agricultural price instability a survey of competing explanations and remedies there are two explanations for agricultural price dynamics one follows cobweb logic and models fluctuations driven by expectation errors but emphasises that these expectations create complex dynamics and possibly chaos the other stems from the rational expectations tradition of dynamics driven by real shocks the empirical evidence tends to support the latter but is not conclusive the rational expectations model generates an optimal dynamic path from which no improvement can be expected from public intervention however if we take account of all the potential market failures in agricultural markets and especially in developing countries this conclusion might require some qualifications although an appropriate policy design for stability has still to be achieved this paper surveys the positive and normative literature on agricultural prices highlighting empirical evidence and identifying remaining unresolved issues

wheat storage and trade in an efficient global market domestic and international linkages in speculative stockholdings and trade of wheat are analyzed using a dynamic rational expectations model of the world wheat market dominated by the u s and the eu the results demonstrate the importance of endogenizing both storage and trade in studying commodity markets and suggest that past government stockholdings have not followed efficient market outcomes results indicate that elimination of the export enhancement program by the u s and of export restitution payments by the eu are unlikely to have a major impact on wheat exports from the two regions but will save millions of tax dollars in both regions

bi level game approaches for coordination of generation and transmission expansion planning within a market environment the main purpose of this paper is to develop methodologies for simultaneous generation and transmission expansion planning problem of power networks while investigating interactions between these two important sections in the proposed methodologies a transmission operator to operating under different incentives decides about investment in transmission network while anticipating the outcome of a purely competitive electricity market where several rival generation firms complete with each other to determine operating level of their generators amount of their sales and amount of their investment in generation capacity the proposed methodologies rely on bi level programming models whose upper level model represent the problem of investment in transmission by to and the lower level problems represent market outcomes obtained from clearing the market these bi level models are reduced to mixed integer linear and nonlinear programming using the duality theory and karush kuhn tucker kkt optimality conditions the results of the proposed models are analyzed and compared using two illustrative examples

a three level static milp model for generation and transmission expansion planning we present a three level equilibrium model for the expansion of an electric network the lower level model represents the equilibrium of a pool based market the intermediate level represents the nash equilibrium in generation capacity expansion taking into account the outcomes on the spot market and the upper level model represents the anticipation of transmission expansion planning to the investment in generation capacity and the pool based market equilibrium the demand has been considered as exogenous and locational marginal prices are obtained as endogenous variables of the model the three level model is formulated as a mixed integer linear programming milp problem the model is applied to a realistic power system in chile to illustrate the methodology and proper conclusions are reached

liberalized trade and domestic price stability the case of rice and wheat in india abstract this paper analyzes the effects of liberalizing foodgrain trade on domestic price stability using a multi market equilibrium model in which the direction of trade is determined endogenously and world prices are sensitive to the amount traded by india simulation results demonstrate that contrary to popular belief freeing of trade by india leads to greater domestic price stability even though world prices are more volatile freeing of trade by india also leads to higher world price stability under liberalized trade variable levies subsidies are more effective in stabilizing domestic prices compared to buffer stocks it is therefore in india s interest to argue for non zero binding on import tariffs and export subsidies at the wto negotiations

network planning in unbundled power systems in this paper a new approach for network planning in unbundled power systems is presented the approach takes into account the desires of demand customers power producers system operator network owner s and regulator in network planning competition reliability flexibility of operation transmission expansion cost and environmental impacts are used as planning criteria in order to consider the importance degrees of stakeholders and planning criteria in network planning first importance degrees of stakeholders and planning criteria are determined by a presented new method then importance degrees of stakeholders and planning criteria are aggregated with appropriateness degrees of expansion plans to compute a fuzzy index for measuring the goodness of expansion plans the final plan is selected using the presented fuzzy risk assessment method the approach is applied to an eight bus test system

