Power System Economics Research Papers (original) (raw)

Coal and hydro will be the main sources of electric energy in Chile for the near future, given that natural gas from neighbouring Argentina is not longer available and LNG price projections leave it only as a backup fuel. The country has limited energy resources, importing more than 73% of its energy. Hydroelectric untapped resources are significant, but they are mostly located in the extreme south of the country, in unpopulated areas of great unspoiled beauty. Non governmental organizations both within the country and from the US are strongly opposing the use of these resources. Renewables, which are only at an early stage, are argued as an alternative, but do not represent a solution with rates of growth of electricity demand over 6% a year. This summary discusses the issues being faced and the environmental dilemma faced by the country, where both coal and hydro produce some kind of impact. The role of the State and the private sector in determining the country's energy matrix arises as another central discussion ⋅ .

- by
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- Energy Policy, Power System Economics, Natural Gas, Power Generation

Electricity tariff setting is a primary instrument of economic regulation. Tariff provides economic signals, which determine the volume and nature of the demand and supply of power. It is not surprising therefore that a considerable portion of the power sector reform effort is expended on rationalizing tariffs. Through this paper we aim to discuss the potential for alternative ways of charging for electricity and providing concessions to improve the affordability of essential electricity use, facilitate the equitable, efficient and full recovery of the cost of supplying electricity and provide clear information to consumers regarding the impact of their electricity use. Many of the existing tariff elements have been formulated over the years as a result of available technology. In reviewing the electricity tariff structures it is therefore important to consider some of the developments in technology particularly with respect to metering which may facilitate a greater variety in tariff structures now or in the future.

- by Jitendra Rai
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- Electrical Engineering, Renewable Energy, Energy, Power System Economics

Marginal cost pricing is widely recognized as the core of any sound approach to economic valuation of transmission services. This paper presents results that help to recognize and to compute the several components of the spot prices, so... more

- by Ignacio Pérez-ariaga
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- Power System, Power System Economics, Economic valuation

HISTORICAL crossroads. Decisions must soon be made about the direction of grid development so that it can meet extraordinary economic challenges, critical needs for energy security, and essential requirements for a sustainable way of life. This is a defi ning moment in terms of our nation's commitment to providing an electric energy system, including a bulk transmission network, that can meet the societal needs of the 21st century and beyond. A major evolutionary step in the grid's design, planning, and operation is needed, one that adopts new design concepts and innovative technologies that can be integrated into a modern infrastructure. The American Recovery and Reinvestment Act of 2009 (ARRA) provided a number of opportunities to achieve these far-reaching objectives. This article describes a vision of-and the steps needed to reach-the national objective of having a smart grid infrastructure. Our focus is on new concepts and related technological considerations in developing smart grid solutions that will meet the seven objectives of the smart grid, as identifi ed by the U.S. Department of Energy (DOE): 1) enabling informed participation by customers 2) accommodating all generation and storage options 3) enabling new products, services, and markets 4) providing the level of power quality required to meet the full range of needs in the 21stcentury economy 5) optimizing asset utilization and operating efficiently 6) addressing disturbances through automated prevention, containment, and restoration 7) operating resiliently against all hazards. To achieve these goals, smart research and development efforts must harmonize four principal aspects of the future grid: ✔ Expansion of the electricity grid infrastructure: This includes building new infrastructure to replace aging infrastructure while expanding grid capacity, improving the operation and efficiency of the existing infrastructure, and developing novel concepts, technologies, and applications. The smart grid will integrate renewable generation and distributed energy sources. It will also enable creative options for customers to participate in system operations by offering their loads and storage capability (e.g., from plugin hybrid electric vehicles) as resources. Customers also want options for making their own usage more energy and cost efficient (such as through building energy management systems).

