role of distribution factors in congestion revenue rights applications in the locational marginal price lmp based congestion management scheme transmission customers face uncertainty in the congestion charges they incur in order to bring certainty to customers congestion revenue rights crr such as the fixed transmission rights ftr used in the pjm interconnection and flowgate rights fgr are introduced these crr are financial tools that provide the holder reimbursement of the congestion charges incurred in the day ahead market the implementation of crr requires appropriate modeling of the transmission network in which the distribution factors are extensively used these factors the injection shift factors isfs and the power transfer distribution factors ptdfs are linear approximations of the sensitivities of the active power line flows with respect to various variables the factors are computed for a specified network topology and parameter values in practice the ptdfs used for the crr issuance may be different from those used in the day ahead market due to changes in the forecasted network conditions the ptdf errors may impact the ftr issuance quantities the revenue adequacy of the ftr issuer and the hedging ability of the fgr in this paper we explore analytical characteristics of these distribution factors and investigate their role in crr applications we study the nature of the ptdf errors and examine their impacts in these applications both analytically and experimentally our results indicate that the impacts of the ptdf errors in crr applications stay in an acceptable range under a broad spectrum of conditions including contingencies used to establish n 1 security

learning to believe in sunspots a number of authors have shown that competitive economies may possess sunspot equilibria that is rational expectations equilibria in which purely extrinsic uncertainty affects equilibrium prices and allocations 2 such results demonstrate that it does not require a lack of faith in the rationality of market participants to believe that competitive markets may be subject to purely speculative fluctuations driven solely by expectations 3 the mere existence of sunspot equilibria as solutions to a system of marketclearing conditions however might not be judged sufficient to indicate that competitive markets with rational participants could ever be subject to speculative instability the sunspot equilibria represent states of affairs in which agents act differently in the case of different realizations of the sunspot variable and it is rational for each agent to do so but it might be thought unlikely that the beliefs of all the participants in the market could ever come to be coordinated so as to bring about an equilibrium of that kind it is rational to believe that sunspots convey information about future states of affairs once the economy is in a sunspot equilibrium but why would rational agents ever begin to believe in such a thing so as to create the conditions under which the belief is rational in order to address such a question one must go beyond the mere statement of the conditions for equilibrium and discussion of what states of affairs satisfy them one must specify an explicit dynamic process according to which the beliefs of agents adjust when out of equilibrium any exercise of this kind is necessarily unsatisfactory as there is no univocal meaning for the postulate of rational behavior outside of an equilibrium it may well be the case that

alternative models of restructured electricity systems part 1 no market power different equilibrium concepts have been proposed by various authors schweppe et al hogan et al chao and peck wu et al to analyse competitive electricity systems we establish correspondences between these different models through a single framework and provide additional interpretations of these equilibrium concepts this unifying conceptual view also provides a computationally feasible approach to simulate the market it also opens the way to the modeling of some imperfect markets

transmission access and pricing with multiple separate energy forward markets california s congestion management protocols provide comparable access and prices to all users of the transmission system power exchange and bilateral contract parties the users implicitly bid for capacity on major transmission paths between zones the independent system operator iso allocates the available transmission capacity on these paths so that it maximizes the value of this capacity as measured by the users bids everyone scheduling flow on a congested path is charged the marginal cost based price for using the path the iso keeps each party s portfolio of generation and load individually in balance when adjusting schedules to relieve congestion on interzonal paths by keeping the portfolios of the different parties separate the iso clears its transmission market without arranging energy trades between parties parties are responsible for arranging their own trades the iso does not become involved in the energy forward markets

optimization based approach for price multiplicity in network constrained electricity markets this paper addresses the problem of price multiplicity in network constrained pool based electricity markets under marginal pricing this problem consists in the existence of multiple vectors of locational marginal prices for the same optimal market clearing dispatch solution as a consequence delicate conflicts of interest may arise among market participants price multiplicity may take place even in auction designs based on convex formulations for the market clearing procedure an effective duality based solution approach is proposed in this paper to handle the issue of price multiplicity once the optimal market clearing dispatch is known we propose the subsequent solution of a simple pricing problem in order to determine the vector of locational marginal prices unlike previously reported methodologies the proposed approach presents two salient features 1 it is based on sound mathematical programming and 2 it is computationally inexpensive since it relies on the solution of a linear program numerical results are provided to illustrate the performance of the proposed tool

min max regret bidding strategy for thermal generator considering price uncertainty the electricity price volatility brings challenges to bidding strategies in the electricity markets in this paper we propose a minimax regret approach for a market participant to obtain an optimal bidding strategy and the corresponding self scheduled generation plans motivated by recently proposed robust optimization approaches our approach relies on the confidence intervals of price forecasts rather than point estimators we reformulate the minimax regret model as a mixed integer linear program milp and solve it by the benders decomposition algorithm moreover we design a bidding strategy based on the price forecast confidence intervals to generate the offer curve finally we numerically test the minimax regret approach in comparison with the robust optimization approach on three types of thermal generators by using real electricity price data from pjm to verify the effectiveness of our proposed approach

marginal loss modeling in lmp calculation this paper discusses the pricing of marginal transmission network losses in the locational marginal pricing approach recently deployed in the iso new england iso ne standard market design smd project implemented by alstom s t d energy automation and information eai business the traditional loss model is studied and a new model is proposed the new model achieves more defendable and predictable market clearing results by introducing loss distribution factors to explicitly balance the consumed losses in the lossless dc power system model the distributed market slack reference is also introduced and discussed the lmp components produced by the two models are studied and compared under changes in slack reference numerical examples are presented to further compare the two models

contingent transmission rights in the standard market design we define transmission rights that are compatible with the federal energy regulatory commission s proposed standard market design smd and that provide flexibility in the points of receipt or delivery of energy contracts the contingent transmission rights introduced here provide a viable flexible method for defining smd compatible rights for transmission customers having current pre smd transmission rights that cover multiple points these contingent rights can be bought and sold in the transmission rights auctions under smd