impact of forecast errors on expansion planning of power systems with a renewables target abstract this paper analyzes the impact of production forecast errors on the expansion planning of a power system and investigates the influence of market design to facilitate the integration of renewable generation for this purpose we propose a programming modeling framework to determine the generation and transmission expansion plan that minimizes system wide investment and operating costs while ensuring a given share of renewable generation in the electricity supply unlike existing ones this framework includes both a day ahead and a balancing market so as to capture the impact of both production forecasts and the associated prediction errors within this framework we consider two paradigmatic market designs that essentially differ in whether the day ahead generation schedule and the subsequent balancing re dispatch are co optimized or not the main features and results of the model set ups are discussed using an illustrative four node example and a more realistic 24 node case study

transmission expansion planning in electricity markets this paper presents a mixed integer linear programming lp formulation for the long term transmission expansion planning problem in a competitive pool based electricity market to achieve optimal expansion planning while modeling market functioning we define a number of scenarios based on the future demand in the system and we simulate the maximization of the aggregate social welfare investment and operating costs transmission losses and generator offers and demand bids are considered we propose to use a set of metrics to rate the effect of the expansion on the generators demands and the system as a whole the proposed model is applied to the garver six bus system and to the ieee 24 bus reliability test system simulation results can be interpreted in economic terms based on the values of the metrics obtained for different scenarios parameters and topologies

sequential coordination of transmission expansion planning with strategic generation investments this paper proposes mathematical models for sequential coordination of transmission expansion planning with strategic generation investments the proactive and reactive coordinations are modeled and studied the interaction between transmission company transco and strategic generation companies gencos is modeled using the sequential move game this is while the interaction between the strategic gencos is modeled as a simultaneous move game in the proactive coordination the transco expands its future transmission capacities taking into account the strategic investments by gencos in the reactive coordination strategic gencos move first and expand their future generation capacities and then transco expands the transmission capacity the proactive coordination is modeled as a mixed integer bilevel linear program miblp and the reactive coordination is modeled as a mixed integer linear program milp the miblp has binary variables in both upper and lower levels the moore bard algorithm is parallelized and used to solve the miblp the mathematical models and the parallelized moore bard algorithm are tested on 3 bus and 6 bus example systems and the modified ieee rts96 also the ieee 118 bus test system is studied using a heuristic version of the moore bard algorithm

congestion driven transmission expansion in competitive power markets a framework for transmission planning in a deregulated power market environment is discussed the level of congestion in the network is utilized as the driving signal for the need of network expansion a compromise between the congestion cost and the investment cost is used to determine the optimal expansion scheme the long term network expansion problem is formed as the decoupled combination of 1 the master problem minimization of investment costs subject to investment constraints and the benders cuts generated by the operational problem power pool and 2 the operational problem whose solution provides congestion details and associated multipliers a proper power pool model is developed and solved for congestion cost congestion revenue and transmission shadow prices linear programming is utilized to solve the investment subproblem while the quadratic programming technique has been used to solve the operational problem the algorithm has been developed for the complete planning process which provides the expansion schemes for the planning horizon the technique has been applied to illustrate the network planning study for a modified ieee 24 bus test system

the economics of planning electricity transmission to accommodate renewables using two stage optimisation to evaluate flexibility and the cost of disregarding uncertainty abstract aggressive development of renewable electricity sources will require significant expansions in transmission infrastructure we present a stochastic two stage optimisation model that captures the multistage nature of transmission planning under uncertainty and use it to evaluate interregional grid reinforcements in great britain gb in our model a proactive transmission planner makes investment decisions in two time periods each time followed by a market response uncertainty is represented by economic technology and regulatory scenarios and first stage investments must be made before it is known which scenario will occur the model allows us to identify expected cost minimising first stage investments as well as estimate the value of information the cost of ignoring uncertainty and the value of flexibility our results show that ignoring risk in planning transmission for renewables has quantifiable economic consequences and that considering uncertainty can yield decisions that have lower expected costs than traditional deterministic planning methods in the gb case the value of information and cost of disregarding uncertainty in transmission planning were of the same order of magnitude approximately 100 m in present worth terms further the best plan under a risk neutral decision criterion can differ from the best under risk aversion finally a traditional sensitivity analysis based robustness analysis also yields different results than the stochastic model although the former s expected cost is not much higher

