medium term power planning with bilateral contracts this paper addresses the optimal management of hydropower resources on medium term the objective is to maximize the expected revenue of a producer and the decision variables are generation and forward contracts in each period for each scenario stochastic linear and nonlinear programming has been used as a framework for modeling and solution results are exposited for a norwegian power producer participating in nord pool the nordic power exchange

the renewable energy growth and environmental kuznets curve in turkey an ardl approach abstract this study examines the potential of renewable energy sources in reducing the impact of ghg emissions in turkey using autoregressive distributed lag ardl approach the relationship between co 2 emissions electricity generated using renewables and gdp in turkey has been investigated during 1961 2010 moreover the validity of environmental kuznets curve ekc hypothesis has been tested model results show that the coefficient of electricity production from renewable sources hydro power excluded with respect to co 2 emissions is negative and significant in the long run although this effect is positive and statistically significant in the short run since the ecm term is 0 82 it becomes negative around 1 year this means that renewable electricity production will contribute to environmental enhancement with a one year lag our results also suggest a u shaped ekc relationship between per capita ghgs and income estimations from a long run regression show that although the peak point of gdp per capita has been calculated to be 9920 us dollars this turning point was outside of the observed sample period therefore ghg emissions start to decrease with an increase in per capita gdp in the following years model research implies the potential and the importance of renewable energy sources in controlling of emissions in turkey

co2 emissions energy consumption and economic growth in bric countries abstract this paper examines dynamic causal relationships between pollutant emissions energy consumption and output for a panel of bric countries over the period 1971 2005 except for russia 1990 2005 in long run equilibrium energy consumption has a positive and statistically significant impact on emissions while real output exhibits the inverted u shape pattern associated with the environmental kuznets curve ekc hypothesis with the threshold income of 5 393 in logarithms in the short term changes in emissions are driven mostly by the error correction term and short term energy consumption shocks as opposed to short term output shocks for each country short term deviations from the long term equilibrium take from 0 770 years russia to 5 848 years brazil to correct the panel causality results indicate there are energy consumption emissions bidirectional strong causality and energy consumption output bidirectional long run causality along with unidirectional both strong and short run causalities from emissions and energy consumption respectively to output overall in order to reduce emissions and not to adversely affect economic growth increasing both energy supply investment and energy efficiency and stepping up energy conservation policies to reduce unnecessary wastage of energy can be initiated for energy dependent bric countries

a semi parametric panel data analysis on the urbanization carbon emissions nexus for oecd countries abstract this study takes a fresh look at the presence of an urbanization carbon emissions environmental kuznets curve for a panel of the organization for economic co operation and development oecd countries from 1960 to 2010 using a recently developed semi parametric panel fixed effects regression model through incorporating a quadratic term for the urbanization variable into the stochastic impacts by regression on population affluence and technology model our analysis represents one of the first oecd studies aimed at determining the effect of urbanization on carbon emissions and identifying the relationship between these two variables compared with parametric panel fixed effects regression more robust results from the recently developed method revealed that energy intensity and per capita gdp had clear effects on per capita carbon emissions urbanization also significantly contributed to changes in per capita carbon emissions we also found strong evidence for an inverse u shaped curve relationship between urbanization and carbon emissions verifying the environmental kuznets curve hypothesis these findings advance the emerging consensus on the urbanization carbon emissions nexus also the novel model used combined with our estimation method can be readily extended to cover other regions for investigating the relationship between development and environmental pollution

strategic bidding of a hydropower producer under uncertainty modified benders approach this paper proposes a stochastic bilevel program for strategic bidding of a hydropower producer the price quantity and ramp rate bids are considered the uncertainty of wind power generation variation of inflows for the hydropower producer and demand variability are modeled through the moment matching scenario generation technique using discretization the stochastic bilevel program is reformulated as a stochastic mixed integer linear program milp with disjunctive constraints we propose a modified benders decomposition algorithm mbda which fully exploits the disjunctive structure of reformatted milp model more importantly the mbda does not require optimal tuning of disjunctive parameters and it can be efficiently parallelized through an illustrative 5 node example we identify possible strategies specific to a hydropower producer for maximizing profit which in turn leads to market insights we also use the ieee 24 node 118 node and 300 node case studies to show how our parallelized mbda outperforms the standard benders decomposition algorithm the parallelized mbda is also compared to the state of the art cplex solver