This paper describes the optimal power flow (OPF) architecture implemented in MATPOWER, an open-source Matlab power system simulation package. It utilizes an extensible architecture that allows the user to easily add new variables, constraints and costs to the standard OPF problem formulation while preserving the structure needed to use pre-compiled solvers. A software object is used to encapsulate the definition of the problem formulation, manage the corresponding named sets of variables, constraints and costs, and handle all of the tedious index maintenance tasks. The software design has the advantage of minimizing the coupling between variables, constraints and costs, making it possible, for example, to add variables to an existing model without having to explicitly modify existing constraints or costs to accommodate them. The example of adding joint co-optimization of reserves to the OPF, based on fixed zonal reserve requirements, is used to illustrate the capabilities of MATPOWER's extensible OPF architecture.

- by Ray Zimmerman
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- Computer Architecture, Software Engineering, Power Systems, Software Maintenance

Ancillary Services are essential to the reliability and security of power system operation in any competitive electricity market environment. Procurement of ancillary services must take into account effective use of the capacity under emergency conditions, delivery time, transmission limitations, and local area requirements. Regional procurement of ancillary services is an approach that results in effective distribution of reserves and ensures continuous reliability in the event of a contingency occurring anywhere in the system. However, most ISOs procure and price ancillary services based on the least-cost service with little regard to zonal dispersion. In general, such an approach is not sufficient to ensure continuous reliability and security of the power system This paper presents a new methodology and numerical examples for procuring and pricing ancillary services on a regional basis, with an explicit representation of imports in a simultaneous energy/reserve market environment.

- by Ziad Alaywan
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- Power System, Power System Economics, Power System Operation, Optimal Power Flow
- by Mohammad Iqbal As'ad Mauludy
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- Business, Economics, Capitalism, Power System Economics

MATPOWER is an open-source Matlab-based power system simulation package that provides a high-level set of power flow, optimal power flow (OPF), and other tools targeted toward researchers, educators, and students. The OPF architecture is designed to be extensible, making it easy to add user-defined variables, costs, and constraints to the standard OPF problem. This paper presents the details of the network modeling and problem formulations used by MATPOWER, including its extensible OPF architecture. This structure is used internally to implement several extensions to the standard OPF problem, including piece-wise linear cost functions, dispatchable loads, generator capability curves, and branch angle difference limits. Simulation results are presented for a number of test cases comparing the performance of several available OPF solvers and demonstrating MATPOWER's ability to solve large-scale AC and DC OPF problems.

- by Carlos E Murillo-Sanchez
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- Engineering Education, Power System, Power System Economics, Open Source

Improved and controlled power quality is one of the essential and fundamental need in any power driven industry for optimum utilization of resources. However critical problems in power quality have been recognized such as sags, swells, harmonic distortions and other interruptions. Out of these sags and swells are predominantly found and have severe impact on the electrical devices or electrical machines and therefore needs to be compensated at an earliest to ensure any mal-operation or failure. To crack these problems custom power devices are used like unified power-quality conditioner (UPQC), distribution-STATCOM (DSTATCOM) and dynamic voltage restorer (DVR). The DVR is a one of the custom power device used for the compensation of voltage sag and swell with an advantage of active/reactive power control. A major volume of literature reported in past several years on different configurations of DVR and different control technique used in it. In context of this a detailed review on DVR has been presented with different possible power circuit topologies and control techniques available to reconcile these power quality issues. This review article will contribute in better selection of control strategy and power circuit for optimum performance of DVR for a particular requirement. Also it presents a very helpful investigation for the researcher in this field.

This article gives the complete information about the Reactive Power compensation given to the distribution system for reducing the Power Losses. In this article, a case study of MPPKVVCL, Jabalpur, India substation of 8MVA at 33/.4 kV data is taken with shunt capacitor bank and without shunt capacitor bank at peak hours is consider. It is seen from load curve that with the switch in of shunt capacitor bank, current of about
10- 12 Ampere is dropped in 11 kV line. This drop of current reduces the burden on the devices of the 11 kV feeder. Also current saved is used for other customers for providing Electrical Power. Further MATLAB simulation is done to show the current drop in 11 kV feeder line with the inclusion of shunt capacitor bank. Also, Annuity is used for Economic analysis for understanding the lifecycle cost saving with the inclusion of shunt capacitor bank is calculated. Nonetheless, this methodology can be used for any configuration knowing the actual saving with the inclusion of shunt capacitor in the distribution system.