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

determinants of portfolio performance ii an update 1991 determinants of portfolio performance ii an update financial analysts journal vol 47 no 3 pp 40 48

financial storage rights should energy storage buy and sell power at wholesale prices like utilities and generators or should its physical and financial operation be asynchronyous as with transmission lines in the first case storage straightforwardly profits through intertemporal arbitrage also known as load shifting and peak shaving in this paper the latter case referred to as passive storage is examined because passive storage does not make nodal price transactions new mechanisms are necessary for its integration into electricity markets this issue is addressed by further developing the analogy between energy storage and transmission specifically financial rights are defined for storage and tracing is extended to multiperiod power flows linked by storage like flowgate transmission rights the new financial storage rights redistribute the system operator s merchandising surplus and enable risk averse market participants to hedge against nodal price volatility resulting from storage congestion simple examples are given demonstrating the implementation of the new mechanisms game theoretic analysis suggests that financial storage rights mitigate gaming when both the generator and load bid strategically

an iterative lmp calculation method considering loss distributions generally the locational marginal price lmp is obtained by solving a linear programming formulation network losses are considered through the preset loss factors based on historical operation information this usually brings errors in the calculated loss under different new scenarios further the congestion component of an lmp is dependent on the choice of the reference bus in this paper a new iterative lmp calculation method is proposed to overcome the aforementioned two drawbacks associated with the traditional lmp calculations at each iteration a linear programming problem for market clearing is solved first losses on branches are considered as fictitious nodal demands at their terminal buses secondly the ac power flow is calculated according to the dispatch results loss factors and fictitious nodal demands are then updated according to the ac power flow solution thus removing the need and dependence on presetting loss factors another important merit is that lmp and its congestion component obtained from the proposed iterative lmp calculation method are independent of choice of the reference bus the effectiveness of the proposed method is illustrated on two benchmark systems the importance of obtaining accurate losses and lmps is also demonstrated

sector style region explaining stock allocation performance the importance of asset allocation policy in stock bond portfolios is widely recognized drawing a parallel for equity only portfolios this study analyzed the importance of allocation by economic sector and by size and style in purely u s stock portfolios and the importance of regional allocation policy in international stock portfolios the study found that allocation policy explains one third to nearly three quarters of among fund variation in returns nearly 90 percent of across time variation and more than 100 percent of the level of stock portfolio returns

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

advanced pricing in electrical systems i theory this paper sets forth a comprehensive theory for the real time pricing of electricity that includes selected ancillary services and extends the theory to incorporate constraints on power quality and environment impact that often influence the operation of a power system this paper is part i of a two paper set it sets forth the mathematical development of the extended model for real time pricing the formulation is novel in that it combines the dynamic equations for load frequency control with the static equations of a constrained optimal power flow part ii derives optimal nodal specific real time prices for both real and reactive power the prices derived include additive premia or opportunity costs reflecting the effects of voltage regulation maintenance of generation and transmission reserves regulation of frequency and tie line flows removal and or control of power harmonics and others

a comprehensive assessment of the evolution of financial transmission rights financial transmission rights ftrs are complementary to the locational marginal pricing of energy the basic aim of the ftr mechanism is to guard forward contracts from uncertain congestion charges ftrs are also useful to individual generators and loads for selling and buying power respectively at the prices of other locations the concept has evolved encompassing many features such as a simultaneous feasibility test various ways to conduct auctions and allocations and secondary trading ftrs also have a close relation to market power and transmission investment this paper reviews most of the landmark research papers on the evolution of the ftr concept it reports a comprehensive assessment of various facets of ftrs and allied issues financial transmission rights and flowgate rights fgrs are compared the concept of long term ftrs is discussed the paper also touches upon future proposals in this area

evolution toward standardized market design the evolution toward the standardized market design smd is presented in this paper with references to the market developments in new zealand australia pjm iso ne and ercot in the development of market designs two main objectives market liquidity facilitating bilateral trading and pricing efficiency facilitating congestion management have been pursued the efforts to balance the seemingly conflicting objectives led to most markets designed with a uniform or zonal pricing model introduction of locational marginal pricing and evolution of transmission rights from physical to financial form made it possible to harmonize the potentially conflicting goals in a market design the close coupling between energy and ancillary services requires that markets for these commodities be carefully coordinated different operational practices and reliability standard requirements have led to major differences in ancillary service market designs

network constrained economic dispatch using real coded genetic algorithm a genetic algorithm ga solution to the network constrained economic dispatch problem is presented a real coded ga has been implemented to minimize the dispatch cost while satisfying generating unit and branch power flow limits a binary coded ga was also developed to provide a means of comparison ga solutions do not impose any convexity restrictions on the dispatch problem the proposed method was applied on the electrical grid of crete island with satisfactory results various tests with both convex and nonconvex unit cost functions demonstrate that the proposed ga locates the optimum solution while it is more efficient than the binary coded ga

on the political economy of uk pension scheme regulation we take the opportunity of the recent consultation exercise on uk defined benefit pension schemes conducted by the pensions regulator to examine the approach to pension scheme portfolio management that it and the related pension protection fund have adopted after summarising the regulatory basis we identify three essential building blocks for further examination the notion of matching liabilities to long term government bonds the use of standard deviation of return as a measure of risk and the idea that strategic asset allocation is the most important decision in portfolio management this last one the brinson axiom we examine these foundations individually and then collectively with the aid of two unobtrusive postulates the first being the efficient markets hypothesis and the second that pension scheme assets should be used to purchase only those securities with minimal default risk from the perspective of what we have elsewhere called the keynes graham schema we conclude that the foundations are unsound and that the conventional approach adopted not only by both the regulator and the protection fund but also by the major actuarial consultancies induces if not actually requires pension schemes to engage in speculation rather than investment

