pricing for system security power tariffs security in power systems refers to the ability of the system to withstand imminent disturbances contingencies maintaining security is an issue which must be addressed at the system level it is shown in this paper however that it is possible to maintain power system security in an operating environment with many participants power companies independent power producers co generators consumers each attempting to optimize their own benefit through pricing incentives and appropriate information exchange rates for power generation consumption and for an offer to use during a contingency as well as information on the probability distribution of contingency need for each participant are derived so that individual optimization will lead to the socially optimal solution in which power system security is optimized and the aggregate benefit is maximized

targeting assistance to the poor efficient allocation of transfers when household income is not observed abstract this paper examines the problem of how to transfer money or other forms of assistance to poor households when one observes some characteristics of households but not their incomes this and related issues are often referred to as the targeting problem the paper first sets out the problem formally as one of minimizing a poverty index given a fixed amount of money available for transfers assuming that household survey data are available which include accurate income and or expenditure information the solution for the problem is formulated as a non linear mathematical programming exercise using household survey data from cote d ivoire the technique is applied to both urban and rural areas separately the paper concludes with a general discussion and suggestions for future research

market clearing with stochastic security part i formulation the first of this two paper series formulates a stochastic security constrained multi period electricity market clearing problem with unit commitment the stochastic security criterion accounts for a pre selected set of random generator and line outages with known historical failure rates and involuntary load shedding as optimization variables unlike the classical deterministic reserve constrained unit commitment here the reserve services are determined by economically penalizing the operation of the market by the expected load not served the proposed formulation is a stochastic programming problem that optimizes concurrently with the pre contingency social welfare the expected operating costs associated with the deployment of the reserves following the contingencies this stochastic programming formulation is solved in the second companion paper using mixed integer linear programming methods two cases are presented a small transmission constrained three bus network scheduled over a horizon of four hours and the ieee reliability test system scheduled over 24 h the impact on the resulting generation and reserve schedules of transmission constraints and generation ramp limits of demand side reserve of the value of load not served and of the constitution of the pre selected set of contingencies are assessed

quantification of market performance as a function of system security the tight coupling between market and system operations in the restructured environment requires a thorough understanding of the interdependence between the market performance and the way the power systems are operated in particular we need to go beyond the qualitative characterization and to quantify the dependence of the market performance on the system security such studies are typically not performed in today s regional transmission organization or rto structures in this paper we develop a general approach to quantify the monetary impacts of complying with a specified security criterion when the deployment of appropriate preventive and or corrective security control actions is fully taken into account this approach is deployed in the day ahead electricity markets and is based on the emulation of the way the rto currently operates the market and the grid the latter in compliance with the security criterion the proposed approach has a wide range of applications such as comparative market performance assessments of different security criteria and the cost benefit analysis of network improvements to mitigate the market performance impacts of a set of specified contingencies we illustrate the application of the proposed approach on the large scale iso ne system to quantify the monetary impacts associated with changing from the current security criterion to two other criteria using the actual 2005 day ahead data the historical system model and the bids offers submitted with the actual market clearing methodology these studies capture in a meaningful way the impacts of the changes with respect to the current security criterion an important finding of this study is that the economic efficiency of electricity markets need not decrease when the system is operated under a stricter criterion

reserve requirements to efficiently manage intra zonal congestion the security constrained unit commitment problem schedules power generators to minimize cost subject to operating constraints reserve requirements ensure that reserve is available to re balance the system following a contingency but do not guarantee reliability in congested systems where reserve activation is limited by transmission constraints operators improve reserve deliverability by limiting power flows and controlling the location of reserves zones are used to address inter zonal congestion but operators lack efficient ways to handle intra zonal congestion we propose dynamically relating minimum reserve levels to transmission stress in a computationally efficient approach that complements existing reserve models from the literature analysis on the ieee rts 96 test case demonstrates the approach can mitigate intra zonal congestion more economically than traditional reserve policies

stochastic security for operations planning with significant wind power generation in their attempt to cut down on greenhouse gas emissions from electricity generation several countries are committed to install wind power generation up to and beyond the 10 20 penetration mark however the large scale integration of wind power represents a challenge for power system operations planning because wind power 1 cannot be dispatched in the classical sense and 2 its output varies as weather conditions change this warrants the investigation of alternative short term power system operations planning methods capable of better coping with the nature of wind generation while maintaining or even improving the current reliability and economic performance of power systems to this end this paper formulates a short term forward electricity market clearing problem with stochastic security capable of accounting for nondispatchable and variable wind power generation sources the principal benefit of this stochastic operation planning approach is that when compared to a deterministic worst case scenario planning philosophy it allows greater wind power penetration without sacrificing security