optimized offers for cascaded hydroelectric generators in a market with centralized dispatch we examine the problem of a generator offering generation and ancillary services from a set of cascaded hydroelectric units to a centrally dispatched market that does not account for watershed constraints by modeling the least cost dispatch problem and computing the resulting schedules and market prices we formulate a stochastic bilevel optimization problem that maximizes the generator s expected profits under different demand and supply realizations to account for potential infeasibilities in the resulting hydroelectric dispatch we include penalties in the generator s objective function we propose a simple technique that replaces the lower level dispatch problem with its linearized karush kuhn tucker optimality conditions to convert the problem to a single level mixed integer program we use two numerical case studies based on actual river systems to demonstrate the benefits of the proposed model

is there an environmental kuznets curve for south africa a co summability approach using a century of data abstract there exists a huge international literature on the so called environmental kuznets curve ekc hypothesis which in turn postulates an inverted u shaped relationship between environmental pollutants and output the empirical literature on ekc has mainly used test for cointegration based on polynomial relationships between pollution and income motivated by the fact that measured in per capita co 2 equivalent emissions south africa is the world s most carbon intensive non oil producing developing country this paper aims to test the validity of the ekc for south africa for this purpose we use a century of data 1911 2010 to capture the process of development better compared to short sample based research and the concept of co summability which is designed to analyze non linear long run relations among persistent processes our results however provide no support of the ekc for south africa both for the full sample and sub samples determined by tests of structural breaks implying that to reduce emissions without sacrificing growth policies should be aimed at promoting energy efficiency

optimal involvement in futures markets of a power producer this paper addresses the optimal involvement in a futures electricity market of a power producer to hedge against the risk of pool price volatility the considered trading horizon spans one whole year recognizing the highly uncertain nature of future pool prices a stochastic programming framework with recourse is used to model this decision making problem the resulting problem is a large scale mixed integer linear programming problem scenario reduction techniques are used to make this problem tractable risk is properly modeled using the cvar methodology results from a realistic case study are provided and analyzed some conclusions are finally drawn

does economic integration damage or benefit the environment africa s experience abstract the leaders of african nations have committed to the establishment of the continental free trade area cfta over the coming years improved links among the african nations via increased intra regional trade have been considered as an essential mechanism to produce desired growth run overs and to support regional economic improvement however remarkable theoretical and empirical evidence has shown that increased trade might damage the environment and therefore may hinder the effort towards sustainable development and poverty reduction on the continent the present paper seeks to investigate and test the impact of intra africa trade using two measurements of environmental pollutants namely co2 and mp10 whilst integrating economic growth and energy consumption the study used a panel dataset regarding 46 african countries over the period 1990 2017 to carry out the empirical analysis the latest panel estimation techniques were employed more specifically and for the urbaneness purpose we employed a parametric technique which is dynamic ols and a non parametric approach which is fmols the results of both methods suggested that intra africa trade improved environmental quality on the continent in addition the results confirmed the presence of the environmental kuznets curve ekc hypothesis the findings also indicated that whilst the consumption of energy played a vital role in the deterioration of the environment its impact remained marginal overall the results implied that intra regional trade and the environment quality were mutually supportive in africa

economic obstacles to expanding intra african trade abstract the paper extends the gravity model to examine the impact of infrastructure availability economic policy and internal political tensions on intra african trade to highlight specific obstacles hampering such a trade bilateral trade between africa and developed countries is also analyzed the results show that besides traditional gravity variables poor infrastructure economic policy mismanagement and internal political tensions have a negative impact on trade among african countries except for political tensions the identified obstacles are specific to intra african trade since they have no impact on african trade with developed countries

operating policies for energy generation and revenue management in single reservoir hydropower systems abstract we study the reservoir management problem in hydropower plants and propose operating policies to maximize the average annual energy generation or the average annual revenue under revenue maximization our policies allow for short term electricity price variations to be incorporated into the long term plan first we provide a detailed review of hydropower plant operation focusing on implicit stochastic optimization approaches and integration of energy price variations in reservoir management then we explain non linear programming models that we developed for obtaining operating policies with different characteristics we evaluate and compare the operating policies through a case study policies characterized by dynamic end of month storage levels are shown to perform much better than the policy with an optimal static end of month storage level and it has been further shown that the dynamic policies perform quite close to the theoretical upper bound finally we show that maximizing the average annual energy and maximizing the average annual revenue objectives yield considerably different operating policies and using one policy in place of the other may result in significant loss of benefit or resource