price stabilization using buffer stocks abstract the price stabilization problem is stated and solved for a nonlinear cobweb model with government stocks it is shown that if the storage capacity for the commodity is sufficiently large then there exists a simple stabilization policy called the keep supply at equilibrium kse policy such that the equilibrium price is a global attractor for the corresponding closed loop system in addition it is shown that if the government approximates the equilibrium supply with the average supply stabilization is guaranteed we refer to this policy as keep supply at average ksa

a bilevel approach to transmission expansion planning within a market environment we present a bilevel model for transmission expansion planning within a market environment where producers and consumers trade freely electric energy through a pool the target of the transmission planner modeled through the upper level problem is to minimize network investment cost while facilitating energy trading this upper level problem is constrained by a collection of lower level market clearing problems representing pool trading and whose individual objective functions correspond to social welfare using the duality theory the proposed bilevel model is recast as a mixed integer linear programming problem which is solvable using branch and cut solvers detailed results from an illustrative example and a case study are presented and discussed finally some relevant conclusions are drawn

food security and storage in the middle east and north africa in times of highly volatile commodity markets governments often try to protect their populations from rapidly rising food prices which can be particularly harsh for the poor a potential solution for food deficit countries is to hold strategic reserves which can be called on when international prices spike but how large should strategic stockpiles be this paper develops a dynamic storage model for wheat in the middle east and north africa mena region where imported wheat dominates the average diet the paper uses the model to analyze a strategy that sets aside wheat stockpiles which can be used when needed to keep domestic prices below a targeted price this paper shows that if the target is set high and reserves are adequate the strategy can be effective and robust contrary to most interventions strategic storage policies are counter cyclical and when the importing region is sufficiently large a regional policy can smooth global prices this paper shows that this is the case for the mena region nevertheless the policy is more costly than the pro cyclical policy of a targeted intervention that directly offsets high prices with a subsidy similar to food stamps

co operation and the urban environment an exploration many urban environmental problems such as littering of streets arise from the open access character of the resource concerned and can be analysed in the framework of co operation studies in the context of rural commons have indicated that though seeming to be violating a narrow definition of rationality people do cooperate this paper attempts to explore some issues in the context of the urban environment focusing on solid waste management in madras india and a co operation based institution called exnora a number of hypotheses on the conditions affecting co operation are examined while group size may be relevant for costs it does not have any impact on co operation the management style of committees and economies of scope seem to be important

optimal food price stabilization in a small open developing country in poor countries most governments implement policies aiming to stabilize the prices of staple foods which often include storage and trade measures insulating their domestic market from the world market it is of crucial importance to understand the precise motivations and efficiency of those interventions because they can have consequences worldwide this paper addresses those issues by analyzing the case of a small open developing country confronted by shocks to both the crop yield and foreign price in this model government interventions may be justified by the lack of an insurance market for food prices considering this market imperfection the authors design optimal public interventions through trade and storage policies they show that an optimal trade policy largely consists of subsidizing imports and taxing exports which benefits consumers at the expense of producers import subsidies alleviate the non negativity of food storage in other words when stocks are exhausted subsidizing imports prevents domestic price spikes one striking result an optimal storage policy on its own is detrimental to consumers since its stabilizing benefits leak into the world market and it raises the average domestic price by contrast an optimal combination of storage and trade policies results in a powerful stabilizing effect for domestic food prices

can top down and bottom up be reconciled electoral competition and service delivery in malaysia summary top down versus bottom up is one of development s enduring tensions not least in public service delivery in malaysia public services have traditionally been animated from the top down bottom up forces in civil society have strengthened recently but so too have top down forces and their impact on public services is greater malaysia s experience suggests that where electoral competition gives politicians an incentive to respond to voters service preferences top down initiatives have the greater potential for large scale social change participatory initiatives will be most effective when they play a supplementary role

transmission and wind power investment this paper jointly considers wind power investment and transmission reinforcement the proposed model is a mathematical program with equilibrium constraints mpec that seeks to identify the optimal wind projects to be developed and the required network reinforcements under the transmission system operator perspective this mpec seeks to minimize consumer payments and is constrained by investment conditions and the equilibria of the market under different operating conditions an array of subsidies is considered to promote independent wind power investment an example and two case studies illustrate the characteristics of the proposed model

