Journal of Energy Management and Technology
Volume:2 Issue: 1, Spring 2018

The main objective of this paper is to express the positive features of renewable energy and the necessity to substitute fossil fuels, especially oil, with these novel sources of energy. Nonetheless, the crucial question which should be answered primarily is “what are the key advantageous of renewable energy, especially in countries like Iran with considerable and inexpensive underground resources like oil and natural gas?”. Renewability, flexibility, cleanliness and creation of new job opportunities are some of the most significant benefits of renewable energy. In addition, this type of energy not only does not suffer from fossil fuels drawbacks but also provides some benefits for countries. While dependency on oil challenges the security of countries in various areas - political, economic, social and environmental – the new alternative energy provides sustainable development and security for their consumers. This matter will be discussed throughout three parts in this paper by aid of descriptive-analytical method. The result, with emphasis on Iran, will demonstrate there is no alternative to these new, clean and renewable energy sources.

Green electrical power resources, especially wind farms have ascending growth in power generation technologies. Although growing trend of wind farm penetration is beneficial from environmental view of point, wind speed uncertain nature and fluctuations threaten system reliability and security. Energy storage systems are good choices as backup for such systems with high volatility. The main concern of this paper is about solving stochastic security constraint unit commitment (SCUC) problem in presence of wind farms and storage systems and modelling of storage systems in Benders decomposition method. To achieve a robust solution, the SCUC problem is solved by a scenario based method in which benders cuts are generated to remove congestion from electrical power lines and check feasibility and optimality of the solution in all scenarios. To generate Benders cuts, security, feasibility and optimality sub-problems have been formulated and solved in an iterative structure. Wind power scenarios are generated by Monte Carlo sampling method and followed by a scenario reduction technique to reduce computation burden. Investigating the simulation results on a six-bus standard test system demonstrates economic advantages of the proposed method while power system technical and security constraints are satisfied

The thermal partial oxidation process of methane was investigated experimentally. Compared with the other reforming technologies partial oxidation process has several advantageous. There is no need for external heat sources and additional feeds like water as in steam reforming. Moreover, the process is catalyst free and thus catalyst deactivation problems are completely out of consideration. Thermodynamic calculations and kinetic simulation were performed to determine the practical operating conditions. Experimentally, a porous material-based reactor was built to perform the partial oxidation process. Al2O3 granular with different size selected as porous structures and installed in the reaction zone. Physical parameters include diameter of the rector is considered for other experimental test. As the result the temperature profiles along the reactor central axis and concentration profiles of CO and H2 were measured. Also the effects of equivalence air ratio on the reforming process were investigated. Different equivalence air ratio 1.5 and 2 was considered to perform the partial oxidation process.

This paper presents a theoretical framework for selecting of appropriate working fluids for basic Organic Rankine Cycle (ORC) and three modified ORCs based on their thermodynamic properties. A comprehensive thermodynamics analysis is done for basic ORC, modified ORC incorporating turbine bleeding, regenerative ORC, and ORC incorporating both turbine bleeding and regeneration using 8 different working fluids (R113,R141b, n-pentane, R123, R245fa, R600, isobutane, R236fa). Among these analyzed working fluids, R113 and R236fa present the highest and lowest thermal efficiency. The thermal efficiency can be much higher when the modified ORC incorporating both turbine bleeding and regeneration is used. Of course, among of the presented working fluids, there are environmentally-friendly working fluids, too, which can be a good choice for the environmentally consideration issues. At the end, we will also present a parametric study for crucial parameters in the cycle. With this study, we can find a specific range for the evaporator pressure in which the condenser duty and net produced power will be minimum and maximum, respectively. In fact, we will present an optimum value for the pressure of evaporator using different working fluids for the purpose of the condenser duty minimization and the net produced power maximization. The optimum value for the pressure of the evaporator in this case will range from 2.778 to 3.656 MPa.

Energy storage system (ESS) is generally used to manage the intermittency of the renewable energy sources (RESs). One of the important issues in microgrids is to supply high quality powers to consumers. This paper proposes the use of hybrid energy storages to improve the power quality under unbalanced load conditions for microgrids applications. Battery and SC are used as hybrid energy storages systems (HESSs) that provide low and high power frequency respectively. The proportional resonance(PR) and fuzzy controllers are, respectively, used to regulate the AC load voltage and DC bus voltage controller. The main advantages of the proposed energy management scheme are to reduce battery power fluctuations, better DC bus voltage regulation for generation and load disturbances, improvement system performance under unbalanced load conditions, reduced rate of charge/discharge of battery current, improved power quality feature under unbalanced load and transition conditions. The performance of the proposed method and control strategy is verified by using simulation studies in the MATLAB software environment.

The motivation of current research study is the way of diagnosing and ranking risk factors of a completed real-world gas injection project. A Nominal Group Technique is used to establish a Risk Matrix Structure, and to identify risk factors. Next, a hybrid group Eigen Vector Method and Simple Additive Weighting is applied to assign the weighs to risk factors. In this procedure, it is assumed that risk factors influence on the project constraints which are scope, quality, cost and time. Moreover, at the whole assessment stages, the opinions of twelve experts are utilized through several expertise meetings. The results indicate that the top-ten risk factors are: Poor or nonexistent project management system in the project; Bad estimation of Scope of Work; Lack of frozen requirements; Lack of cooperation among consultants, suppliers or subcontractors; Overemphasis of technical specifications in design; Conduct planning without a view on the project priorities; Inadequate/Invalid project assumptions; Failure to receive requirements from the client; Lack of people skills in the project leadership; and Absence of precise/accurate information.

Optimal placement and sizing of distributed generation (DG) is one of the important issues in the radial distribution system, playing a vital role in reduction power losses and total cost of the system. Optimal placement and sizing of DG have many advantages for the radial networks, which some of the important them are the reliability and voltage stability improvement, power loss and emission reduction. In this paper, Exchange market algorithm (EMA) as a new heuristic algorithm is used for solving multiple DG placement and sizing problem in the radial distribution system. EMA is consisted of two powerful searcher operators which are used to create and organize the random numbers of the initial population and it can be employed to find the optimum point in the optimization problems. In order to evaluate the purposes of this study, EMA is applied on three test systems, including 33, 69 bus IEEE test system and 94 bus Portuguese radial distribution system. The obtained numerical results of the optimization procedure are compared with recent studies in this regards and the resulting analyses indicated that the power losses in the radial network reduced to the minimum amount of ownership. The results also prove the effectiveness of the EMA as one of the powerful optimization tools in solving DG placement problem.