introduction to multidimensional financial transmission rights this paper introduces the concept of multidimensional financial transmission right mdftr which is a generalized group financial transmission right ftr concept an mdftr allows its owner to hold a total ftr amount over a path group along with multiple choices to distribute this grouped amount among the individual grouping paths this added flexibility provides forward market participants with a useful support to overcome the congestion price risk that originates from the uncertainty in their transaction paths all the fundamental issues regarding the implementation of mdftrs are addressed in detail in this paper the practical utility of mdftrs is judged by analyzing their costs it is shown with illustration that an mdftr may be more cost effective than any given portfolio of individual ftrs that has the ability to give the same risk hedging benefit

border flow rights and contracts for differences of differences models for electric transmission property rights in this paper a property rights model for electric transmission is proposed and its properties analyzed the proposed rights called border flow rights support financial hedging of transmission risk and merchant transmission expansion through associated financial rights called contracts for differences of differences these financial rights allow for forward trading of both energy and transmission by a unified exchange avoiding the bifurcation in current markets between decentralized long term energy trading and centralized long term transmission trading such long term trading can help to support the financing of both generation and transmission assets we consider incentive properties of such a right in the absence of lumpiness economies of scale and market power

transmission congestion management in competitive electricity markets this paper studies the management of costs associated with transmission constraints i e transmission congestion costs in a competitive electricity market the paper examines two approaches for dealing with these costs the first approach is based on a nodal pricing framework and forms the basis of the so called pool model the paper also provides an analysis of financial instruments proposed to complement nodal pricing and includes illustrative test results on a large scale system the second approach is based on cost allocation procedures proposed for the so called bilateral model the paper explains the basis for this model including a game theoretic evaluation of some of its aspects both the pool and bilateral models have been at the center of the electric utility restructuring debate in california

an oligopolistic model of an integrated market for energy and spinning reserve in this paper a model for oligopolistic competition in electricity markets is presented most previous proposed models have been static and focused only on the energy market incentives for strategic behavior in contrast in this paper a multiperiod market for energy and spinning reserve sr is considered by including such factors the competition among participants is modeled with more realism competition in the energy market is modeled by means of conjectured supply functions while conjectured reserve price response functions are used to consider the generators ability to alter the sr prices the resulting equilibrium problem is modeled in terms of complementarity conditions based upon a complementarity model the opportunity cost between the energy and sr markets is derived for oligopolistic markets the proposed model is illustrated by a six node network using a dc approximation

dcopf based marginal loss pricing with enhanced power flow accuracy by using matrix loss distribution on current days many of the power markets are adopting the practice of marginal loss pricing the dc optimal power flow dcopf model is still mostly used for the purpose of market clearing owing to its simplicity robustness and higher speed of convergence within the dcopf framework transmission line losses are represented as additional external loads on the system in the classical dcopf model of marginal loss pricing as implemented in the new england market the aggregated network loss is distributed over the system nodes in a fixed ratio to gain more design flexibility in the distribution of system losses a matrix loss distribution mld framework is developed in this paper maintaining compatibility with financial transmission rights in mld each individual line is considered separately for the purpose of loss distribution the ratio in which the power loss in a certain line is distributed can be different from that in which the power loss in another line is distributed the additional design flexibility thus obtained assists in making a more accurate representation of the power flow the benefit of mld is illustrated through a case study an energy reference independent application of mld is also suggested

risk constrained ftr bidding strategy in transmission markets in electricity markets financial transmission right is an important instrument for hedging congestion charges there are two types of financial transmission rights point to point right ftr and flow based right fgr this paper proposes a risk constrained ftr bidding strategy in transmission auction markets based on the forecasted lmp differences between sink and source points of certain ftrs bidders try to maximize their expected payoffs by taking into account the associated risks supposing the forecasted distribution of lmp differences and bidders risk preferences are known to respective bidders the ftr bidding problem is modeled as a bilevel optimization with the upper subproblem representing bidders and the lower subproblem representing the solution to the iso s ftr market clearing problem for maximizing the revenues collected from the ftr auction the bilevel optimization problem is solved by developing the sensitivity of a bidder s expected utility with respect to its bidding strategy a three bus system with four bidders is considered for illustrating the proposed method the numerical results discuss the distinction between ftr obligation and ftr option bidding strategies the results further demonstrate the impact of contingency constraints forecasted lmp differences and bidders preferred risk levels on ftr bidding strategies

locational marginal price sensitivities within an optimal power flow market clearing framework this paper provides expressions to compute the sensitivities of locational marginal prices with respect to power demands sensitivities with respect to other parameters can also be obtained an example and a case study are used to illustrate the expressions derived

bidding strategy of virtual power plant for participating in energy and spinning reserve markets part i problem formulation this paper addresses the bidding problem faced by a virtual power plant vpp in a joint market of energy and spinning reserve service the proposed bidding strategy is a non equilibrium model based on the deterministic price based unit commitment pbuc which takes the supply demand balancing constraint and security constraints of vpp itself into account the presented model creates a single operating profile from a composite of the parameters characterizing each distributed energy resources der which is a component of vpp and incorporates network constraints into its description of the capabilities of the portfolio the presented model is a nonlinear mixed integer programming with inter temporal constraints and solved by genetic algorithm ga

