912 resultados para ENERGY RESOURCES


Relevância:

70.00% 70.00%

Publicador:

Resumo:

The increasing and intensive integration of distributed energy resources into distribution systems requires adequate methodologies to ensure a secure operation according to the smart grid paradigm. In this context, SCADA (Supervisory Control and Data Acquisition) systems are an essential infrastructure. This paper presents a conceptual design of a communication and resources management scheme based on an intelligent SCADA with a decentralized, flexible, and intelligent approach, adaptive to the context (context awareness). The methodology is used to support the energy resource management considering all the involved costs, power flows, and electricity prices leading to the network reconfiguration. The methodology also addresses the definition of the information access permissions of each player to each resource. The paper includes a 33-bus network used in a case study that considers an intensive use of distributed energy resources in five distinct implemented operation contexts.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

The development in power systems and the introduction of decentralized generation and Electric Vehicles (EVs), both connected to distribution networks, represents a major challenge in the planning and operation issues. This new paradigm requires a new energy resources management approach which considers not only the generation, but also the management of loads through demand response programs, energy storage units, EVs and other players in a liberalized electricity markets environment. This paper proposes a methodology to be used by Virtual Power Players (VPPs), concerning the energy resource scheduling in smart grids, considering day-ahead, hour-ahead and real-time scheduling. The case study considers a 33-bus distribution network with high penetration of distributed energy resources. The wind generation profile is based on a real Portuguese wind farm. Four scenarios are presented taking into account 0, 1, 2 and 5 periods (hours or minutes) ahead of the scheduling period in the hour-ahead and realtime scheduling.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

An intensive use of dispersed energy resources is expected for future power systems, including distributed generation, especially based on renewable sources, and electric vehicles. The system operation methods and tool must be adapted to the increased complexity, especially the optimal resource scheduling problem. Therefore, the use of metaheuristics is required to obtain good solutions in a reasonable amount of time. This paper proposes two new heuristics, called naive electric vehicles charge and discharge allocation and generation tournament based on cost, developed to obtain an initial solution to be used in the energy resource scheduling methodology based on simulated annealing previously developed by the authors. The case study considers two scenarios with 1000 and 2000 electric vehicles connected in a distribution network. The proposed heuristics are compared with a deterministic approach and presenting a very small error concerning the objective function with a low execution time for the scenario with 2000 vehicles.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

Energy resource scheduling is becoming increasingly important, as the use of distributed resources is intensified and of massive electric vehicle is envisaged. The present paper proposes a methodology for day-ahead energy resource scheduling for smart grids considering the intensive use of distributed generation and Vehicle-to-Grid (V2G). This method considers that the energy resources are managed by a Virtual Power Player (VPP) which established contracts with their owners. It takes into account these contracts, the users' requirements subjected to the VPP, and several discharge price steps. The full AC power flow calculation included in the model takes into account network constraints. The influence of the successive day requirements on the day-ahead optimal solution is discussed and considered in the proposed model. A case study with a 33-bus distribution network and V2G is used to illustrate the good performance of the proposed method.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

The Iowa Economic Development Authority (IEDA) Energy Office sets energy policy direction for Iowa and receives designated funding from the State Energy Program Formula from the Department of Energy to carry out designated energy activities. These activities include promoting energy efficiency, biofuels and renewable energy.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

The thesis presents a comparison of the national energy policies of the Federal Republic of Germany and Canada from 1973 until the late 1980s. The purpose of this paper is to analyze whether economic and/or environmental concerns were responsible for changes in the· West-German and Canadian national energy policies. Furthermore, the feasibility of implementing a soft energy path in West-Germany and Canada is examined. For better comprehension of the policy-making process and implemented changes in the national energy policies of the two states, the West-German and Canadian parliamentary systems and the political cultures were compared. For the analysis, several events with international impact were taken as guidelines. Furthermore, based on statistical data, the West-German and Canadian energy production and consumption were analyzed. With reference to these results the degree of the de facto changes in the national energy policies were analyzed. In addition, the thesis discusses the possibilities which a soft energy path offers to both national governments to renounce themselves from the dependencies on a few energy resources. The thesis reveals that changes in the West-German and Canadian national energy policies, in their energy production and consumption are correlated to various world events. In particular, governmental reponses security of energy supply by the two international oil crises of 1973 and 1979/1980 demonstrate that changes in the West-German and Canadian national energy policies were implemented in reaction to economic concerns than environmental ones. With the policies "away from oil" and "off oil", the West-German and Canadian government implemented the i i substitution of oil through various diverse energy supply resources. However, energy savings concepts and policies were initiated through the first oil crisis in 1973. The world recessions in 1975 and 1982 had no 'profound impacts on the agenda of West-German and Canadian energy policies. As a consequence of the stagnation or the negative growth of the world economic market, changes in their energy production and consumption can be perceived. However, the West-German and Canadian energy production and consumption intensified with the augmentation of the world economy. During the period of study, environmental concerns were taken into account in the energy policy agendas of the Federal Republic of Germany and Canada but they were not of primary concern. wi thin the decade of. the 1980s notably more environmental considerations were taken into account in the energy policies of the two states. The two nuclear reactor accidents in 1979 and 1986 sharpened to various degrees West-German and Canadian public discourse of present energy supply mix and attitude towards energy production and consumption. The statistical data reflects yet no changes in the energy policies in regard to the position of nuclear power. However, in the next several years possible changes can be observed through statistical data, because the planning, the construction and possible phase out of nuclear power requires several years. Finally, the thesis reveals that the implementation of a soft energy path requires profound changes in the consumer behaviour. As several studies indicate, a soft energy path is technological and economically feasible for the Federal Republic of Germany and Canada, its implementation remains to be a political decision.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