probabilistic midterm transmission planning in a liberalized market this paper shows a midterm transmission planning methodology for liberalized electricity markets this methodology evaluates expansions and reinforcements using a transmission adequacy linear programming model this type of modeling solves efficiently taking into account power exchange deviations n 1 network preventive adequacy level and nonsupply demand statistical results are obtained sampling power exchange scenarios and computing transmission investment sensitivities after each sample of generation and consumption bidding and generator and circuit failures means ranges and confidence intervals of transmission investment sensitivities are updated these sensitivities are computed using dual variables and reduced costs of the transmission adequacy model this statistical sensitivity information and additional information are evaluated jointly using multicriteria decision theory an extended garver s six bus and the spanish system cases are analyzed

market based coordination of transmission and generation capacity planning we propose an iso model for coordinating transmission expansion planning with competitive generation capacity planning in electricity markets the purpose of the model is a holistic simulation of generation and transmission capacity expansion in the market environment the solution represents an iterative process for simulating the interactions among gencos transcos and the iso which might be terminated by the iso based on a pre specified stopping criterion the proposed model adopts a joint energy and transmission auction market and a capacity mechanism the joint auction market enables competition to occur among generation and transmission resources the capacity mechanism offers incentives for market participant investments that reflect the locational values of additional capacity transmission capacity expansion decisions are made by merchant transmission lines that recover their capacity investments through transmission marginal pricing and capacity payments transmission network security is reflected in the proposed competitive resource planning model the examples illustrate a coordinated planning of generation and transmission in restructured power systems

accountability in public services exit voice and control abstract this paper argues that the positive impact of public accountability on public service performance and governance in general can be augmented by moving away from an exclusive reliance on control mechanisms such as hierarchical monitoring and use of organizational incentives to a system that uses exit or voice mechanisms in conjunction with control whether the public will resort to exit or voice will depend on the relative costs associated with these options and the expected value to them of the performance improvement resulting from their use in a specific context public services can be categorized in terms of the exit and voice potential they afford the public by reference to certain barriers and characteristics the paper provides a framework for the analysis of the features and barriers of public services and of the publics involved that can be used to predict the potential for the use of exit and voice in specific service contexts a menu of options for improving public accountability through the use of exit and voice mechanisms and their policy implications are also presented

trade liberalization and domestic price instability in an agricultural commodity market price instability appears to be a feature of many agricultural markets in turn reduction of instability is a key motive for intervention in industrialized countries where trade instruments are used for this purpose they can sever the link between domestic and international prices the consequences of market insulation for price variability are examined a simple partial equilibrium model is developed and its predictions are examined against the experience of liberalization in the british main crop potato market

flexible transmission expansion planning with uncertainties in an electricity market deregulation of the electric power industry has introduced new uncertainties for market participants and made planning of transmission expansion more difficult more flexible transmission expansion plans are needed to cope with the increased risks in this paper a novel planning approach is proposed to meet the above challenge in our approach the planning process is modeled as a mixed integer nonlinear programming minlp problem so that conflicting objectives can be optimized simultaneously to minimize planning risks our method identifies several scenarios based on statistics and expert knowledge the most flexible expansion plan is selected as the plan that has least adaptation cost the proposed method is tested with the ieee 14 bus system promising results are obtained to demonstrate the effectiveness of our method

what are the benefits of co optimizing transmission and generation investment eastern interconnection case study transmission planning has traditionally followed a generation first or reactive logic in which network reinforcements are planned to accommodate assumed generation build outs the emergence of renewables has revealed deficiencies in this approach in that it ignores the interdependence of transmission and generation investments for instance grid investments can provide access to higher quality renewables and thus affect plant siting disregarding this complementarity increases costs in theory this can be corrected by proactive transmission planning which anticipates how generation investment responds by co optimizing transmission and generation investments we evaluate the potential usefulness of co optimization by applying a mixed integer linear programming formulation to a 24 bus stakeholder developed representation of the u s eastern interconnection we estimate cost savings from co optimization compared to both reactive planning and an approach that iterates between generation and transmission investment optimization these savings turn out to be comparable in magnitude to the amount of incremental transmission investment we also evaluate three congestion metrics as screens for reducing the number of candidate transmission investments they each improve solution times but the estimated potential benefit metric is much more effective in identifying cost effective lines than the others

