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Today's power utilities, around the world, own multiple substations that are connected together to form a complex energy network. The functions within and between these substations are being automated according to globally accepted power utility automation standard IEC 61850. This automation results in efficient operation and enhanced protection of power network with the aid of the communication system. Implementing the protection schemes modeled using communication configurations of standardized information exchange will lead to digital power grid. Designing an IEC-61850-based protection scheme to take care of the faults outside the substations is a challenge, as the typical local-area-network-based generic-object-oriented substation events and sampled-value messages need to be transmitted over a wide-area network. This paper presents communication configuration for line current differential protection schemes applied between two automated substations. It presents the simulation results of communication configuration network between two substations. Its performance is evaluated using a network simulator tool. This study intends to guide the development of a robust protection scheme with IEC-61850-based communication configuration. [ABSTRACT FROM PUBLISHER]

This paper proposes a new framework in calculating the ex post prices for the spot electricity market. The proposed method finds a set of prices that are as consistent as possible with the actual outputs of resources correctly following their dispatch instructions. Two alternative consistency metrics are proposed in the paper. One measures the difference between the actual performance of an individual resource and its bid-based profit-maximizing response to the ex post prices in a perfectly competitive market. Another measures the difference between the ex post price and the price that supports the actual response of an individual resource. Compared to the existing approaches adopted in the real-time electricity markets in the U.S., the proposed method solves the ex post energy and ancillary service prices directly and simultaneously. It does not require heuristics that are hard to justify, and has a much clear definition for the pricing problem than the existing approaches do. Moreover, the proposed approach is flexible in the price control required by the market operators. Numerical examples are presented to further demonstrate the validity of this approach. [ABSTRACT FROM AUTHOR]

In a power system covering a large geographical area, a single model for load forecasting of the entire area sometimes cannot guarantee satisfactory forecasting accuracy. One of the major reasons is because of the load diversity, usually caused by weather diversity, throughout the area. Multiregion load forecasting will be a feasible and effective solution to generate more accurate forecasting results, as well as provide regional forecasts for the utilities. However, a major challenge is how to optimally partition/merge the areas according to the regional load and weather conditions. This paper investigates the electricity demand and weather data from an electric utility in Midwest, U.S. Based on the data analysis, we demonstrate the existence of weather and load diversity within its control area and then develop a short-term multiregion load forecasting system based on support vector regression for day-ahead operation and market. The proposed multiregion forecasting system can find the optimal region partition under diverse weather and load conditions and finally achieve more accurate forecasts for aggregated system load. The proposed forecasting system has been tested by using the real data from the system. The numerical results obtained for different region partition schemes validate the effectiveness of the proposed multiregion forecasting system. The detailed discussions on the forecasting results have also been given in this paper. [ABSTRACT FROM AUTHOR]

Short-term load forecasting is always a popular topic in the electric power industry because of its essentiality in energy system planning and operation. In the deregulated power system, an improvement of a few percentages in the prediction accuracy would bring benefits worth of millions of dollars, which makes load forecasting become more important than ever before. This paper focuses on the short-term load forecasting for a power system in the U.S., where several alternative meteorological forecasts are available from different commercial weather services. To effectively take advantage of the alternative meteorological predictions in the load forecasting system, a new comprehensive forecasting methodology has been proposed in this paper. Specifically, combining forecasting using adaptive coefficients is applied to share the strength of the different temperature forecasts in the first stage, and then, ensemble neural networks have been used to improve the model's generalization performance based on bagging. The proposed load forecasting system has been verified by using the real data from the utility. A range of comparisons with different forecasting models have been conducted. The forecasting results demonstrate the superiority of the proposed methodology. [ABSTRACT FROM AUTHOR]

FERC Order 755 requires each RTO/ISO to use market-based mechanisms to select and compensate frequency regulation resources based on a two-part payment methodology, i.e., a capacity payment to keep the capacity in reserve and a performance payment to reflect the amount of work each resource performs in real-time in response to the system operator's dispatch signal. This paper discusses how MISO enhanced its market rules to implement a market-based regulation performance payment. The market enhancement includes four key areas: quantifying the movement of regulation, modifications to the market clearing processes, performance accuracy measurement, and performance-based two-part regulation compensation. [ABSTRACT FROM PUBLISHER]