market clearing with stochastic security part ii case studies this paper analyzes the market clearing formulation with stochastic security developed in its companion paper through two case studies solved using mixed integer linear programming techniques the generation and reserve schedules as well as the nodal prices of energy and security are assessed under various conditions such as a line flow limits b when nonspinning reserve is excluded from the formulation c demand side valuation of energy not served d generator ramping limits and e the set of pre selected contingencies

two stage stochastic programming model for market clearing with contingencies planning for contingencies typically results in the use of more expensive facilities before disruptions it leads to different prices and energy availability at various network locations depending on how the contingency analysis is performed in this paper we present a two stage stochastic programming model for incorporating contingencies the model is computationally demanding and made tractable by using an interior point log barrier method coupled with benders decomposition the second stage optimal recourse function rf defines the most economically efficient actions in the post contingency state for returning the system back to normal operating conditions the approach is illustrated with for two examples small with 8 buses 11 branches and ieee medium scale with 300 buses 411 branches

the effect of demand elasticity on security prices for the poolco and multi lateral contract models optimum power flows and security constrained power flows assume that customer demand is a fixed quantity in the new competitive environment it is necessary to assume that demand is elastic and will vary as a function of price a critical element in any competitive model whether it be a poolco or a multi lateral contract model is for a system operator to ensure reliability and feasibility of the power system operating point security pricing for feasibility was first advanced by schweppe et al for the case of line flow constraints for a poolco model using geometry this paper generalizes the approach to include any security constraint for a general competitive model the paper discusses interpretations of security pricing and its possible implementation in energy management systems

can developing country exports keep growing in the 1980s this paper reports on the initial findings of the program of studies on the impact of developing country exports of manufactures on the market of the principal industrial countries a discussion of the liberal protectionist balance leads to the conclusion that while quantitative assessments have been made of the decrease of protection through tariff reductions in the 1970 s it has not been possible to measure the increases in protection resulting from various other measures it seems that the resurgence of non tariff protectionism in the 1970s has not destroyed the liberal gains of earlier decades analysis of market penetration suggests the industrial countries market for ldc manufactures is large and still growing it appears that the liberal protectionist balance in the 1980s will be critical particularly for lower income and less successful developing countries policies to make liberal attitudes to trade dominant are suggested

optimal lmp decomposition for the acopf calculation the objective of this work is to design a suitable rule for the energy reference selection in the ac optimal power flow acopf based locational marginal price lmp calculation in the case of the acopf model the congestion component of the lmp vector exhibits strong dependence on the energy reference this in turn makes the hourly values of financial transmission rights ftrs to be reference dependent and thus is a source of dispute in order to resolve this dispute a direct optimization framework is developed in this work exploring the interrelationship between the congestion components of locational marginal prices at individual buses the objective function and the constraints of this optimization model are carefully designed looking at the true motive of the lmp decomposition at the same time necessary attention is paid so as to ensure revenue adequacy in the ftr settlement the optimization problem that is ultimately to be solved is a simple quadratic programming problem with only one variable and two constraints the effectiveness of the proposed methodology is verified through a case study on a modified ieee 30 bus system the framework developed also unveils several interesting features of the lmp components that were under cover until now

a security constrained bid clearing system for the new zealand wholesale electricity market this paper reports upon the mathematical models and implementation of the scheduling pricing and dispatch spd application for the new zealand electricity market nzem spd analyzes bids for energy offers reserve offers and energy demands and recognizes explicitly the effects on bid clearing due to transmission congestion network losses reserve requirements and ramp rate limits advanced lp solution methods are utilized to solve the large scale constrained optimization problem results on a 67 bus test system and the nzem are included

towards full integration of demand side resources in joint forward energy reserve electricity markets this paper proposes a security constrained forward market clearing algorithm within which the inherent characteristics of demand flexibility are acknowledged when the provision of reserve from the demand side is considered in the proposed formulation we co optimize the cost of scheduling the appropriate resources to guarantee the security of the system and the expected cost of operating under any credible system state in addition we consider that consumers can offer to provide spinning reserve capacity deployable by voluntary load reductions in response to contingencies due to the load recovery effect i e since energy usage is essentially postponed when demand side reserve is deployed in post contingency states any voluntary reduction in the load has to be accompanied by a subsequent increase in demand from the initial forecast we demonstrate that the marginal value of the reserve provided by the demand can only be calculated taking into account the cost of supplying the recovery consumption flexible consumers can reduce their payments on average if energy is settled through real time prices