transmission expansion in an oligopoly considering generation investment equilibrium abstract transmission expansion planning tep is a sophisticated decision making problem especially in an oligopolistic electricity market in which a number of strategic price maker producers compete together a transmission system planner who is in charge of making tep decisions requires considering the future generation investment actions however in such an oligopolistic market each producer makes its own strategic generation investment decisions this motivates the transmission system planner to consider the generation investment decision making problem of all producers within its tep model the strategic generation investment problem of each producer can be represented by a complementarity bi level model the joint consideration of all bi level models one per producer characterizes the generation investment equilibrium that identifies the future evolution of generation investment in the market this paper proposes a tri level tep decision making model to be solved by the transmission system planner whose objective is to maximize the social welfare of the market minus the expansion costs and whose constraints are the transmission expansion limits as well as the generation investment equilibrium problem this model is then recast as a mixed integer linear programming problem and solved numerical results from an illustrative example and a case study based on the ieee 14 bus test system demonstrate the usefulness of the proposed approach

robust transmission planning under uncertain generation investment and retirement transmission planning is typically faced with a wide range of uncertainty including growth in demand renewable energy generation and fuel price the restructuring of the electric power industry the drive for energy independence and the push for a cleaner environment have led to additional sources of uncertainty in all aspects of power system operations and planning the more decentralized decision making implicates uncertainty in future generation investment and retirement of existing units such uncertainties are among the biggest challenges in transmission planning in power systems however existing approaches in the literature do not fully address this problem in this paper we construct a new robust transmission planning model representing generation investment and retirement uncertainty more realistically to improve the quantification and visualization of uncertainty and the impacts of environmental policies with this model we can manage the impacts of uncertainty in the time the size and the location of candidate generation additions as well as the retirement of units the corresponding algorithm we develop takes advantage of the structural characteristics of the model so as to obtain a computationally efficient solution methodology we present an extensive numerical study on the wecc 240 bus system and illustrate the effectiveness of our approach

a theory of competition among pressure groups for political influence this paper presents a theory of competition among pressure groups for political influence political equilibrium depends on the efficiency of each group in producing pressure the effect of additional pressure on their influence the number of persons in different groups and the deadweight cost of taxes and subsidies an increase in deadweight costs discourages pressure by subsidized groups and encourages pressure by taxpayers this analysis unifies the view that governments correct market failures with the view that they favor the politically powerful both are produced by the competition for political favors

can information about local government performance induce civic participation evidence from the philippines abstract the question of whether people are motivated to engage in civic activities once informed of their local government s performance is relevant to many developing countries that adopted decentralisation applying propensity score matching technique on a unique household level dataset from the philippines it is found that the knowledge of an index of local government performance has positive and statistically significant effects on the likelihood of membership in local organisations and participation in local projects thus the results support policies for greater transparency in local governance to deepen citizenship

energy governance transnational rules and the resource curse exploring the effectiveness of the extractive industries transparency initiative eiti transnational standards for disclosure have become a defining feature of global governance and sound economic development yet little is known about their effectiveness this study statistically explores the efficacy of such standards for the important case of the extractive industries transparency initiative eiti an international non governmental organization which maintains a voluntary standard for revenue transparency in the extractive industries as of november 2015 31 countries were eiti compliant and another 49 were eiti candidates in total 49 countries had disclosed payments and revenues worth some 1 67 trillion in more than 200 eiti reports and over 90 major companies involved in oil gas and mining are committed to supporting the eiti the eiti has also received support from 84 global investment institutions that collectively manage about 16 trillion in energy infrastructural assets moreover the european union african union g8 and g20 and the united nations have all endorsed the eiti this article provides the first broad empirical examination of the eiti s effectiveness in improving governance and economic development outcomes in its member countries using non parametric tests regression analysis and data from the world bank we analyze the performance of the first 16 countries to attain eiti compliance status over the period of 1996 2014 we find interestingly that in most metrics eiti countries do not perform better during eiti compliance than before it and that they do not outperform other countries we postulate four possible explanations behind the relative weakness of the eiti a limited mandate its voluntary nature stakeholder resistance and dependence on strong civil society