The use of alternate fuels and raw materials in the cement manufacturing process has evolved substantially over the last two to three decades, along with approaches to acquire regulatory approval. Most recently, the Environmental Protection Agency (EPA) has published new regulations as an overlay to what has been in place, having the potential to significantly impact this practice. Instead of dealing with the state agencies that usually have permitting authority, the new rules add another layer of regulatory hurdles by EPA. The new regulations also force a more significant overlap of the air permitting and solid waste rules. As a result, implementing an alternate material program and seeking approval has the potential to be considerably more challenging for the regulated community, in addition to adding complexity for the state agency permitting staff. This paper provides an update on the latest solid waste and air regulations applicable to alternative material use in cement plants, and potential implications for the U.S. industry. Early experiences will be explored, in addition to contemplating potential permitting and/or approval pathways expected to be encountered with the newest regulations in place. [ABSTRACT FROM AUTHOR]

Energy storage is a natural option toward adding the much-needed flexibility for integrating higher amounts of wind generation into the existing power system. This paper presents field results and analyses quantifying the ability and the value of Sodium Sulfur (NAS) battery energy storage toward shifting wind generation from off-peak to on-peak, limiting the ramp rate of wind farm output, and a strategy to integrate the aforementioned goals. The battery can also be considered on a system level independent of wind. It is argued that even in its capacity as a system resource independent of wind, the battery can aid integration of wind generation. Analyses quantifying the value of the battery in the energy and operating reserve markets are presented. Financially optimal locations to site the battery have also been identified. The presented research is a part of the “Wind to Battery” project led by Xcel Energy, a major U.S. utility. [ABSTRACT FROM PUBLISHER]

This paper focuses on the energy storage system and the power electronic interface included in microsources of the CERTS microgrid. CERTS stands for the Consortium for Electric Reliability Technology Solutions. The consortium was formed in 1999 to research, develop, and disseminate new methods, tools, and technologies to protect and enhance the reliability of the U.S. electric power system and efficiency of competitive electricity markets. To provide the plug-and-play feature and the power quality requirements of the CERTS microgrid, all microsources regardless of their prime mover type must have a unified dynamic performance. This necessitates attaching an energy storage module to some or all of the microsources. The storage module is attached to the prime mover through a power electronic interface that couples the microsource to the microgrid. Details of the energy storage module, the power electronic interface and the corresponding controls are described. Performance of an example microsource, which includes a synchronous generator, a storage module and an electronic interface, is studied. Dynamic performance of the example microsource when operating in the CERTS microgrid is evaluated based on digital time-domain simulations in the EMTP-RV software environment. Effectiveness of the storage module, the electronic interface and the corresponding controls in enhancing the microsource performance is verified. [ABSTRACT FROM AUTHOR]

This paper proposes a practical and effective model for the generation forecasting of a wind farm with an emphasis on its scheduling and trading in a wholesale electricity market. A novel forecasting model is developed based on indepth investigations of meteorological information. This model adopts a two-stage hybrid network with Bayesian clustering by dynamics and support vector regression. The proposed structure is robust with different input data types and can deal with the nonstationarity of wind speed and generation series well. Once the network is trained, we can straightforward predict the 48-h ahead wind power generation. To demonstrate the effectiveness, the model is applied and tested on a 74-MW wind farm located in the southwest Oklahoma of the United States. [ABSTRACT FROM AUTHOR]

Ancillary service markets are a very important part of the Standard Market Design and are under development or implementation on a centralized basis in major U.S. electricity markets. This paper presents the market clearing framework for the co-optimized real-time energy-reserve market that has been developed and implemented in the ISO New England (ISO NE). In this co-optimized market clearing model, reserve, products are procured on a zonal basis to satisfy the first and the second contingency protection criteria required by the ISO NE's real-time operations for both the entire area and typical import-constrained areas. The proposed zonal reserve model is derived from simulating each contingency event in the predefined reserve zones. Differing from standard industrial practices, the proposed zonal reserve model recognizes reserve deliverability for nested reserve zones and allocates the zonal total transfer capability between energy and reserves in an economic way. Numerical examples for a two-zone system are presented to demonstrate the validity of this modeling technique. [ABSTRACT FROM AUTHOR]

This paper presents the validation of a numerical model based on the full-scale broken insulator tests on a 138-kV high-voltage steel transmission line. The University of Wisconsin and the Electric Power Research Institute performed these tests in 1978. A finite-element model of the line is developed to perform incremental nonlinear dynamic analysis, carried out in the time domain. Upon validation of the numerical model with the test results, a sensitivity study is carried out for various insulator lengths, ice thicknesses, and initial tensions to determine the effects of these parameters on the impact loads on the tower cross arm. Results of the study show that the impact loads are less sensitive to the change in insulator length but they do vary significantly when the ice loads and the initial tensions are increased. Studies of this type are now possible and are cost effective because of the use of commercial software not available at the time of the original research. [ABSTRACT FROM AUTHOR]