Rapid urbanisation in China has resulted in great demands for energy, resources and pressure on the environment. The progress in China's development is considered in the context of energy efficiency in the built environment, including policy, technology and implementation. The key research challenges and opportunities are identified for delivering a low carbon built environment. The barriers include the existing traditional sequential design process, the lack of integrated approaches, and insufficient socio-technical knowledge. A proposed conceptual systemic model of an integrated approach identifies research opportunities. The organisation of research activities should be initiated, operated, and managed in a collaborative way among policy makers, professionals, researchers and stakeholders. More emphasis is needed on integrating social, economic and environmental impacts in the short, medium and long terms. An ideal opportunity exists for China to develop its own expertise, not merely in a technical sense but in terms of vision and intellectual leadership in order to flourish in global collaborations.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

The domestic (residential) sector accounts for 30% of the world’s energy consumption hence plays a substantial role in energy management and CO2 emissions reduction efforts. Energy models have been generally developed to mitigate the impact of climate change and for the sustainable management and planning of energy resources. Although there are different models and model categories, they are generally categorised into top down and bottom up. Significantly, top down models are based on aggregated data while bottom up models are based on disaggregated data. These approaches create fundamental differences which have been the centre of debate since the 1970’s. These differences have led to noticeable discrepancies in results which have led to authors arguing that the models are of a more complementary than a substituting nature. As a result developing methods suggest that there is the need to integrate either the two models (bottom up − top down) or aspects that combine two bottom up models or an upgrade of top down models to compensate for the documented limitations. Diverse schools of thought argue in favour of these integrations – currently known as hybrid models. In this paper complexities of identifying country specific and/or generic domestic energy models and their applications in different countries have been critically reviewed. Predominantly from the review it is evident that most of these methods have been adapted and used in the ‘western world’ with practically no such applications in Africa.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

Renewable energy resources, especially wind power, are expected to provide a considerable portion of the world energy requirements in the near future. Large-scale wind power penetration impacts the electricity industry in many aspects and raises a number of technical challenges for the electricity network. A day-ahead network-constrained market clearing formulation is proposed which considers demand side resources. The proposed approach can provide flexible load profile and reduce the need for ramp up/down services by the conventional generators. This method can potentially facilitate a large penetration of wind power by shifting the wind power generation from the off-peak periods to the high-peak hours. The validity of the proposed approach has been verified using the IEEE 30 bus and 57 bus test systems.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

This paper investigates the energy performance of three medium-sized healthcare buildings in Victoria, Australia, that operate only during the daytime. The aim is to provide preliminary understanding of energy consumption in this particular typology in Australia in relation to the available benchmarks. This paper also identifies the differences of energy consumption between different functional areas within medium health facilities. Building features and operational characteristics contributing to the variations in healthcare energy performance are discussed. The total annual energy consumption data ranging from 167-306 kWh/m(2) or 42-72 kWh/m(3) were compared against international data from various climatic zones. Some of the drivers of energy consumption were determined and potentials for energy and water conservation were identified. Comparison with international standards shows a possibility to achieve lower energy consumption in Victorian healthcare buildings.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

Foi avaliado o desempenho energético da suinocultura integrada à produção de milho em grão em sistema de plantio direto mecanizado. Nesta concepção de integração proposta, os dejetos suínos são utilizados como fertilizantes na produção de milho. O sistema foi delimitado envolvendo as atividades associadas ao manejo dos suínos e de produção do milho (manejo do solo, cultivo e colheita). O período de análise considerado foi de um ano, o que possibilita a produção de três lotes de suínos e duas safras de milho. Para avaliar o desempenho energético, foram criados três indicadores: eficiência energética, eficiência de uso de fontes não renováveis e o custo de energia não renovável para a produção de proteína. As entradas energéticas são compostas pelos insumos e pela infraestrutura, utilizados na criação dos suínos e na produção de milho, e pela radiação solar incidente no agrossistema. Já as saídas são representadas pelos seus produtos (suínos terminados e o milho). Os resultados obtidos nas simulações apontam que a integração melhora o desempenho energético das granjas suinícolas, aumentando a eficiência energética (186%) e a eficiência não renovável (352%), além de reduzir o custo de energia não renovável para a produção de proteína (‑58%).

Relevância:

70.00% 70.00%

Publicador:

Resumo:

This paper presents a new methodology for the operation and control of a single-phase current-source (CS) Boost Inverter, considering that the conventional CS boost inverter has a right-half-plane (RHP) zero in its control-to-output transfer function, and this RHP zero causes the known non-minimum-phase effects. In this context, a special design with low boost inductance and a multi-loop control is developed in order to assure stable and very fast dynamics. Furthermore, the proposed inverter presents output voltage with very low total harmonic distortion (THD), reduced components and high power density. Therefore, this paper presents the inverter operation, the proposed control technique, the main simulation results and a prototype in order to demonstrate the feasibility of the proposal. © 2011 IEEE.