economic criteria for planning transmission investment in restructured electricity markets from an economic perspective a common criterion for assessing the merits of a transmission investment is its impacts on social welfare the underlying assumption in using this criterion is that side payments may be used to distribute the social gains among all market players in reality however since the impacts of an electricity transmission project on different players may vary such side payments are rather difficult to implement this paper focuses on different economic criteria that should be considered when planning electricity transmission investments we propose an electricity transmission investment assessment methodology that is capable of evaluating the economic impacts on the various effected stakeholders and account for strategic responses that could enhance or impede the investment s objectives we formulate transmission planning as an optimization problem under alternative conflicting objectives and investigate the policy implications of divergent expansion plans resulting from the planner s level of anticipation of strategic responses we find that optimal transmission expansion plans may be very sensitive to supply and demand parameters we also show that the transmission investments have significant distributional impact creating acute conflicts of interests among market participants we use a 32 bus representation of the main chilean grid to illustrate our results

a tri level model of centralized transmission and decentralized generation expansion planning for an electricity market part ii we study a tri level integrated transmission and generation expansion planning problem in a deregulated power market environment the collection of bi level sub problems in the lower two levels is an equilibrium problem with equilibrium constraints epec that can be approached by either the diagonalization method dm or a complementarity problem cp reformulation this paper is a continuation of its part i in which a hybrid iterative algorithm is proposed to solve the tri level problem by iteratively applying the cp reformulation of the tri level problem to propose solutions and evaluating them in the epec sub problem by dm it focuses on the numerical results obtained by the hybrid algorithm for a 6 bus system a modified ieee 30 bus system and an ieee 118 bus system in the numerical instances the approximate nash equilibrium point for the sub problem can be verified by examining local concavity

a transmission planning framework considering future generation expansions in electricity markets this paper proposes a transmission planning framework in a market environment in which only the generation sector is deregulated the proposed framework is based on modeling generation companies gencos strategic behavior and anticipating their expansion patterns from the viewpoint of a transmission system planner the transmission expansion planning problem in this paper is modeled as a four level optimization problem a solution method based on agent based systems and search based optimization techniques is proposed to determine the optimal transmission expansion plan

congestion driven transmission planning considering the impact of generator expansion this paper presents a multi year transmission expansion planning tep model which considers the transmission congestion and the impact of generation investment cost in the planning horizon the benders decomposition approach is utilized which decomposes tep into a master problem and two subproblems representing security and optimal operation the operation cost due to congestion occ is considered in the proposed model given that the congestion level is a proper criterion for measuring the degree of competitiveness in an electricity market the model evaluates sensitivity of the optimal tep to congestion level planning horizon and financial constraints regulators can utilize the proposed results to provide long term tep to market players and to develop incentive mechanisms to trigger generation investments the proposed approach is applied to a hypothetical system and turkish power system

coordination of generation and transmission development through generation transmission charges a game theoretical approach transmission charges aim to recover the cost of transmission network investments and provide efficient locational signals to new generators in this paper we investigate the effect of these charges on the development of new generation capacities in the system generation expansion planning is decided by strategic generation planners sgps trying to maximize their profits while transmission line investments are planned by a central planner and regulatory body aimed at minimizing the overall operation and network investment costs of the system regulatory transmission charges rtcs are calculated according to the marginal responsibility of generation investment on transmission network investment costs an iterative algorithm is proposed to model the interaction taking place between the central planner and sgps the developed methodology is applied to a 2 node illustrative example and the ieee rts96 and effects of rtcs on investment decisions of sgps are analyzed