- by Athanasios Rizakis
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- Social Networks, Cultural Heritage, Political Elites, Power System Economics

Energy storage components improve the energy efficiency of systems by reducing the mismatch between supply and demand. For this purpose, phase change materials are particularly attractive since they provide a high energy storage density at a constant temperature which corresponds to the phase transition temperature of the material. Nevertheless, the incorporation of phase change materials (PCM) in a particular application calls for an analysis that will enable the researcher to optimize performances of systems. Due to the non-linear nature of the problem, numerical analysis is generally required to obtain appropriate solutions for the thermal behavior of systems. Therefore, a large amount of research has been carried out on PCMs behavior predictions. The review will present models based on the first law and on the second law of thermodynamics.

- by Nizar Ben salah and +2
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- Engineering, Numerical Analysis, Sustainable Energy, Power System Economics

A detailed AC OPF-based formulation for procuring, pricing, and settling energy and ancillary service in simultaneous auctions by integrated market systems is presented. The paper provides clear definitions of Locational Marginal Prices for energy and Ancillary Service Marginal Prices in terms of Lagrange multipliers. The characteristics of the prices are analyzed especially when economic substitution among ancillary services is required. The paper also evaluates the conditions under which opportunity costs are incurred to units that provide ancillary services. It is particularly shown that the intuitive belief that the provision of regulation down service does not incur opportunity cost to the provider, in general, is not true.

- by Ziad Alaywan
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- Power System Economics, Optimal Power Flow, Opportunity Cost, Lagrange Multiplier

The article estimates the costs of plug-in electric vehicles (EVs) in a future power system as well as the benefits from smart charging and discharging EVs (smart EVs). To arrive in a good estimate, a generation planning model was used to create power plant portfolios, which were operated in a more detailed unit commitment and dispatch model. In both models the charging and discharging of EVs is optimised together with the rest of the power system. Neither the system cost nor the market price of electricity for EVs turned out to be high (36e263 V/vehicle/year in the analysed scenarios). Most of the benefits of smart EVs come from smart timing of charging although benefits are also accrued from provision of reserves and lower power plant portfolio cost. The benefits of smart EVs are 227 V/vehicle/year. This amount has to cover all expenses related to enabling smart EVs and need to be divided between different actors. Additional benefits could come from the avoidance of grid related costs of immediate charging, but these were not part of the analysis.

- by Juha Kiviluoma
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- Mechanical Engineering, Energy, Power System, Modeling

- by Rajesh Garai and +1
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- Power System Economics, Matlab, India, Smart Metering

The general design for the real-time electricity market presented in this paper optimizes and prices both real and reactive power simultaneously in an AC setting, where all assets-generation, load and transmission-are allowed to bid and are financially settled at the locational price times energy consumed or produced. The result is that transmission lines are compensated for both capacity and admittance, providing incentives for efficient operation of transmission-related assets such as FACTS devices, if price-taking behavior is assumed. Losses are incorporated into the design and become an operating cost for transmission. The market design is shown to be revenue neutral and, under some assumptions, nonconfiscatory.

- by Ross Baldick
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- Market Design, Power System Economics, Applied Economics, Regulatory Economics

The implementation of auctions of long-term firm energy call options and forward contracts as part of the instruments adopted in emerging countries to ensure resource adequacy is discussed. These mechanisms are being implemented in Latin American nations (Brazil, Chile, Peru, El Salvador & Panama) and fast-growing economies in Europe such as Turkey. Brazil has led this process and in overall has auctioned about 25,000 average MW of contracts, involving about 65 billion USD in financial transactions, while Chile has carried out its first auction in 2006, involving about 1,300 average MW (30% of energy sales of the main interconnected Chilean system expected for 2010). Overall, this mechanism is proving to be adequate to attract investments and ensure resource adequacy.