nash equilibrium in strategic bidding a binary expansion approach this paper presents a mixed integer linear programming solution approach for the equilibrium problem with equilibrium constraints epec problem of finding the nash equilibrium ne in strategic bidding in short term electricity markets a binary expansion be scheme is used to transform the nonlinear nonconvex ne problem into a mixed integer linear problem milp which can be solved by commercially available computational systems the be scheme can be applicable to cournot bertrand or joint price quantity bidding models the approach is illustrated in case studies with configurations derived from the 95 gw brazilian system including unit commitment decisions to the price maker agents

non renewable and renewable energy consumption and co2 emissions in oecd countries a comparative analysis abstract this paper attempts to explore the determinants of co 2 emissions using the stirpat model and data from 1980 to 2011 for oecd countries the empirical results show that non renewable energy consumption increases co 2 emissions whereas renewable energy consumption decreases co 2 emissions further the results support the existence of an environmental kuznets curve between urbanisation and co 2 emissions implying that at higher levels of urbanisation the environmental impact decreases therefore the overall evidence suggests that policy makers should focus on urban planning as well as clean energy development to make substantial contributions to both reducing non renewable energy use and mitigating climate change

investigation of the environmental kuznets curve for carbon emissions in malaysia do foreign direct investment and trade matter abstract environmental degradation has become a central issue of discussion among the economists and environmentalists in view of malaysia s position as one of the main contributors to co2 emissions in asia and its status as a fast growing economy it is vital therefore to conduct a study to identify the relationship between economic growth and co2 emissions for malaysia this study attempts to examine empirically the environmental kuznets curve hypothesis for malaysia in the presence of foreign direct investment and trade openness both in the short and long run for the period 1970 to 2008 the bounds testing approach and granger causality methodology are applied to test the interrelationships of the variables the results of our study indicate that the inverted u shaped relationship does exist between economic growth and co2 emission in both the short and long run for malaysia after controlling for two additional explanatory variables namely fdi and trade importantly the results of the study also provide some crucial policy recommendations to the policy makers

does trade openness improve environmental quality the literature on trade openness economic development and the environment is largely inconclusive about the environmental consequences of trade this study treats trade and income as endogenous and estimates the overall impact of trade openness on environmental quality using the instrumental variables technique we find that whether or not trade has a beneficial effect on the environment varies depending on the pollutant and the country trade is found to benefit the environment in oecd countries it has detrimental effects however on sulfur dioxide so2 and carbon dioxide co2 emissions in non oecd countries although it does lower biochemical oxygen demand bod emissions in these countries we also find the impact is large in the long term after the dynamic adjustment process although it is small in the short term

a review on risk constrained hydropower scheduling in deregulated power market in deregulated power market hydro producer has in principle no other objective than to produce electricity and sell with maximum profit with lower market risk attention must focus on profit uncertainty caused by uncertainty in spot prices and reservoir inflow the purpose of this review is to assess the state of the art in hydropower operations considering profit risk under uncertainty and consider future directions for additional research and application physical and financial tools to hedge risk in bilateral market and risk assessment methods are all discussed in detail furthermore production resources can also be used to manage risk to a certain extent this concept when be integrated with variety of risk management methods under stochastic optimal framework has operational significance for hydro producer participating in electricity market

a note on the integrability of partial equilibrium measures of the welfare costs of inflation multidimensional measures of the welfare costs of inflation have been employed in the literature without an explicit concern of how the demand for the respective monetary assets are generated and without an investigation of the respective integrability conditions this note establishes conditions under which such welfare measures are well defined

weekly self scheduling forward contracting and pool involvement for an electricity producer an adaptive robust optimization approach abstract this paper addresses the optimization under uncertainty of the self scheduling forward contracting and pool involvement of an electricity producer operating a mixed power generation station which combines thermal hydro and wind sources and uses a two stage adaptive robust optimization approach in this problem the wind power production and the electricity pool price are considered to be uncertain and are described by uncertainty convex sets to solve this problem two variants of a constraint generation algorithm are proposed and their application and characteristics discussed both algorithms are used to solve two case studies based on two producers each operating equivalent generation units differing only in the thermal units characteristics their market strategies are investigated for three different scenarios corresponding to as many instances of electricity price forecasts the effect of the producers approach whether conservative or more risk prone is also investigated by solving each instance for multiple values of the so called budget parameter it was possible to conclude that this parameter influences markedly the producers strategy in terms of scheduling profit forward contracting and pool involvement these findings are presented and analyzed in detail and an attempted rationale is proposed to explain the less intuitive outcomes regarding the computational results these show that for some instances the two variants of the algorithms have a similar performance while for a particular subset of them one variant has a clear superiority