energy and reserve pricing in security and network constrained electricity markets this paper analyzes some unresolved pricing issues in security constrained electricity markets subject to transmission flow limits although the notion of separate reserve types as proposed by ferc can be precisely and unambiguously defined when transmission constraints are active the very existence of separate reserve prices and markets is open to question when the prices are based on marginal costs instead we submit here that the only products whose marginal costs can be separately and uniquely defined and calculated are those of energy and security at each node thus under marginal pricing at any given network bus all scheduled reserve types should be priced not at separate rates but at a common rate equal to the marginal cost of security at that bus furthermore we argue that nodal or area reserves cannot be prespecified but must be obtained as by products of the market clearing process simulations back up these conclusions

market implications and pricing of dynamic reserve policies for systems with renewables static reserve policies are used within security constrained unit commitment scuc and security constrained economic dispatch sced to ensure reliability a common policy is that 10 min reserve must exceed the largest contingency however this condition does not guarantee reliability because voltage and thermal limits can hinder reserve deliverability many operators use zonal reserve markets to ensure reserves are dispersed across the grid such zonal models attempt to anticipate transmission bottlenecks which is a difficult task when the future system state is uncertain this paper examines the market implications of dynamic reserve policies used to mitigate uncertainty from renewable resources and contingencies we study the market implications of policies recently proposed in the literature such as hourly zones within day ahead scuc and an algorithm that formally disqualifies reserves that are expected to be undeliverable a locational reserve pricing scheme is also proposed in connection with scenario based reserve disqualification analysis on the rts 96 test case shows that dynamic zones and reserve disqualification along with the proposed compensation scheme help direct reserve payments toward resources that more effectively respond to contingencies

optimal dispatch of a system based on offers and bids a mixed integer lp formulation the federal energy regulatory commission s ferc orders 888 and 889 will have far reaching consequences on the operation and dispatch of electric power systems a common element of the change is that of dispatching the system based on offers and bids to sell and buy unbundled commodities this paper formulates and solves the optimal dispatch problem as a mixed integer linear program such a formulation allows the acceptance of offers with minimum takes arising from generator characteristics

pricing energy and reserves using stochastic optimization in an alternative electricity market this paper presents a stochastic linear programming model that can be used for pricing in electrical energy and reserve markets it addresses capacity energy and reserve dispatch problems that may arise from n 1 contingency scenarios possible market solutions focusing on generator compensation using real time day ahead and hybrid schemes are enumerated along with opportunities for consumer pricing and transmission costing this model is illustrated on a 6 bus test system as well as a larger 66 bus system representing the ontario network a key difference among schemes is the degree of risk to the generators measured by variance in profit

pricing electricity in pools with wind producers this paper considers an electricity pool that includes a significant number of wind producers and is cleared through a network constrained auction one day in advance and on an hourly basis the hourly auction is formulated as a two stage stochastic programming problem where the first stage represents the clearing of the market and the second stage models the system operation under a number of plausible wind production realizations this formulation co optimizes energy and reserve and allows deriving both pool energy prices and balancing energy prices these prices result in both cost recovery for producers and revenue reconciliation a case study of realistic size is used to illustrate the functioning of the proposed pricing scheme

differential evolution algorithm for security constrained energy and reserve optimization considering credible contingencies reserve services are an essential part of a standard market design and are under development in major electricity markets this paper presents the development of differential evolution algorithm for optimal allocation of energy and spinning reserve the optimization is performed in an integrated market with biddable spinning reserve and sectional price offer curves while considering all security and power systems constraints in steady state and system credible contingencies the effectiveness of the proposed method is examined by application of the proposed algorithm on the ieee 30 bus test system some comparisons are made with analytical and evolutionary methods in various cases

a game theoretical pricing mechanism for multi area spinning reserve trading considering wind power uncertainty the rapid development of wind power has led to an increased demand for spinning reserve in power systems today however one of the most severe challenges to china s power systems is the mismatch between wind power installation capacity and the capability for supplying spinning reserve within each independently operated provincial power system coordinating the spinning reserve across multiple areas would providentially improve the accommodation of wind power this paper proposes a game theoretical model for spinning reserve trading between provincial systems that treat spinning reserve as a commodity based on the incomplete information the trading price is calculated by satisfying the bayesian nash equilibrium and then the trading quantity is determined this ensures that both the buyer and the seller are able to maximize their expected profit case studies are performed using a 2 bus interconnected system and a 3 area ieee rts system the results show that the proposed model is valid and effective