- by Bernardo Bezerra
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- Peru, El Salvador, Power System Economics, Investments

- by Ray Zimmerman
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- Engineering Education, Power System, Power System Economics, Open Source

A new method for distribution access via uniform pricing for the remuneration of distribution networks is presented. The proposed approach merges in a unified framework the investments, the optimal network operation requirements, the effect of the price elasticity of demand, and the application of hourly pricing for demand side management purposes. Hourly uniform marginal prices-understood as tariffs of use of the network-are obtained from maximum social welfare condition sending efficient signals to the utility and consumers, related to the optimal operation of the grid and use of the energy at peak and valley hours. This method is used in the context of a Performance Based Ratemaking regulation to get model companies from operational optimized real networks. Capital fees are integrated in the marginal tariff of use, by means of the New Replacement Value concept, broadly used in yardstick competition. The model is stated as a mixed-integer linear optimization problem suitable to be solved through well-known linear programming tools. The methodology has been successfully tested in a 42-bus test distribution network.

- by Alberto Urdaneta and +2
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- Power System Economics, Demand Side Management, Price Elasticity, Social Welfare

the objective of this work is to discuss the modeling of auctions of long-term electricity supply contracts for new capacity in Brazil. The modeling of risks such as price-quantity (hydrological) risk, project completion risk, environmental constraints, climate change and regulatory risks are discussed. An analytical model will be developed to price these risks and case studies will be presented for real projects that have participated in the Brazilian contract auctions for new capacity. We also discuss selection of projects with different risks.

- by Bernardo Bezerra
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- Climate Change, Power System Economics, Electricity Market, Auction Theory

This paper presents a methodology to improve the power system economical dispatch from a voltage stability margin perspective. The time horizon under discussion is the short-term operation planning. The proposed method is based on active/reactive power re-dispatch for normal operation, and also minimum load shedding strategies in case of critical contingencies. The actions are taken in the direction provided by modal participation factors computed for generator and load buses. The generators with negative impact on system margin, which are indicated by the modal index, are penalized with high costs on the objective function of the optimal power flow program used to run the re-dispatch process. Results of this work show a decrease on system losses and significant increase on voltage stability margin as well as on system reactive reserves. In addition, this work presents a study considering critical contingencies, for which is proposed an optimal load shedding strategy also based on modal participation factors to identify the most adequate buses for load shedding purposes. Finally, the proposed methodology is applied considering a typical hour-to-hour daily load curve, and the method presented very good performance since it considerably increases voltage stability margin for the insecure intervals.

- by SECUNDINO SOARES
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- Power System, Power System Economics, Reactive Power, Voltage Stability

Modern operation of power systems is based with priority and on economical aspects. The most efficient operation of a power system is based on the unit commitment and economic dispatch concepts, which are governed by well established economical criteria. This seemingly simple approach is not always possible for various reasons, e.g. in the case of autonomous power systems (APS) usually located in small-medium size islands. In reality, the aim of an APS is to cover the hourly electrical demand, while is taking into account the maintenance of the involved generating units, so they are available in appropriate time periods. Usually, a specific operating policy is followed, which determines the way the generating units should be loaded, depending on the structure of the network involved. For the proper operation of an APS a method is developed, in this work, which generally is based on such a policy of APS operation and in addition attempts to make a compromise between economic and maintenance constraints. The proposed method is applied successfully to an APS of a medium size Hellenic island.