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

running a more complete market with the slp iv acopf the acopf is at the core of competitive electricity market design it is the only ac based algorithm that simultaneously co optimizes real and reactive power dispatch for steady state operations on ac power systems in practice independent system operators isos oversimplify the physical problem and settle the markets on locational marginal price lmps based on real power but do not price reactive power dispatch or voltage control this work proposes a market dispatch and pricing procedure based on the acopf to provide a more complete pricing mechanism we formulate the dual problem of the slp iv acopf as shown in 1 which is a successive linear program shown to solve the acopf to an acceptable quality of convergence to a best known solution with linear scaling of computational time in proportion to network size therefore the dual problem is also a linear program as a result the marginal value pricing of the optimal solution to the dual problem supports the market dispatch due to strong duality i e this solution technique results in a revenue adequate and more complete market design furthermore we show how to distribute the complete real time market settlements the analysis includes a direct comparison to dcopf based approaches similar to those applied in current iso markets

the place of portfolio management in the keynesian canon recent publications such as the two volume oxford handbook of post keynesian economics harcourt and kreisler 2013 and the elgar companion to post keynesian economics king 2012 provide authoritative summaries of the current state of the art on a very wide range of relevant topics in particular the contents pages of these books define the field as seen by adherents the obvious implication being that those topics excluded have not yet acquired the necessary status by passing appropriate academic tests of relevance and coherence inter alia the focus of this article portfolio management is on one of these omitted topics starting from the fundamental recognition of uncertainty we examine the whole range of characteristics of the keynesian approach demonstrating the coherence and applicability of its multidimensional nature in the process pointing by contrast to the one dimensional sterility of the conventional approach our general conclusion is that there is a rightful place in the keynesian canon for portfolio management by which we mean not only investment management but also speculative management where these two qualifiers are used in the keynes graham sense

convexity of the set of feasible injections and revenue adequacy in ftr markets the feasible set of power injections for the constrained power flow equations is nonconvex when practical transmission capacity and bus voltage limits are imposed the projection onto the space of active power injections may be close to convex but this is not sufficient to guarantee revenue adequacy for the settlement of financial transmission rights

the effect of contingency analysis on the nodal prices in the day ahead market we look at the effect of modeling branch outage contingencies on locational marginal prices to model contingencies in the day ahead auction we formulate a two stage stochastic program rather than follow the current practice of including a list of possible contingencies that must be satisfied we incorporate a larger set of contingencies in the model and allow contingencies to result in load reductions outages at a cost the model can be used and interpreted in two ways one is to look at the tradeoff between reliability and outage costs another is to consider the load losses resulting from a contingency to be consumer offers of load reductions in response to line outages as part of the day ahead auction in analyzing the model structure we find that the prices in the model closer in definition to those currently used in the day ahead auction do not maximize expected surplus because the day ahead auction produces prices that assume shortages will never occur this raises issues with the design of auctions with important stochastic elements in the market we present results for a 68 node grid with 86 branches lines and transformers to illustrate how prices and expected values change as the costs of outages are varied

components of nodal prices for electric power systems a method is presented to provide a detailed description of each nodal price for electric power systems by breaking down each nodal price into a variety of parts corresponding to the concerned factors such as generations transmission congestion voltage limitations and other constraints or elements this complete information for nodal prices can be used not only to improve the efficient usage of power grid and congestion management but also to design a reasonable pricing structure of power systems or to provide economic signals for generation or transmission investment several numerical examples demonstrate this approach

determinants of portfolio performance in order to delineate investment responsibility and measure performance contribution pension plan sponsors and investment managers need a clear and relevant method of attributing returns to those

transmission rights and transmission expansions in this paper we propose a new method of defining rights that may be assigned to the developer of a transmission expansion project they include a right to collect the value of the capacity provided by the expansion project as well as the value arising from the admittance of the expansion project this approach not only ties the rights allocation to actual physical characteristics of the transmission project but also allows such allocation to remain independent both of the order in which the projects are treated and of any previously allocated transmission rights

dc power flow revisited linear mw only ldquodcrdquo network power flow models are in widespread and even increasing use particularly in congestion constrained market applications many versions of these approximate models are possible when their mw flows are reasonably correct and this is by no means assured they can often offer compelling advantages given their considerable importance in today s electric power industry dc models merit closer scrutiny this paper attempts such a re examination

risk based locational marginal pricing and congestion management this paper develops a new electricity market clearing mechanism called risk based locational marginal pricing rlmp the rlmp is derived from the risk based security constrained economic dispatch model where risk is modeled to capture the system s overall security level compared to the traditional locational marginal pricing lmp which is composed of three components energy congestion and loss the rlmp consists of an additional risk component the risk component is a price signal to reflect the system s overall security level this paper discusses the features of rlmp and analyzes its benefits over traditional lmps the proposed concept and method are illustrated on a six bus system and the wecc 240 bus system

an energy reference bus independent lmp decomposition algorithm the volatility of the price of electricity in a locational marginal price lmp market makes it necessary to introduce financial price risk hedging instruments the congestion related and marginal loss related revenue surpluses collected by the regional transmission operator rto are proposed to be redistributed to market players it is important to be able to correctly decompose the lmp into its congestion and marginal loss components which are critical for the valuation and settlement of these financial instruments a new energy reference bus independent lmp decomposition model using an ac optimal power flow opf model is presented to overcome the reference bus dependency disadvantage of the conventional approach the marginal effect of the generators output variation with respect to load variation are used as the basis of this decomposition model the theoretical derivation and a proof are given the new model achieves a set of reference bus independent results an example is presented comparing the new model with the conventional model

