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[en] In this paper a multi-objective genetic algorithm is used to solve a multi-objective model to optimize the time allocation of domestic loads within a planning period of 36 h, in a smart grid context. The management of controllable domestic loads is aimed at minimizing the electricity bill and the end-user’s dissatisfaction concerning two different aspects: the preferred time slots for load operation and the risk of interruption of the energy supply. The genetic algorithm is similar to the Elitist NSGA-II (Nondominated Sorting Genetic Algorithm II), in which some changes have been introduced to adapt it to the physical characteristics of the load scheduling problem and improve usability of results. The mathematical model explicitly considers economical, technical, quality of service and comfort aspects. Illustrative results are presented and the characteristics of different solutions are analyzed. - Highlights: • A genetic algorithm similar to the NSGA-II is used to solve a multi-objective model. • The optimized time allocation of domestic loads in a smart grid context is achieved. • A variable preference profile for the operation of the managed loads is included. • A safety margin is used to account for the quality of the energy services provided. • A non-dominated front with the solutions in the two-objective space is obtained
[en] This design is intended to revive and utilize fundamental principles of tall buildings into a modern design of an 80-story residential tower in Doha. The main goal in this design is to create an innovative and next generation sustainable tower design specifically for the Middle East by taking advantage of cutting-edge technologies while respecting the traditional way of living that reflects the cultural roots. The design utilizes a vertical exterior cable system which is used as a shading device and contributes significantly to the structural lateral load resistance. -- Highlights: → Linguistically paper has been checked and marked up with blue color as can be seen on marked-up manuscript. → All grammar corrections from reviewers have been made on manuscript with red colors. → On page 6 paragraphs has been added to explain e-QUEST basics. → References are being updated. → Fonts in have been changed.
[en] We examine the ability of electrical pulses to execute a highly stable propagation in a special electrical network made of concatenated pieces of discrete electrical lines with alternately positive and negative signs of the second-order dispersion. We show that such networks, called dispersion-managed electrical lines, induce a pulse breathing phenomenon, that is a dynamical behaviour with alternate regimes of pulse broadening and compression. This breathing phenomenon, which prevents the pulse from broadening without bounds during propagation in the network is the most appealing feature of the technique of dispersion management developed in the last decade in the area of optical communications. Meanwhile, we show that the benefit of using dispersion management in ETLs is strongly mitigated by the third-order dispersion and the losses at the junction points between adjacent pieces of line. These come into play as major factors of impairment for the pulse robustness with a much stronger impact than in dispersion-managed optical transmission lines.
[en] ECNG Inc. is a full service provider of independent and objective energy advice and management services to industrial, commercial and institutional end-users of all forms of energy. ECNG manages 10 per cent of the Ontario gas market and expects a 10 per cent share of electricity (14 TWh). ECNG has a balanced portfolio with expertise in both petroleum and electricity sectors. The company has also dealt extensively with retailers, marketers, wholesalers and suppliers on issues regarding deregulation
[en] Highlights: • A new multi-agent based distributed control architecture for energy management. • Multi-agent coordination based on non-cooperative game theory. • A microgrid model comprised of renewable energy generation systems. • Performance comparison of distributed with conventional centralized control. - Abstract: Most energy management systems are based on a centralized controller that is difficult to satisfy criteria such as fault tolerance and adaptability. Therefore, a new multi-agent based distributed energy management system architecture is proposed in this paper. The distributed generation system is composed of several distributed energy resources and a group of loads. A multi-agent system based decentralized control architecture was developed in order to provide control for the complex energy management of the distributed generation system. Then, non-cooperative game theory was used for the multi-agent coordination in the system. The distributed generation system was assessed by simulation under renewable resource fluctuations, seasonal load demand and grid disturbances. The simulation results show that the implementation of the new energy management system proved to provide more robust and high performance controls than conventional centralized energy management systems.
[en] Liberalisation of the energy markets, shifting emphasis from energy carriers to energy products, improving insights in the areas of saving energy and energy efficiency, changes in the company itself. These are the developments which will continue to influence the profession of energy consultant, according to the author. A brief impression is given of what the energy consultant can do in the year 2000
[en] The Energy Management Control System (EMCS) for Sheppard AFB was started in 1976 with contract completion in 1981. With other additions the system grew to over 8,000 points with 350 Field Panels. Over 35 miles of coax for data transmission were installed. In 1987 an effort was started to move to the open-quotes newclose quotes generation for the central system. At the same time coax replacement with fiber optics was started. This paper discusses the problems encountered which caused a change in plans and a move to 3rd generation system. There are many things to consider when attempting an upgrade. Conflicting information will make the task that much harder. This paper will attempt to show some of the problems encountered and lessons learned to help others avoid such difficulties
[en] Research highlights: → A new FMCS architecture with an energy management system was developed. → The new coupling system was demonstrated feasible during in situ experiments. → A survey found that HVAC is the most energy intensive system in IT industries. → A 9.6% chiller efficiency increase and total 23.2% annual energy saving were reached. - Abstract: A commissioning unit with an energy management system (EMS) was developed to be used together with facility monitoring and control systems (FMCS). This paper describes the testing of the new coupling system, in which a detailed management program is embedded for real time control decision making. First, a survey was conducted to evaluate the current power consumption of the facility systems, and found that HVAC is the most energy intensive system. Then a case study was performed, while the plant was in operation, to demonstrate the feasibility of the new coupling system, and a 9.6% chiller efficiency increase and total 23.2% annual energy saving for the chillers were reached, by optimizing the part load ratio condition of chillers and pumps. The results from in situ experiments show that applying this energy management system to the IT industry is feasible. A better custom-made FMCS with EMS, and full scale testing to greatly increase the overall energy efficiency, is recommended.