Through looking back to the transformative processes of the past 25 years, this study outlines the determining characteristics of the current international power relations, predominantly with an analytical approach. It seeks to answer the following questions: how should we approach the analysis of the international system, the changes that have occurred during the past 25 years, and today’s power relations? In doing so, the author offers an overview of how international power relations have transformed from the break-up of the bipolar world order to the current multipolar setup; how the concept of power and its elements have evolved; and how the range of influential actors of the international system has broadened, in overall changing the hierarchical structure of the whole system. Finally, the study also offers an analytical picture of the most important characteristics of international relations, identifying where the stakes for Europe and the European Union currently lie, as its course of development is also the primary strategic determinant of the future of Hungary.

- by Péter Tálas
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- Power System Economics, Soft Power, Power relations, Demographics

Currently, there is a national push for a smarter electric grid, one that is more controllable and flexible. Only limited control and flexibility of electric assets is currently built into electric network optimization models. Optimal transmission switching is a low cost way to leverage grid controllability: to make better use of the existing system and meet growing demand with existing infrastructure. Such control and flexibility can be categorized as a “smart grid application” where there is a co-optimization of both generators or loads and transmission topology. In this paper we form the dual problem and examine the multi-period N-1 reliable unit commitment and transmission switching problem with integer variables fixed to their optimal values. Results including LMPs and marginal cost distributions are presented for the IEEE RTS 96 test problem. The applications of this analysis in improving the efficiency of ISO and RTO markets are discussed.

Currently, there is a national push for a smarter electric grid, one that is more controllable and flexible. The full control of transmission assets are not currently built into electric network optimization models. Optimal transmission switching is a straightforward way to leverage grid controllability: to make better use of the existing system and meet growing demand with existing infrastructure. Previous papers have shown that optimizing the network topology improves the dispatch of electrical networks. Such optimal topology dispatch can be categorized as a smart grid application where there is a cooptimization of both generators and transmission topology. In this paper we present a co-optimization formulation of the generation unit commitment and transmission switching problem while ensuring -1 reliability. We show that the optimal topology of the network can vary from hour to hour. We also show that optimizing the topology can change the optimal unit commitment schedule. This problem is large and computationally complex even for medium sized systems. We present decomposition and computational approaches to solving this problem. Results are presented for the IEEE RTS 96 test case.

- by Michael Ferris and +1
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- Power Systems, Integer Programming, Power System Economics, Switching

The main objective of this paper is to present the preliminary results obtained within the SUSPLAN EU Project 2 , regarding the integration of increasing levels of Renewable Energy Sources (RES) into the future Spanish energy system. Firstly, the optimal expansion of the Spanish electricity generation capacity from 2020 to 2050 is determined for four different storylines. Then, for each one of these storylines, a detailed analysis of the power system operation is performed for the years of 2020 and 2050. Two electricity models are used for that purpose: i) a long term generation expansion model, and ii) a medium-term system operational model. The results obtained showed that a high amount of RES generation could be integrated into the future Spanish power system but this should be accompanied with flexible generation and storage units for ensuring a secure system operation.

- by Pablo Frias
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- Power System, Power System Economics, Energy efficiency, renewable Energy sources

The adequacy problem in electricity market is becoming a very important issue as there is neither theoretical proof nor practical evidence of correct delivering of sufficient and timely generation capacity when it is needed in a real (imperfect) environment. In contrast, classical market design seems to fail when facing high demand growth and/or large hydro share as seen in several Latin American countries such as Chile, Brazil, Colombia and Peru among others. Currently, various mechanisms have arisen across this region with the intention of stimulating energy procurement and new investment. These are mainly based on long-term contract and options obligations, which are allocated through auctions. Auction theory then becomes very important to ensure optimal allocation and efficient prices for both the new generation and the end user. However, difficulties arise when applying pure auction theory because basic hypotheses are not met by most electricity markets. The objective of this paper is to address and discuss the Latin American experience with auction design for long-term contracts focusing on practical design and theory. The different mechanisms and auctions for ensuring supply adequacy are listed along with theoretical justification as part of the potential solution for the adequacy problem that different economies have proposed.

