discontinuity. Phase-change materials (PCMs) store the thermal energy through their phase transitions, and the optimization of their thermal properties leads to more efficient thermal storage. In this study, paraffin wax was used as a PCM and aluminum oxide, and copper nanoparticles were used to improve its thermal properties. The morphology of the nanocomposites was studied with Field Emission Scanning Electron Microscopy (FESEM). Experiments were conducted in a factorial arrangement in a completely randomized design with three main factors, including: the weight percentage of nanoparticles (three levels), the type of nanoparticles (two levels), and the size of the nanoparticles (three levels), and pure Paraffin wax as a control sample. The melting point and the latent heat of each sample were measured with differential scanning calorimetery (DSC). The results showed that by an increase in nanoparticles concentration, the melting point of nanocomposites decreased slightly. On the other hand, the type and size of nanoparticles had no significant effect on the melting point. The addition of nanoparticles increased the latent heat of nanocomposites noteworthy in an optimal concentration. With a decrease in the nanoparticles size, the latent heat of nanocomposites increased. The nanocomposite sample which was filled with copper nanoparticle at the concentration and size of 1% and 30 nm respectively, had the highest latent heat.

In recent years, the exploitation of the energy storage systems has attracted many researchers in the electricity industry. Due to the relatively high cost of storage, usually many investors are not being prevented from installing and operating in a power system. In this paper, the effect of the type of operation of the energy storage system (the whole year or part of the year) on the profit of the energy arbitrage (shift) in the electricity market is investigated by an electrical energy storage system. For Evaluation the effect of the price prediction error on the energy arbitrage revenue, two types of prices (real price, 3 Hour Ahead Predispatch Prices) have been used. Due to the encouragement of private investors, it is proposed to use the loan for the initial investment cost so that the proposed plan for the investor is economically justified. Due to high investment costs and longer lifespan of the energy storage system, the number of charging and discharging energy is one, which is the time of charging at the lowest cost of energy and the time of discharge at the highest energy cost to increase energy returns.