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Contemporary state of renewable electricity in Poland depends on the following facts: (1) installed capacity in existing power plants exceeds the electrical energy consumption, necessity in pollution limitation according to EU regulations needs exchange old power plants with new electrical energy sources, (2) according to J. Biedrzycki et al. (2003) installed capacity per capita in 2001 equal to 0...
In power system operation, maintaining power flow solvability is important. In the recent deregulated environment, uncertainty has become more prevalent in power systems because of diverse power transactions and benefit-based operational schemes. Thus, in the present and future power industry, there may be more unsolvable cases than there were in the past integrated power industry. This paper presents...
In a tender for wind farm concession, energy prices must be determined by the bidding company to ensure wind energy project profitability. In a two-tariff structure tender, an energy storage system associated to the studied wind farm may, in some cases, presents an added value to the project by increasing its benefits while maintaining the same proposed energy prices. The project benefits are calculated...
This paper describes an approach for the optimal power flow (OPF) problem when reactive power supply is priced at marginal cost. This method computes the reactive power and voltage schedules minimizing the total reactive power cost. This allows obtaining curves of needs that would be the beginning for assigning the value of the reactive power generation in a deregulated power market. At the same time,...
Load serving entities (LSE) providing electricity service at regulated prices in restructured electricity markets, face price and quantity risk. We address the hedging problem of such a risk averse LSE. Exploiting the correlation between consumption quantities and spot prices, we developed an optimal, zero-cost hedging function characterized by payoff as function of spot price. We then show how such...
The paper describes a multi-stage approach that includes: determination of dynamics of the minimum offer prices, that provide loss-free operation and expansion of generation companies; simulation of competition among these companies in the regional energy markets; consideration for a corrective effect the electricity price may have on demand. The calculation results of the long-term price dynamics...
This paper introduces a method for forecasting energy prices using artificial intelligence methods such as neural networks and fuzzy logic and a combination of the two. The forecasted price is then used to design an optimal bidding strategy for a generator according to his/her degree of risk aversion. A typical thermal plant is assumed to be located in the Ontario electricity system to apply this...
The purely economic approach world-wide followed by electric market actors in the recent years led to a significant increase of cross border power trades. But nowadays, after the entry into force of the Kyoto protocol, it is possible that new environmental obligations concerning the emission of greenhouse gases (GHG) could partially modify this approach. Two main impacts on the electric sector could...
This paper is concerned with the unit commitment of hydro generating units on an hourly basis throughout a single day. The performance criterion to be optimized includes the efficiency of hydro conversion, which depends on variations in tailrace elevation, penstock head losses and turbine-generator efficiency, as well as the cost of startup/shutdown of the hydro generating units. The paper presents...
We present an applied mathematical model with stochastic input data for mean-risk optimization of electricity portfolios containing electricity futures as well as several components to satisfy a stochastic electricity demand: electricity spot market, two different types of supply contracts offered by a large power producer, and a combined heat and power production facility with limited capacity. Stochasticity...
A combined flow-based and a marginal cost approach for identifying and quantifying costs-benefits for distributed generators is presented in this paper. The proposed methodology quantifies the interconnection benefits from a distributed generator in terms of total avoided costs. A fuel cell distributed generator is considered for the analysis and for describing the methodology. The transfer distribution...
The paper deals with the automatic procedures used for the definition of voltage profiles to be adopted in the operation of bulk power systems with the aim of optimizing both the economic and security issues. After reviewing the most important automatic algorithms for optimal reactive power flow (ORPF) existing in the technical literature, some new ORPF procedures are proposed. They are based on modern...
The aim of this paper is to prove that fault levels may have a significant impact on the economic operation of modern power systems. First, we present a simple method for the incorporation of fault level constraints in the optimal power flow (OPF), the main optimization tool for the economic operation of power systems. The constraints imposed by fault levels are converted to simple non-linear (inequality)...
Nowadays it is essential for an electricity market player to have not only tools for price forecasting, but also methods for quantifying the accuracy of such forecasts, in order to perform an optimum risk management of his physical/financial portfolio. This paper proposes a simple method to assess the accuracy of electricity price forecasts, based on the probability distributions of the main factors...
In a power system with many fast and/or large changes in the generation or the consumption, for example in a system with large amounts of wind power, the frequency control is more complicated to handle efficiently. Minimizing regulation costs for the system operator in such a system requires the possibility to simulate the frequency control, but the existing methods for calculations are neither efficient...
The paper starts with an overview of 2003 blackouts in the US, Sweden/Denmark and Italy in order to analyse common threads and lessons to be learnt. The blackouts have exposed a number of challenges facing utilities worldwide. Increased liberalisation of electricity supply industry has resulted in a significant increase in inter-area (or cross-border) trades which often are not properly accounted...
This article presents a methodology to remunerate the ancillary services of generation reserve and reactive power support as function of the benefit provided by the generators to the power system. The benefit provided by the ancillary service of generation reserve is calculated based on the reduction in the expected energy not supplied, multiplied by the unitary interruption cost of the power supply...
Two years after the Economic Committee of the Polish Government approved the electricity market structure, the Balancing Market began its operation, on the Is' of September 2001, using the day ahead, one-hour interval balancing mechanism. The assumed structure, trade and balancing rules of the Polish Electricity Market, makes it one of the most advanced electricity markets in Europe. Despite many...
Customer classification is aimed at providing to the electricity suppliers a sound information on the electricity consumption, to be used for formulating dedicated tariff structures. Different clustering methods can be adopted for assisting the process of electricity customer classification. Previous studies have identified two methods - hierarchical clustering and follow-the-leader - as most promising...
Voltage control and reactive power management are usually studied and applied mainly by the technical point of view. System operators and planners have developed complex control schemes, in order to achieve a secure and efficient operation. However, the deregulation of the electric systems requires the definition of market procedures ensuring an effective management of reactive resources on which...
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