- by Bernardo Bezerra
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- Market Design, Procurement, Peru, Power System Economics

The California ISO is in the process of migrating from a decentralized and zonal based market system to a centralized and nodal based market system. This is an effort motivated by the standard market design proposed by the U.S. federal energy regulatory commission and by the operational problems encountered by the California ISO over the past five years using a zonal-based model. This paper explains why the California ISO has decided to move from the zonal market system to a nodal market system from an operational perspective.

- by Ziad Alaywan
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- Market Design, Power System Economics, Electricity Market

This paper presents a new optimization technique based on quantum computing principles to solve a security constrained power system economic dispatch problem (SCED). The proposed technique is a population-based algorithm, which uses some quantum computing elements in coding and evolving groups of potential solutions to reach the optimum following a partially directed random approach. The SCED problem is formulated as a constrained optimization problem in a way that insures a secureeconomic system operation. Real Coded Quantum-Inspired Evolution Algorithm (RQIEA) is then applied to solve the constrained optimization formulation. Simulation results of the proposed approach are compared with those reported in literature. The outcome is very encouraging and proves that RQIEA is very applicable for solving security constrained power system economic dispatch problem (SCED).

- by khaled EL-Naggar
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- Power System Economics, State Estimation, Quantum entanglement, Economic System

It is generally believed that plug-in electric vehicles (PEVs) offer environmental and energy security advantages compared to conventional vehicles. Policies are stimulating electric transportation deployment, and PEV adoption may grow significantly. New technology and business models are being developed to organize the PEV interface and their interaction with the wider grid. This paper analyzes the PEVs' integration into a building's Energy Management System (EMS), differentiating between vehicle to macrogrid (V2M) and vehicle to microgrid (V2m) applications. This relationship is modeled by the Distributed Energy Resources Customer Adoption Model (DER-CAM), which finds optimal equipment combinations to meet microgrid requirements at minimum cost, carbon footprint, or other criteria. Results derive battery value to the building and the possibility of a contractual affiliation sharing the benefit. Under simple annual fixed payments and energy exchange agreements, vehicles are primarily used to avoid peak demand charges supplying cheaper off-peak electricity to the building during workdays.

This paper examines bidding strategies in a bilateral market in which generating companies submit bids to loads. A load accepts electricity delivery from the generator with the lowest bid at its bid price as long as this price is not higher than the load's willingness to pay. Necessary and sufficient conditions of Nash equilibrium (NE) bidding strategy are derived based on a generic generating cost matrix and the loads' willingness to pay vector. The study shows that in any NE, efficient allocation is achieved. Furthermore, all Nash equilibria are revenue equivalent for the generators. Based on the necessary and sufficient conditions, this problem is formulated as an optimal assignment problem. Network optimization techniques are applied to calculate NE bid prices for the generators.

- by Chen-ching Liu
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- Environmental Economics, Game Theory, Power System Economics, Network optimization

With the development of modern power systems, economic dispatch problem has received an increasing attention. The economic dispatch is an optimization problem to find the most economical schedule of the generating units while satisfying load demand and operational constraints. In this paper, Tabu Search is applied to economic dispatch problem. The proposed method has been demonstrated through a six-unit system. The results of the proposed method are compared with those of an Improved Hopfield NN approach (IHN) [1], a Fuzzy Logic Controlled Genetic Algorithm (FLCGA) [2], an Advance Engineered-Conditioning Genetic Approach (AECGA) [3] and an Advance Hopfield NN approach (AHNN) [4].

- by Halis Altun
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- Genetics, Tabu Search, Power System Economics, Genetic Algorithm
- by Murat Çiçek
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- European Studies, European Union, China, Chinese Politics

This paper focuses on how the ancillary service market designs are implemented and how they may require changes on systems with greater penetrations of variable renewable energy suppliers, in particular wind power. Ancillary services markets have been developed in many of the restructured power system regions throughout the world. Ancillary services include the services that support the provision of energy to support power system reliability. The ancillary services markets are tied tightly to the design of the energy market and to the physics of the system and therefore careful consideration of power system economics and engineering must be considered in their design. This paper focuses on how the ancillary service market designs are implemented and how they may require changes on systems with greater penetrations of variable renewable energy suppliers, in particular wind power.