dynamic modeling of causal relationship between energy consumption co2 emissions and economic growth in india abstract the paper investigates the causality relationships among energy consumption carbon dioxide co2 emissions and income in india using a dynamic modeling approach the paper also utilises an innovation accounting method to investigate profiles of the macroeconomic variables persisting from an unanticipated shock in innovation our results provide evidence of the existence of bi directional granger causality between energy consumption and co2 emissions in the long run but neither co2 emissions nor energy consumption causes movements in real income there is no causality relationship between energy consumption and income in any direction in the long run implying that india could follow energy conservation and efficiency improvement policies without impeding economic growth this will allow india to reduce co2 emissions without affecting its economic growth and contribute significantly towards combating global warming as well

a medium term integrated risk management model for a hydrothermal generation company this paper presents a methodology to manage the market risk faced by a hydrothermal generation company in the medium term one year this risk is due to uncertainty in fuel prices power demand water inflows and electricity prices the proposed methodology includes three steps the generation of scenarios for these random parameters the approximation of these scenarios by a multivariate scenario tree and the optimization of the company s operational and financial hedging decisions under a stochastic programming framework the optimization model permits the representation of a diversified generation portfolio and measures risk exposure by means of conditional value at risk a realistic numerical example is solved to illustrate the possibilities of our approach

simulating oligopolistic pool based electricity markets a multiperiod approach this paper simulates a pool based electricity market and identifies equilibrium patterns a multiperiod framework that requires the use of continuous and binary variables is considered producers can be either price takers or price makers although price makers and their behavior characterize the market the elasticity of the loads is modeled through piecewise constant price demand curves the market operator uses a detailed network constrained market clearing auction that results in hourly market clearing prices the behavior of the market participants and the market itself are characterized through a repetitive simulation procedure the tool presented in this paper is particularly useful for the market regulator that may use it to monitor the market and to identify the exercise of market power by producers results from a realistic case study are presented and discussed

risk constrained scheduling and offering strategies of a price maker hydro producer under uncertainty this paper presents a stochastic mixed integer linear programming smilp approach to maximize total expected profit of one price maker hydro producer in a pool based electricity market head dependence commitment decisions discharge ramping startup costs and forbidden zones are all effectively handled in our approach uncertainty about the competitors offers is adequately represented by residual demand curves rdcs scenarios the management of risk is suitably addressed by conditional value at risk cvar to provide the efficient frontier i e the solutions set for which the expected profit may not be augmented without enlarging the variance of profit appropriate offering strategies to the pool are also developed consisting of supply functions built for different risk levels a representative cascaded hydro system with 7 reservoirs is considered to analyze and compare risk neutral versus risk averse results

strategic bidding under uncertainty a binary expansion approach this work presents a binary expansion be solution approach to the problem of strategic bidding under uncertainty in short term electricity markets the be scheme is used to transform the products of variables in the nonlinear bidding problem into a mixed integer linear programming formulation which can be solved by commercially available computational systems the be scheme is applicable to pure price pure quantity or joint price quantity bidding models it is also possible to represent transmission networks uncertainties scenarios for price quantity plant availability and load financial instruments capacity reinforcement decisions and unit commitment the application of the methodology is illustrated in case studies with configurations derived from the 80 gw brazilian system

price maker self scheduling in a pool based electricity market a mixed integer lp approach this paper addresses the self scheduling problem faced by a price maker to achieve maximum profit in a pool based electricity market an exact and computationally efficient mixed integer linear programming milp formulation of this problem is presented this formulation models precisely the price maker capability of altering market clearing prices to its own benefits through price quota curves no assumptions are made on the characteristics of the pool and its agents a realistic case study is presented and the results obtained are analyzed in detail

optimal bidding strategies for hydro electric producers a literature survey in a competitive environment with bid based markets power generation companies desire to develop bidding strategies that maximize their revenue in this paper we ask what approaches and methodologies have been used to model the bidding problem for hydro electric producers we present the problem s developments over time and through reviewing different variants of the problem progressively build to the case in which the agent is a price maker hydro electric producer in each variant of the bidding problem we examine how the approaches used to solve it may or may not be applicable to other variants last for the price maker hydro electric producer s bidding problem we recognize the most recent developments and illuminate a path for future efforts