Journal of Energy Management and Technology
Volume:2 Issue: 3, Summer 2018

The penetration level of distributed generations and renewable energy sources have been generally increased in power systems. However, such generation units with small capacities are not able to participate in electricity markets. Therefore, virtual power plant (VPP) concept is defined to integrate such power plants and cooperate them into power markets. A well-known type of distributed generation is combined heat and power (CHP) units, which has attracted significant efforts in recent years. In this paper, a VPP is modelled to obtain optimal participate into day- ahead market and response to local heat demand. The VPP includes wind power, two types of CHP units, NaS battery for electrical components and CHP units, heat storage, and boiler unit. Moreover, the stochastic model is accounted for scheduling of VPP to meat uncertainty of wind power units. The proposed stochastic model for the VPP is simulated, and the simulation results are reported and analyzed for evaluating the performance of the proposed model. The analysis proves the effectiveness and practicality of the proposed model is participation of VPP in electricity markets.

Nowadays architecture and construction faced with kind of identity crisis in Iran. Owing to this crisis, city buildings from architecture and physical design perspective are not compatible with any of rich and noble Iranian Islamic architecture criteria. In addition, this type of architecture are incompatible with sustainable and energy saving architecture. Quasi neo classic style is one of this architecture with no identity appearances that is popular with the affluent class of society. This style that is wrong and incomplete impression of western classic and neo classic architecture has rapidly become popular in Iran’s wealthy areas specially north Tehran. Reaching to the architecture with identity is an important aspect in contemporary buildings in Tehran and the main purpose of this research studies is to explain how to propagate the quasi neo classic style in contemporary buildings. Therefore the aim of this research is applied science with qualitative data. The method of this research is based on grounded theory using library material including books, handouts, essays and internet. In these research theoretical subjects in western neo classical architecture, its emergence in Iran with advantages and disadvantages for identity and Iranians sustainable architecture has been studied.

Optimal, safe and robust scheduling and planning of electric energy distribution networks are very important considering such networks as one of the most important components of electrical networks. Electric vehicles are one of the major features of the future electricity distribution networks. In this paper, an optimal robust model is proposed for short-term scheduling of distribution network in the presence of uncertainties to minimize the cost of network operation. The robust optimization (RO) method is applied in this research to address the uncertainty associated with power market price. To investigate the proposed method, a 33-bus IEEE-standard system has been applied, which contains distributed renewable generation units and non-renewable energy sources. The obtained results indicate the effectiveness of the proposed method in network scheduling in the presence of uncertainties. Also, the impact of electric vehicle parking as an energy storage system on the functional cost of the distribution network is discussed, which defines the practicality and high performance of the proposed model on scheduling of electric distribution networks.

Load growth, high penetration of distributed generators (DG) and energy storage systems (ESSs) have caused different challenges for the distribution networks (DNs) such as congestion in their lines. This paper assesses the impact of congestion on the operational cost of the multi microgrid (MMG) based DN firstly. Then, a security constrained energy management system (SC-EMS) for the MMG system is proposed by considering the effect of the network's load flow constraints on the scheduling of that. Obviously, adding extra constraints to the optimization problem of the MMG system leads to increment in the operational cost. In order to resolve this problem, tie lines between MGs are modelled. In fact, in the proposed model, MGs can trade energy not only with the DN, but also with other MGs. Moreover, it is evaluated that considering the MGs as an integrated unit decreases the overall operational costs. Simulations on a modified IEEE 33-bus test system with multiple MGs are performed in GAMS environment. As expected, the gained results demonstrate the increment in the operational costs of the DN and the MGs when the contingencies occur in the network's lines. On the other hand, taking the tie lines into account as a recommended solution leads to a decrement in the operational cost of the MMG system.

Available data indicate that close to two-thirds of the population of the Republic of Benin lacks access to electricity which has dire consequences on the country’s development agenda. Although electricity consumption has been increasing, the supply of electricity is not enough to meet the growing demand in the country. Managing electricity consumption in Benin has therefore become critical owing to the expected rise in the future consumption. This will help ensure future electricity security. Accordingly, this paper examines the determinants of electricity consumption for Benin using annual time series data for the period of 1971-2014. Estimation from the Autoregressive Distributed Lag model, the Fully Modified Ordinary Least Squares and the Canonical Co-integrating Regression reveal that population, urbanization, education and industrialisation positively affect electricity consumption for the country while income negatively reduces it. A further analysis using the rolling regression indicates that the effects of the above variables are time-varying with some social, political and economic changes. Among others, the paper recommends the need to increase awareness on environmental-energy issues; and the need for a policy to make new residential and non residential buildings that would be constructed in the urban centres especially, to be energy efficiently designed.

In this paper, a double input DC-DC converter based on modified Z-source converter is suggested for standalone PV/Battery system application. The configuration of double input DC-DC converter under one port powered off is presented to solve problem of randomness and intermittency in distributed power source. In the proposed topology, the input DC voltage is boosted and achieved higher voltage gain with lower voltage stress on power switches. Other merits of the proposed converter are that it operates with wide range of load, and input DC voltage sources supply DC load individually or simultaneously. The configuration of the proposed double input DC-DC converter is introduced and then, its operation principle is analyzed in detail. Switches voltage and current stresses are studied and then, calculation of voltage gain is performed for different states of the converter. Finally, simulation results are given to verify the theoretical analysis and performance of the suggested DC-DC converter.

Today, traditional networks are changing to active grids due to the burgeoning growth of distributed energy resources (DER), which demands scrupulous attention to technical infrastructures, as well as economic aspects. Providing energy services and spinning reserve in the market is one the features of this issue. In this study, from economic point of view, the aggregation of DERs in a distribution network to participate in joint energy and reserve markets is investigated. This approach, which is predicated upon price-based unit commitment method, has considered virtually all the technical data in the proposed model. It is worth to mention that uncertainties of loads market prices, as an inherent characteristic of the electricity markets, are treated in this study, and their effect on the operation of virtual power plants in energy and reserve markets has been thoroughly discussed. The innovation of this paper is to consider the uncertainty in connection between the virtual power plant and the upstream network, along with the mentioned uncertainties. To this end, in this paper, a 4-bus network is considered as a virtual power plant in which the condition of optimal operation of distributed generations, energy storage systems and removable load considering uncertainty in energy price and connection with upstream network and also, uncertainty in delivery of spinning reserve have been studied to maximize the profit of virtual power plant. Simulation has been carried out in MATLAB environment using teaching-learning based optimization algorithm (TLBO) for 24 hours on the proposed network.