advanced pricing in electrical systems ii implications part i of this paper set forth a mathematical formulation of a model for real time pricing of electricity that included selected ancillary services and extended the theory to incorporate constraints on power quality and environment impact that often influence the operation of a power system derived herein are optimal real time prices for both real and reactive power the optimal prices are temporally and spatially differentiated the prices derived include additive premia or opportunity costs reflecting the effects of voltage regulation maintenance of generation and transmission reserves regulation of frequency and tie line flows removal and or control of power harmonics and others this paper concludes with a discussion of the implications of the optimal prices for pricing of both retail and wholesale services

a penalty scheme for reducing electricity price volatility the deregulation of electric power systems in many parts of the world has changed the mechanism of electricity pricing unlike the fixed price in conventional power systems electricity price varies with time and location in the new deregulated environment electricity prices in a restructured power system can be highly volatile due to the random nature of system failures and demands it is therefore very difficult for the independent system operator iso to control the price and associated risk the high prices beyond control have resulted in significant impacts on customers as well as on system operation this paper proposes a penalty scheme for reducing electricity price volatility caused by failures in generation companies gencos or transmission companies transcos in this scheme gencos and transcos will be penalized if their equipment failures result in unexpected price changes the price decomposition technique is used to evaluate the price components caused by random failures the penalty can be calculated based on the difference of electricity price components between the normal state and the contingency states moreover a simplified schema which is based on profit analysis is also proposed in this paper the proposed penalty scheme not only gives the gencos and transcos an incentive to improve their reliabilities but also provides a flexible tool for the iso to control the system price risk the possible shortcomings of the proposed schema are also specified in the paper the ieee rts is analyzed to illustrate the technique

strong formulations for multistage stochastic self scheduling unit commitment with the increasing penetration of renewable energy into the power grid system the volatility of real time electricity prices increases significantly this brings challenges for independent power producers to provide optimal bidding strategies the traditional approaches of only attending the day ahead market might not be profitable enough without taking advantage of real time price volatility in this paper we study the optimal bidding strategies for the independent power producers utilizing self scheduling strategies to participate in the real time market considering real time electricity price volatility with the objective of maximizing the total expected profit considering the correlations of renewable energy generation outputs among different time periods the correlations of real time prices are captured in our modeling framework in which we explore a multistage stochastic scenario tree to formulate the price uncertainties accordingly the derived multistage stochastic self scheduling unit com

introduction to loss hedging financial transmission rights in order to guard forward contracts from the locational marginal price lmp volatility financial transmission rights ftrs are issued in the centralized power markets however the current ftr system can provide hedge only against the congestion components of lmp differentials consequently the loss components remain unhedged to bridge the gap a framework is developed in this paper to implement an ftr system that will provide hedge against the loss prices the availability of loss hedging ftrs in addition to the congestion hedging ftrs further reduces the exposure of the forward market participants to the lmp volatility the loss hedging framework developed is carefully designed to fit the practical environment all the primary issues for the implementation of loss hedging ftrs such as the revenue adequacy test auction and auction revenue rights are carefully addressed revenue adequacy of loss hedging ftrs can be ensured by means of a test called as the offset capacity test some efficient policies are also designed for the successful functioning of loss hedging ftrs at the end of the paper a case study is carried out to assess the effectiveness of the methodology developed

transmission management for congested power system a review of concepts technical challenges and development of a new methodology transmission networks have some constraints that should be addressed in order to ensure sufficient control to maintain the security level of a power system while maximising market efficiency the most obvious drawback of transmission constraints is a congestion problem that becomes an obstacle to perfect competition among the market participants since it can influence spot market pricing as the power flow violates transmission constraints redispatching generating units is required and this will cause the price at every node to vary this manuscript presents concepts technical challenges and methodology for investigating an alternative solution to the redispatch mechanism and then formulates lmp scheme using an optimisation technique that may well control congestion as the main issue the lmp scheme are varied and improved to take into account the energy price congestion revenue cost of losses as well as the transmission usage tariff by utilising shift factor based optimal power flow sf opf which is derived from the well known dc optimal power flow dc opf model

testing rebalancing strategies for stock bond portfolios across different asset allocations abstractwe compare the risk adjusted performance of stock bond portfolios between rebalancing and buy and hold across different asset allocations by reporting statistical significance levels our investigation is based on a 30 year dataset and incorporates the financial markets of the united states the united kingdom and germany to draw useful recommendations to investment management we implement a history based simulation approach which enables us to mimic realistic market conditions even if the portfolio weight of stocks is very low our empirical results show that a frequent rebalancing significantly enhances risk adjusted portfolio performance for all analysed countries and all risk adjusted performance measures

an analysis of the marginal value of electricity transmission lines in the dispatch possible applications the marginal value of transmission lines in the dispatch is widely used in the literature and has relevant practical applications related to planning the expansion of the transmission grid and computing the remuneration of merchant lines this paper presents a general formulation of the marginal value of a line in the dispatch that highlights the dependence of this value on the link between line admittance and capacity we discuss the value of a line according to marginal principles following a general approach and prove that only if the admittance of a line can be expressed as a linear function of its capacity or when admittance and capacity can be deemed independent is this value equal to the product of the difference between marginal electricity prices at both ends of the line and the flow through this line afterwards we show that under a set of stylized conditions the remuneration of efficient network investments according to their marginal value in the dispatch should result in an exact recovery of their cost finally we compute the marginal value of lines in a stylized though representative system for several relationships between line capacities and admittances to illustrate the theoretical results obtained