On August 14, 2003, the U.S. faced the largest blackout in history, which left over 50 million people without electricity in eight U.S. states and part of Canada. This paper investigates the effects of the blackout on the security values of the U.S. electric utilities and manufacturing firms in the electric power equipment industry, using an event study method. The results of this empirical study show that the electric utilities were negatively affected, but the electrical equipment manufacturing firms were significantly, positively affected. [ABSTRACT FROM AUTHOR]

Natural gas fired power plants (NGFPP) are important electricity generation resources in the United States. Optimizing the natural gas supply portfolio, especially the short-term portfolio, is critical for the day-to-day operations and the financial performance of NGFPPs. Traditionally, such optimization problems are solved using cost-minimization-based frameworks. However, such frameworks are facing challenges due to the lack of consideration of associated financial risks in the current deregulated electricity markets, which the electric utility companies (EUCs) who own and operate NGFPPs now bear. This paper presents a utility-maximization-based framework to optimize the short-term natural gas supply portfolio for the EUC. It considers the financial risks associated with the portfolio and incorporates the risk preferences of the EUCs as decision-maker (DM) in the portfolio optimization process. An application of the proposed framework is provided, and its results show that the proposed framework is more desirable in terms of risk-cost trade-off optimization. [ABSTRACT FROM AUTHOR]

In a competitive electricity market, a generation company (Genco) can manage its trading risk through trading electricity among multiple markets such as spot markets and contract markets. The question is how to decide the trading proportion of each market in order to maximize the Genco's profit and minimize the associated risk. Based on the mean-variance portfolio theory, this paper proposes a sequential optimization approach to electric energy allocation between spot and contract markets, taking into consideration the risks of electricity price, congestion charge, and fuel price. Especially, the impact of the fuel market on electric energy allocation is analyzed and simulated with historical data in respect of the electricity market and other fuel markets in the U.S. Simulation results confirm that the proposed analytic approach is consistent with intuition and therefore reasonable and feasible for a Genco to make a trading plan involving risks in an electricity market. [ABSTRACT FROM AUTHOR]

The market uncertainties in the generation business in the U.S. electric power industry have increased the significance of two factors in generation planning: financial risks and managerial flexibilities. At the same time, numerous utilities have multiple generation planning: projects that are interrelated with respect to their market values. For such utilities, in order to quantitatively address these two factors, in this paper, we develop and analyze a real options model for general n interrelated projects. Specifically, first, we derive a unique lattice process that approximates interrelated continuous processes for the evolution of values of projects and options (e.g., selling a constructed project). The steps of the approximation for n projects are presented progressively starting from two projects. Next, based on the lattice process, we investigate the impact of interrelation on the values of options. Then, we provide a backward dynamic programming model for optimal sequential decision making where the decisions are made over the options. Finally, managerial insights and economic implications are illustrated via numerical examples. [ABSTRACT FROM AUTHOR]

Utilities have long struggled with establishing re- source planning criteria that ensure adequate resources to meet loads at low cost. Historically, many utilities used planning reserve margin criteria. The onset of deregulation brought about a paradigm shift in which it was expected that markets would provide a more efficient mechanism for maintaining resource sufficiency in the course of system demand growth. Major power shortages in the Midwest and California in the wake of deregulation led to a reexamination by most regions of the need for centralized resource planning and integrated resource plans. Reserve margin techniques continue to be used by many resource planners to ensure resource adequacy. Simulation-based probabilistic assessments can provide a more direct measure of adequacy but are quite intensive computationally and therefore only allow exploring a limited number of scenarios. In this paper, we suggest a simple analytical probabilistic approach to maintaining resource adequacy and calculating peak load carrying capability of incremental generating units. The methodology targets a level of system adequacy, rather than a specified reserve margin, under system expansion. It provides. a powerful technique for simply calculating probability-based load carrying capability of resource additions without iteratively running computationally intensive stochastic computer models. The technique also provides a simple but effective method for developing portfolios of resources with comparable contributions to system adequacy. The latter may be employed in capacity expansion algorithms as a simpler, more efficient, and more accurate method of determining least-cost resource additions than targeting planning reserve margins. Applications of these techniques to the IEEE Reliability Test System illustrate the methods and verify the results with a stochastic model. [ABSTRACT FROM AUTHOR]

Research into transmission pricing and congestion management in interconnected power systems, such as those found in USA and Europe, requires an appropriate benchmark system to test different methodologies. Creation of a realistic benchmark system is difficult as utilities are often unwilling to disclose details of their own systems because of commercial sensitivity and security reasons. This paper presents development of an approximate model of a European interconnected system which could be used to study the effects of cross-border trades. In creating the load-flow model, only publicly available information was used. Comparison of simulation results conducted on the test system with the published cross-border flows and power transfer distribution factors showed a very good correlation, exceeding 90%. [ABSTRACT FROM AUTHOR]