Results 1 - 10 of 1423
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[en] This document describes Bechtel Hanford, Inc.'s approach for developing performance objectives, measures, and indicators designed to reflect company performance against U. S. Department of Energy performance objective/measure 1
[en] Highlights: ► Analyze mutual interactions and restrictions within energy management systems. ► Tackle uncertainties expressed as fuzzy sets, and regular and radial intervals. ► Obtain optimal solutions under preferred satisfaction degrees and system benefits. ► Use protection level to reflect tradeoffs between constraint-violation and system reliability. ► Provide decision makers with effective energy management schemes. - Abstract: In this study, a fuzzy radial interval linear programming (FRILP) model was developed for supporting robust planning of energy management systems with environmental and constraint-conservative considerations, facilitating the reflecting of multiple uncertainties that are existing in energy activities and environmental emissions and could be expressed as fuzzy sets, and regular and radial intervals. Particularly, it could ensure the generation of robust solutions that would be feasible with high probability under input data variations, reflecting tradeoffs between the conservatism levels of solutions and probability levels of constraint violation. Specifically, 24 radial intervals associated with the electricity generation efficiency and electricity demands under different protection levels based on the natural and technologic conditions, as well as decision makers’ expectation were determined. Totally, 30 scenarios under the combinations of five protection levels were analyzed. Through solving the developed model, the results showed that decision variables would be rising with the increase of protection levels and higher radii fluctuation levels of radial intervals would cause higher system cost and lower satisfaction degree. The generated solutions could offer detail energy management plans (e.g., energy conversion technology capacity expansions) for decision makers, and thus could guarantee optimal economic and environmental benefits under desirable system reliability.
[en] Energy management is a system of managing energy utilization wisely and it includes issues such as energy efficiency (conservation), use of renewable energy, use of technology and development of energy policy. Its benefits has been well known for cost reduction and increase competitiveness and also other indirect impact such as preserving the natural resources and reduction of green-house gases. Although various strategies have been formulated by the government for the industries to adopt energy management, the result seems to be minimal and stagnant in some ways due to the various barriers which exists. Industries on the other hand, have successfully welcomed two famous management system namely the Environmental Management System ISO 14000 and the Quality Management System ISO 9000 to be implemented at their premises. This paper shows how energy management system can be effectively implemented by comparing similar generic management elements of energy management to ISO 9000/14000 standards. The seven (7) elements of energy management system discussed are top management commitment, policy establishment, energy management team, energy audit, energy efficiency projects, monitoring and training
[en] Transition countries include a group of countries with similar political, economic and social problems that signify the period after the end of the cold war and the fall of Communism. The paper presents the characteristics of the European Communist countries before and after the fall of the iron curtain, which influenced the transition process toward market economy. The centralist (Russian) economy model had enormous advantages at the beginning, particularly in the energy sector, owing to unlimited consumption of blood, sweat and tears during the construction of major power plants. The bureaucratic system executed ruthless expropriation of land and the existing power system, neglecting the environment and human health and even disregarding the feasibility of new power plants. The market creation and particularly the creation of an energy market, under which we understand selling and buying of all forms of energy, fuels, power plants' equipment and capital for energy sector, asks for a series of tasks from the Eastern European countries. They must accept market rules, standards of highly industrialised western countries and achievements in parliamentary democracy as the canon of behaviour in democracy. Setting up a legal infrastructure for the private sector, devising a taxation system, determining ownership rights, stabilising the macro economy in the sense of managing the government budget so as to avoid an excessive fiscal deficit, and stabilising monetary policy are primary tasks of the transition countries. The paper particularly reviews the tasks specifically related to the energy sector and analyses the problems taking into account national strategic interests. (author)
[en] The paper analyzes the energy sector in the period from 1990 to 2005. What is shown here through an analysis of political, economic, energy, technological and institutional processes, and based on actual developments and non-developments, the consequences on energy situation to be evolved in the next 15 years, are analyzed. A crucial characteristic of this period is the fact that consumption growth is more distant from the trends in the developed countries and is increasingly approaching ones occurring in developing and undeveloped countries. The other such characteristic is lack of technological progress, which could generate desirable structural changes in energy production and demand. Taking in consideration what has been accomplished so far and what has not been accomplished, we cannot expect in the coming period the changes that could significantly modify the relations in the structure of energy production and demand. Keeping the balance between production and demand will be increasingly difficult, as well as keeping the influence on energy prices which will be growing. In this, it is more than ever indispensable that the state takes up its role.(author)