optimized ftr portfolio construction based on the identification of congested network elements this paper focuses on the construction of an optimized financial transmission rights ftr or congestion revenue rights portfolio for an ftr market participant given his assessment of the frequency and economic impacts of binding constraints in the transmission network we overcome the data handling and heavy computing demands of locational marginal price lmp difference based methods for ftr selection by recasting the problem into one that focuses on the underlying product of binding constraints which are physically observable phenomena based on the mathematical insights into the structural characteristics of the model used for the clearing of the hourly day ahead markets differentials in the lmps are due to system congestion and so are merely manifestations of binding constraints in the transmission network in addition we exploit extensively the salient topological characteristics of large scale interconnections the market participant specifies the subset of focus constraints and the position he is willing to take on them our approach builds on the mathematical insights and topological characteristics with the effective deployment of the orthogonal matching pursuit algorithm to construct the optimized ftr portfolio characterized by the minimum number of node pairs for the specification of the ftr elements we apply the proposed approach to a test system based on the pjm iso network and markets to illustrate its capabilities for solving the ftr market participant s problem in realistic large scale systems

spot pricing when lagrange multipliers are not unique classical spot pricing theory is based on multipliers of the primal problem of an optimal market dispatch i e the solution of the dual problem however the dual problem of market dispatch may yield multiple solutions in these circumstances spot pricing or any standard pricing practice based on multipliers cannot generate a unique clearing price although such situations are rare they can cause significant uncertainties and complexities in market dispatch in practice this situation is solved through simple empirical methods which may cause additional operations or biased allocation based on a strict extension of the principles of spot pricing and surplus allocation we propose a new pricing methodology that can yield unique impartial and robust solution the new method has been analyzed and compared with other pricing approaches in accordance with spot pricing theory case studies support the results of the theoretical analysis and further demonstrate that the method performs effectively in both uniform pricing and nodal pricing markets

implementation of lmp ftr mechanism in an ac dc system this paper analyzes the implementability of locational marginal price lmp and financial transmission right ftr mechanisms in the presence of high voltage dc hvdc lines in the regulated i e under the control of system operator network the established framework of lmp ftr mechanism assumes that the system under regulation is fully ac unregulated or private hvdc lines are taken into account within this framework through proxy transaction bids from the line owners however as the flow over a regulated hvdc line has to be controlled by the system operator himself the existing lmp ftr framework becomes insufficient if the system contains or is expanded with regulated hvdc lines the augmentation that should be made to the existing framework to include regulated hvdc lines is explained in this paper it is shown that the flow over a regulated hvdc line can be modeled as a non chargeable bilateral transaction without causing any threat of negative congestion surplus for this power dispatch model revenue adequacy of ftrs can be still ensured by means of the conventional simultaneous feasibility test sft model by utilizing the capacities of dc lines a more general sft model is further developed the modified auction problem is discussed and tested for the non negativity of net auction collection the process of revenue adequate issuance of auction revenue rights is explained finally the relative merit of a regulated hvdc line over a private hvdc line is discussed through a case study

a general formulation for lmp evaluation the evaluation of locational marginal prices or lmps which constitute the basis of the new generation of market design in the u s is a critical need in the side by side operation of electricity markets and power systems their use in various applications such as congestion management and hedging requires specific lmp components in the computations we provide a general formulation for the evaluation of the lmp components by making explicit use of the important role played by the nodes with generators with free capacity on the other hand the lmps of the nodes without generation or with the generators at their limits are a function of the lmps at the marginal nodes and the impacts of the network constraints including the losses in the network in the formulation we pay special attention to the importance of the assumptions and specifications the so called policy specification in the determination of the components we obtain a very general formulation that brings under a single framework the different decomposition approaches that exist the formulation s comprehensiveness brings numerous insights into the various decompositions provides a platform for their comparative analysis and allows us to understand the direct implications and the role of the policy specified moreover the formulation reveals the limitations of any decomposition into the components due to the underlying structural interdependencies among them which is clearly shown in this paper we provide an example to illustrate the capabilities and the insights obtainable with the use of this formulation

congestion management schemes a comparative analysis under a unified framework the restructuring of the electricity industry has spawned the introduction of new independent grid operators igos typically called transmission system operators tsos independent system operator isos or regional transmission organizations rtos in various parts of the world an important task of an igo is congestion management cm and pricing this activity has significant economic implications on every market participant in the igo s region the paper briefly reviews the cm schemes and the associated pricing mechanism used by the igos in five representative schemes these were selected to illustrate the various cm approaches in use england and wales norway sweden pjm and california the authors develop a unified framework for the mathematical representation of the market dispatch and redispatch problems that the igo must solve in cm in these various jurisdictions they use this unified framework to develop meaningful metrics to compare the various cm approaches so as to assess their efficiency and the effectiveness of the market signals provided to the market participants they compare using a small test system side by side the performance of these schemes

contingency constrained reserve requirements in joint energy and ancillary services auction this paper presents a security constrained unit commitment model for energy and ancillary services auction which can be used by an iso to optimize reserve requirements in electricity markets the proposed day ahead algorithm determines reserve requirements by simulating contingencies rather than specifying the requirements as fixed system constraints to address the computational complexity the original auction problem is decomposed into a master problem for solving unit commitment and subproblems for considering network security constraints numerical examples show that the proposed joint auction model can clear energy and ancillary services bids simultaneously while minimizing the total operating cost and satisfying transmission security constraints

a two tier matrix game approach for obtaining joint bidding strategies in ftr and energy markets transmission congestion results in revenue collected from the loads that often exceeds the payment made to the generators the financial transmission right ftr is an instrument that allows the independent system operator iso to redistribute the excess revenue congestion charge among the market participants generators and loads hold ftrs to hedge against congestion charges since the revenues from the ftr and energy markets are interdependent each generator and load must have a joint bidding strategy for ftr and energy markets to maximize its total payoff this paper presents a two tier matrix game model that allows the generators and loads to obtain joint bidding strategies the model also allows the isos and the market designers to assess the impact of various network configurations and rules on market performance e g market power the two tier model considers multiple participants multidimensional bid vectors network contingencies and varying demand we conducted a numerical validation of our model by analyzing the three node network studied by joskow and tirole 2000 additional numerical studies were conducted on a five node network to examine the impact of holding ftrs on the bidding strategies in the energy market and joint payoffs of the participants