incorporating post zonal reserve deployment transmission constraints into energy and ancillary service co optimization this paper presents a new approach implemented in miso day ahead and real time energy and ancillary service market clearing processes to address the reserve deliverability issue in this approach miso enhanced the co optimization process to incorporate post zonal reserve deployment transmission constraints reserves are procured within the co optimization to meet both market wide reserve requirements and ensure their deliverability on a zonal basis as a result zonal market clearing prices mcps for reserves can properly reflect the effects of zonal reserve deployment on transmission constraints under consideration

can the east asian model of development be generalized abstract export led growth has become increasingly popular among analysts and some governments as a development strategy besides contrasting its virtues to the distortions of the import substitution model popular through the 1960s advocates of the model frequently illustrate its merits by pointing to the remarkable success of its most prominent practitioners the east asian gang of four hong kong korea singapore and taiwan this study explores a possible limitation of the model known as the fallacy of composition while the model may work well if pursued by a limited number of countries it may break down if a large majority of developing countries seeks to pursue it at the same time because the resulting outpouring of manufactured exports might be more than western markets could absorb protectionist response might be the result of attempts to generalize the east asian export model of growth

spot pricing of capacities for generation and transmission of reserve in an extended poolco model the poolco model is emerging as one of the most acceptable options for organizing the spot market of electricity although the model represents a reasonable and safe transition from present industry practices to what is required in a competitive electricity market many important issues remain to be resolved in particular issues regarding reliability related services are of a special concern to the industry this paper is devoted to the issue of reserve service delivery and pricing the poolco model is extended in this paper to include spot pricing of reserve generation and transmission capacities as well as demand side bidding in the authors extended model suppliers submit bids for power as well as for reserve capacities a new formulation of the extended security constrained economic dispatch which allocates both power and reserve generation resources is presented in this paper the dispatch of the resources is constrained by limitations of system transmission capacities the proposed formulation is considered to be relevant not only in the poolco but in a more general setup an illustrative example is used to introduce concepts and present results finally some general issues regarding formats of proposals balance of payments and uniqueness of the prices that apply equally to both the original and extended poolco models are discussed

stochastic multiobjective market clearing of joint energy and reserves auctions ensuring power system security in this paper a stochastic multiobjective framework is proposed for day ahead joint market clearing the proposed multiobjective framework can concurrently optimize competing objective functions including augmented generation offer cost and security indices overload index voltage drop index and voltage stability margin besides system uncertainties including generating units and branches contingencies and load uncertainty are explicitly considered in the stochastic market clearing scheme the solution methodology consists of two stages which firstly employs roulette wheel mechanism and monte carlo simulation mcs for random adaptive 24 h scenario generation wherein the stochastic multiobjective market clearing procedure is converted into its respective deterministic equivalents scenarios in the second stage for each deterministic scenario a multiobjective mathematical programming mmp formulation based on the epsiv constrained approach is implemented for provision of spinning reserve sr and nonspinning reserve nsr as well as energy the mmp formulation of the market clearing process is optimized while meeting ac power flow constraints and expected interruption cost eic the ieee 24 bus reliability test system rts 24 bus is used to demonstrate the performance of the proposed method

demand side reserve offers in joint energy reserve electricity markets we propose a market model that includes demand side reserve offers and where energy and reserve are jointly dispatched generators and consumers can submit offers and bids on five distinct products energy upspinning reserve downspinning reserve and two kinds of standby reserve the resources are scheduled and dispatched in a joint auction through a mixed integer optimization program the extra scheduling flexibility introduced by demand side reserve offers can lead to significant gains in economic efficiency thus the results suggest that not only do the consumers increase their profits but in addition the market power of the generators is reduced

framework for energy brokerage system with reserve margin and transmission losses the power industry in the united states is presently participating in a changing business environment while planning to meet future peak demand is still a concern the efficient utilization of existing generation and transmission resources is fast becoming of primary interest this interest suggests to move from cost based market operations to price based market operations in such a business environment a need for a mechanism to determine the pricing of various ancillary services is desired as the ancillary services go together with electrical power transfer the proposed approach develops a novel method of pricing mechanism for reserve margins and transmission losses as a part of the overall transaction in an energy brokerage system the brokerage model described in this paper is based on formulations using linear programming