- by Brendan Kirby
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- Renewable Energy, Wind Energy, Market Design, Power System

The general design for the real-time electricity market presented in this paper optimizes and prices both real and reactive power simultaneously in an AC setting, where all assets—generation, load and transmission—are allowed to bid and are financially settled at the locational price times energy consumed or produced. The result is that transmission lines are compensated for both capacity and admittance, providing incentives for efficient operation of transmission-related assets such as FACTS devices, if price-taking behavior is assumed. Losses are incorporated into the design and become an operating cost for transmission. The market design is shown to be revenue neutral and, under some assumptions, nonconfiscatory.

- by Emily Alvarado
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- Market Design, Power System Economics, Applied Economics, Regulatory Economics

The objective of this work is to discuss the generation options and challenges to meet an increasing electricity demand in Brazil. Emphasis will be put on the challenge of conciliating generation system expansion and environmental... more

- by Bernardo Bezerra
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- Water resources, Agriculture, Power System Economics, Natural Gas

One of the impediments to large-scale use of wind generation within power systems is the non-dispatchability and its variable and uncertain real-time availability. Operating constraints on conventional generators such as minimum generation points, forbidden zones, and ramping limits as well as system constraints such as power flow limits and ancillary service requirements may force a system operator to curtail wind generation in order to ensure feasibility. Furthermore, the pattern of wind availability and electricity demand may not allow wind generation to be fully utilized in all hours. One solution to these issues, which could reduce these inflexibilities, is the use of real-time pricing (RTP) tariffs which can both smooth-out the diurnal load pattern in order to reduce the impact of binding unit operating and system constraints on wind utilization, and allow demand to increase in response to the availability of costless wind generation. We use and analyze a detailed unit commitment model of the Texas power system with different estimates of demand elasticities to demonstrate the potential increases in wind generation from implementing RTP.

- by Walter Short
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- Power System, Power System Economics, Unit Commitment, Real Time

The long-term electric power demand forecasting is
based on a set of basic premises that includes the macroeconomic
scenarios, the growth of the population and of the number of
households. The latter is the main determinant to calculate the
number of residential customers served by the utilities. This paper
presents the headship rate method and its projections for the
number of households in Brazil for the years 2010 and 2020. These
projections are based on the long term forecasting of the age
pyramid of the Brazilian population provided by the Brazilian
Institute of Geography and Statistics (IBGE). In order to forecast
the number of residential customers in the next ten years, the
projections for the number of households are combined with the
goals established by the Brazilian Electricity Regulatory Agency
(ANEEL) for universalization access to electricity.

- by José Francisco Pessanha
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- Business, Engineering, Electrical Engineering, Civil Engineering

Optimal Power Flow (OPF) is one of the main functions of Power Generation Operation and Control. It determines the optimal settings of generating units, bus voltage, and transformer tap and shunt elements in Power System with the objective of minimizing total production costs or losses while the system is operating within its security limits. The aim of this paper is to propose a methodology (GA-Matpower-OPF) that solves OPF including both active and reactive power dispatches. It is based on combining the Genetic Algorithm (GA) to obtain a near global solution, and the package of Matlab m-files for solving power flow and optimal power flow problems (Matpower) to determine the optimal global solution. This method was tested on the modified IEEE 57 bus test system. The results obtained by this method are compared with those obtained with GA or Matpower separately.

- by M. Rahli
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- Power Systems, Power System Economics, Genetic Algorithm, Optimal Power Flow

Throughout the world significant development is being encouraged in wind energy for electricity generation. A complete cost and benefit analysis has been conducted in this paper on grid connected wind generation. It takes into account system costs such as reserve requirements, start-up and ramping implications for conventional plants as well as wear and tear costs. The benefits of wind generation analysed include the emissions benefits, the saving on the fuel bill, the electricity generated and the capacity value. These costs and benefits are then used to generate net benefit curves for wind generation and the sensitivities of the curves are tested with changes in the underlying assumptions. A complete unit commitment model with wind generation is used to determine the dispatches upon which the costs and benefits are calculated.