the value of asset allocation advice evidence from the economist s quarterly portfolio poll this study analyzes the economic importance of portfolio advice for an investor with an international and multiple asset investment strategy we construct portfolios based upon the asset allocation and security market advice of major international investment bankers and analyze the performance using weight based techniques our results indicate that portfolio advisers are not able to outperform passive benchmarks they do not realize superior performance either through appropriate timing or selection skills apparent market timing skills as measured by the portfolio change measure are to a large extent an artifact caused by serial correlation in the return indices used likewise the apparent short run performance persistence is more due to the serial correlation in returns than to active portfolio selection strategies

decentralized intraday generation scheduling for multiarea power systems via dynamic multiplier based lagrangian relaxation due to day ahead forecast error in load demand and renewable generation there exists inevitable deviation between real time operation and day ahead generation schedules this paper introduces a decentralized multiarea intraday generation scheduling based on nonlinear ac power flow this approach allows for a more reliable and economic operation with the ability to accurately constrain power and voltage securities at a multiarea scale a dynamic multiplier based algorithm is employed for solving the nonlinear multiarea intraday dispatch model which is fully decentralized and thus preserves autonomy for each area the dynamic multiplier based algorithm presents the advantage of accelerated computation compared to conventional static multiplier numerical simulations illustrate the computational performance and practical value of the proposed multiarea intraday generation scheduling framework and dynamic multiplier based algorithm

probabilistic lmp forecasting considering load uncertainty in power market studies the forecast of locational marginal price lmp relies on the load forecasting results from the viewpoint of planning it is well known that short term load forecasting results always carry certain degree of errors mainly due to the random nature of the load at the same time lmp step changes occur at critical load levels clls therefore it is interesting to investigate the impact of load forecasting uncertainty on lmp with the assumption of a certain probability distribution of the actual load this paper proposes the concept of probabilistic lmp and formulates the probability mass function of this random variable the expected value of probabilistic lmp is then derived as well as the lower and upper bound of its sensitivity in addition two useful curves alignment probability of deterministic lmp versus forecasted load and expected value of probabilistic lmp versus forecasted load are presented the first curve is designed to identify the probability that the forecasted price in a deterministic lmp matches the actual price at the forecasted load level the second curve is demonstrated to be smooth and therefore eliminates the step changes in deterministic lmp forecasting this helps planners avoid the possible sharp changes during decision making process the proposed concept and method are illustrated with a modified pjm five bus system and the ieee 118 bus system

data perturbation based sensitivity analysis of real time look ahead economic dispatch in this paper the sensitivity of look ahead economic dispatch in real time power markets with respect to data perturbation is studied in the look ahead dispatch optimization problem a small change in the data that are used for setting the interspatial and temporal equality inequality constraints and the objective function may negatively affect normal operations such as the calculation of real time wholesale electricity prices and operating costs this could lead to more distorted prices and larger operating costs with the look ahead dispatch than with a static dispatch that use data for a single future time we perturb karush kuhn tucker conditions of the look ahead dispatch optimization formulation and then using them derive a linear sensitivity matrix that assesses the impact of data corruption on look ahead dispatch this matrix illustrates the changing optimal solution of look ahead dispatch subject to potential corruption in various types of spatial and temporal data generator s bidding cost coefficients capacity limits for generators and transmission lines ramp rates and the estimate of initial generation output with ramp constraints and multiple time series of the forecast load for the look ahead horizon the results of the simulation are illustrated with numerical examples in the ieee 14 bus system

convergence of volatile power markets with price based demand response price based demand response dr program is a mechanism for encouraging electricity consumers to dynamically manage their energy consumptions in response to time varying electricity prices and thereby reduce peak electricity demands and alleviate the pressure to power systems however it brings additional dynamics and new challenges to the real time supply and demand balance specifically if real time price based dr programs are widely deployed in the future price sensitive dr load levels would constantly change in response to dynamic real time prices which will impact the economic dispatch ed schedule and in turn affect electricity market clearing prices this paper adopts two methods for examining the impacts of different dr price elasticity characteristics and dr participation levels on the convergence of volatile power market a closed loop iterative simulation method and a non iterative method based on the contraction mapping theorem in this paper convergence refers to the fact that load and or price values will finally converge to a fixed point after a finite number of iterations between the ed problem and the price sensitive dr load adjustment five price sensitive dr performance function categories are used to simulate different nonlinear price elasticity characteristics of dr loads numerical studies illustrate how the convergence status of power markets will be affected by the nonlinear price elasticity dr curves the dr penetration levels and the capacity limits of generating units

a joint energy and transmission rights auction proposal and properties an auction based process is proposed that allows power market participants to acquire and reconfigure financial transmission rights the process simultaneously accommodates flowgate and point to point options and obligations along with energy production and consumption futures a sequence of auctions is held during which participants can buy and sell rights which are then settled in a day ahead or real time auction at which time all rights are cashed out by allowing flowgate and point to point obligations and options to be reconfigured and exchanged the market can decide what combination of financial rights are most useful to power generators consumers and traders rights can be specified not only for capacity of individual flowgates but also for more complex transmission constraints such as nomograms under certain conditions we prove that the auction is revenue adequate for the market operator in that payments to rights holders cannot exceed congestion revenues we present a linearized dc auction along with a numerical illustration

using a system model to decompose the effects of influential factors on locational marginal prices locational marginal prices lmps are influenced by various factors such as load uncertainty thermal limit capacity reserve and market power we build a system model to quantitatively analyze the effects of these individual factors and their interactions on the mean and standard deviation of the lmps assuming that the factors are either active or inactive according to the sensitivity analysis results from convex quadratic programming lmps are piecewise linear functions of demand variation which is a key property used in the computation this paper attempts to answer the following types of questions 1 to what extent does market power raise the lmps above the marginal cost 2 what effects will generation or transmission capacity expansion have on relieving high lmps under high demand scenarios an ieee 30 bus test system is used as an example to demonstrate our approach