[en] This paper presents the results of 11 after-hours walk-throughs of offices in the San Francisco CA and Washington D.C. areas. The primary purpose of these walk-throughs was to collect data on turn-off rates for various types of office equipment (computers, monitors, printers, fax machines, copiers, and multifunction products). Each piece of equipment observed was recorded and its power status noted (e.g. on, off, low power). Whenever possible, we also recorded whether power management was enabled on the equipment. The floor area audited was recorded as well, which allowed us to calculate equipment densities. We found that only 44 percent of computers, 32 percent of monitors, and 25 percent of printers were turned off at night. Based on our observations we estimate success rates of 56 percent for monitor power management and 96 percent for enabling of power management on printers
[en] Highlights: • In this paper an expert energy management system (EEMS) is presented. • A power forecasting module for wind generation capacity is presented. • The objective functions that must be minimized are operating cost and net emission. • A smart energy storage system (EES) for electrochemical batteries is presented. • A new modified Bacterial Foraging Optimization (MBFO) algorithm is presented. - Abstract: Recently, the use of wind generation has rapidly increased in micro-grids. Due to the fluctuation of wind power, it is difficult to schedule wind turbines (WTs) with other distributed energy resources (DERs). In this paper, we propose an expert energy management system (EEMS) for optimal operation of WTs and other DERs in an interconnected micro-grid. The main purpose of the proposed EEMS is to find the optimal set points of DERs and storage devices, in such a way that the total operation cost and the net emission are simultaneously minimized. The EEMS consists of wind power forecasting module, smart energy storage system (ESS) module and optimization module. For optimal scheduling of WTs, the power forecasting module determines the possible available capacity of wind generation in the micro-grid. To do this, first, an artificial neural network (ANN) is used to forecast wind speed. Then, the obtaining results are used considering forecasting uncertainty by the probabilistic concept of confidence interval. To reduce the fluctuations of wind power generation and improve the micro-grid performances, a smart energy storage system (ESS) module is used. For optimal management of the ESS, the comprehensive mathematical model with practical constraints is extracted. Finally, an efficient modified Bacterial Foraging Optimization (MBFO) module is proposed to solve the multi-objective problem. An interactive fuzzy satisfying method is also used to simulate the trade-off between the conflicting objectives (cost and emission). To evaluate the proposed algorithm, the EEMS is applied to a typical micro-grid which consists of various DERs, smart ESS and electrical loads. The results show that the EEMS can effectively coordinate the power generation of DERs and ESS with respect to economic and environmental considerations
[en] Highlights: • Improving the utilization of wind power by the demand response of residential hybrid energy system. • An optimal scheduling of home energy management system integrating micro-CHP. • The scattered response capability of consumers is aggregated by demand bidding curve. • A stochastic day-ahead economic dispatch model considering demand response and wind power. - Abstract: As the installed capacity of wind power is growing, the stochastic variability of wind power leads to the mismatch of demand and generated power. Employing the regulating capability of demand to improve the utilization of wind power has become a new research direction. Meanwhile, the micro combined heat and power (micro-CHP) allows residential consumers to choose whether generating electricity by themselves or purchasing from the utility company, which forms a residential hybrid energy system. However, the impact of the demand response with hybrid energy system contained micro-CHP on the large-scale wind power utilization has not been analyzed quantitatively. This paper proposes an operation optimization model of the residential hybrid energy system based on price response, integrating micro-CHP and smart appliances intelligently. Moreover, a novel load aggregation method is adopted to centralize scattered response capability of residential load. At the power grid level, a day-ahead stochastic economic dispatch model considering demand response and wind power is constructed. Furthermore, simulation is conducted respectively on the modified 6-bus system and IEEE 118-bus system. The results show that with the method proposed, the wind power curtailment of the system decreases by 78% in 6-bus system. In the meantime, the energy costs of residential consumers and the operating costs of the power system reduced by 10.7% and 11.7% in 118-bus system, respectively.
[en] An energy management system with an electronic gearshift and regenerative braking is presented to improve the gross efficiency and driving range of an electric scooter, driven directly by a four-phase axial-flux DC brushless wheel motor. The integration of stator windings, batteries, ultracapacitors, and a digital controller constitutes an energy management system, which features smooth electronic gear shifting and regenerative braking. The gross efficiency of the experimental scooter is improved in the drivable range by 20% with respect to that without regenerative braking. The battery-to-wheel efficiency was also above 70% for both low- and high-speed gears.