- by John Gerald
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- Wind Energy, Power System Economics, Quantitative analysis, Power Generation
- by Kirit Parikh
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- Climate Change, Economic Growth, Human Development, Energy Consumption
- by Vicente Salas
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- Engineering, Law, Constitutional Law, Air Quality

- by Walter Short
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- Power System, Power System Economics, Unit Commitment, Real Time

The reform process in the electricity sector of any country has as main objective the design of a power market capable to induce a reliable and efficient energy supply, translated into adequate tariffs. Brazil started its reform process in 1996, inspired by similar schemes in the electricity sector of more developed countries. However, the existence of particularities in the country's hydroelectric energy market, such as weak spot price signals for system expansion and difficulties to determine benchmark prices, avoided a smooth transition to a fully deregulated market. In 2004, a revisited power sector model was launched, aiming at alleviating the difficulties of the first model. The core of the new proposals lies on the use of contract obligation and energy supply auctions as the backbone for the efficient contracting and supply adequacy. Supply auctions were held in 2004-2005, with a volume of about 20,000 average MW contracted involving about 60 billion USD in financial transactions. This work discusses the implementation of auctions of energy contracts and call options in Brazil as part of the mechanisms to ensure supply adequacy adopted in the second stage of its power sector reform

- by Mario Pereira
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- Power System Economics, Developing Country, Power Engineering, Energy Markets

The deployment of small (1-2 MW) clusters of generators, heat and electrical storage, efficiency investments, and combined heat and power (CHP) applications (particularly involving heat-activated cooling) in commercial buildings promises significant benefits but poses many technical and financial challenges, both in system choice and its operation; if successful, such systems may be precursors to widespread microgrid deployment. The presented optimization approach to choosing such systems and their operating schedules uses Berkeley Lab's Distributed Energy Resources Customer Adoption Model (DER-CAM), extended to incorporate electrical and thermal storage options. DER-CAM chooses annual energy bill minimizing systems in a fully technology-neutral manner. An illustrative example for a hypothetical San Francisco hotel is reported. The chosen system includes one large reciprocating engine and an absorption chiller providing an estimated 11% cost savings and 8% carbon emission reductions under idealized circumstances. Index Terms-Buildings, building management systems, cogeneration, cooling, cost optimal control, dispersed storage and generation, distributed control, optimization methods, power system economics, power system planning. I. INTRODUCTION H EREIN, the working definition of a microgrid is: a cluster of electricity sources and (possibly controllable) loads in one or more locations that are connected to the traditional wider power system, or macrogrid, but which may, as circumstances or economics dictate, disconnect from it and operate as an island, at

- by Chris Marnay
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- Engineering, Power Systems, Optimal Control, Power System Economics

improvement of the power system economical dispatch from voltage stability margin viewpoint is studied in this paper and for that a methodology is proposed. The considered time interval is short term operation. Active and reactive power (generation) re-dispatch injection is the basis of proposed method and voltage stability will be achieved using generated reactive power by shunt capacitors in power system. This method is implemented via modal analysis with specifying participation factor of generators and Synchronous condensers (units), and shunt capacitors. Using modal index, units with negative impact on voltage stability margin are revealed and penalized with high costs in objective function of the optimal power flow program used to run the re-dispatch process. Results indicate significant improve in voltage stability margin. So, the new method is applied in order to update penalty factor of units. In this research it is assumed that contingency occurred in system does not lead ...

- by hamed omidi
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- Engineering, Power System, Modal Analysis, Power System Economics

- by Rishabh Gupta
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- Electrical Engineering, Renewable Energy, Energy, Power System Economics