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

framework for the design and analysis of congestion revenue rights the capability to deal effectively with the uncertainty associated with locational marginal prices lmps in congestion management schemes requires the development of appropriate financial tools congestion revenue rights crr are hedging tools that provide the holder reimbursement of the congestion charges in the day ahead market and thereby provide transmission service customers with price certainty in this paper we construct a framework for the design and analysis of the crr by marrying finance theory notions with salient characteristics of electric power systems and electricity markets the framework consists of three interconnected layers with one layer each to represent the models of the transmission network the commodity markets and the crr financial markets the interaction between the layers is represented as information flows the framework has sufficient scope to allow the analysis of a broad range of problems associated with ensuring price certainty for transmission services the structural modularity of the framework provides the flexibility to analyze issues and design structures for the provision of transmission services in the competitive environment we introduce a new notion of crr payoff parity and a practical pricing scheme which are used as the basis for the design of more liquid crr markets the application of the framework is further illustrated by the analysis of the conditions that guarantee the revenue adequacy for the crr issuer

reactive power constrained opf scheduling with 2 d locational marginal pricing the objective of this paper is to suggest a robust optimal power flow opf framework to perform locational marginal pricing under the scarcity of reactive power the classical opf models employed for market clearing either assume infinite reactive power support or make a fully independent representation of the reactive power load in contrast a potentially more accurate power flow model is adopted in this paper recognizing the dependence of the level of reactive power consumption on the level of active power consumption the relationship is primarily modeled by employing the concept of power factor in addition there can be load requests with different power factors from the same location the corresponding locational marginal prices lmps are found to vary not only spatially but also according to power factors thus a two dimensional lmp variation is finally obtained a consistent definition of financial transmission rights is also provided and the associated lmp decomposition scheme is described the model proposed is studied on the ieee 30 bus system and its distinctive features are noted down and discussed

the equal importance of asset allocation and active management what is the relative importance of asset allocation policy versus active portfolio management in explaining variability in performance considerable confusion surrounds both time series and cross sectional regressions and the importance of asset allocation cross sectional regressions naturally remove market movements therefore the cross sectional results in the literature are equivalent to analyses of excess market returns even though the regressions were performed on total returns in contrast time series analyses of total returns do not naturally remove market movements time series analyses of excess market returns and cross sectional analyses of either total or excess market returns however are consistent with each other with market movements removed asset allocation and active management are equally important in determining portfolio return differences within a peer group finally an examination of period by period cross sectional results reveals why researchers using the same regression technique can get widely different results

on the consistency of backward looking expectations the case of the cobweb in dynamic models of economic fluctuations backward looking expectations with systematic forecasting errors are inconsistent with rational behaviour in non linear dynamic models exhibiting seemingly unpredictable chaotic fluctuations however simple habitual rule of thumb backward looking expectation rules may yield non zero but nevertheless non systematic forecasting errors in a chaotic model expectational forecasting errors may have zero autocorrelations at all lags even for rational agents patterns in these forecasting errors may be very difficult to detect especially in the presence of small noise backward looking expectations are then not necessarily inconsistent with rational behaviour we investigate whether simple expectation schemes such as naive or adaptive expectations can be consistent with rational behaviour in the simplest of all non linear dynamic economic models the non linear cobweb model

imperfect foresight and chaos an example of a self fulfilling mistake abstract we consider an overlapping generations economy with a single production sector and a government first we assume that the households have imperfect foresight in the sense that they cannot distinguish between the trajectories of a deterministic chaotic system and a stochastic process it is shown that mistaking a deterministic chaotic system for a stochastic one is a self fulfilling mistake because the possibility of making this mistake arises only when it is made the unique perfect foresight equilibrium is proved to exhibit simple dynamics for most parameter values finally we show that when agents apply simple econometric models to build their expectations the resulting dynamics resemble the chaotic dynamics of the imperfect foresight equilibrium under certain parameter constellations while they are close to the simple dynamics of the perfect foresight equilibrium for other parameter values

subjective temporary equilibrium abstract this paper introduces within the framework of a simple example the notion of a subjective temporary equilibrium the underlying relation linking forecasts to equilibrium values of the state variable is linear however agents perceive a non linear law that governs the rate of adjustment between successive periods and forecast using linear approximations to the non linear law of motion this is shown to generate a non linear law of motion for the state variable with the feature that the agent s model describes correctly the period wise evolution of the economy the resulting non linear law of motion is referred to as a subjective temporary equilibrium as its specification is determined largely by the subjective beliefs of the agents regarding the dynamics of the system in a subjective equilibrium agents forecasts are generated by taking linear approximations to a correctly specified law of motion and the forecasts may accordingly be interpreted as being boundedly rational in a first order sense there exist specifications that admit the possibility of cyclical behaviour

locational marginal price calculations using the distributed slack power flow formulation in practice locational marginal prices lmps are usually calculated by assembling their three components the reference price the congestion price and the loss price explicit formulas for calculating the three components based on the single slack power flow formulation can be found in the literature this letter presents the formulas for calculating the three components based on a distributed slack power flow formulation