price formation in electricity forward markets and the relevance of systematic forecast errors since the liberalisation of the european electricity sector forward and futures contracts have gained significant interest of market participants due to risk management reasons for pricing of these contracts an important fact concerns the non storability of electricity in this case according to economic theory forward prices are related to the expected spot prices which are built on fundamental market expectations in the following article the crucial impact parameters of forward electricity prices and the relationship between forward and future spot prices will be assessed by an empirical analysis of electricity prices at the european energy exchange and the nord pool power exchange in fact price formation in the considered markets is influenced by historic spot market prices yielding a biased forecasting power of long term contracts although market and risk assessment measures of market participants and supply and demand shocks can partly explain the futures spot bias inefficiencies in the analysed forward markets cannot be ruled out

electricity market integration decarbonisation and security of supply dynamic volatility connectedness in the irish and great britain markets abstract this study investigates the volatility connectedness between the irish and great britain electricity markets and how it is driven by changes in energy policy institutional structures and political ideologies we assess various aspects of this volatility connectedness including static unconditional vs dynamic conditional symmetric vs asymmetric characteristics between 2009 and 2018 we find that the volatility connectedness is time varying and it is significantly affected by important events policy reforms or market re designs such as brexit oil price slump an increasing share of renewables and fluctuations in the exchange rates our asymmetric analysis shows that magnitude of the good volatility connectedness is marginally larger than that of the bad volatility connectedness our result suggests that good volatility levels would be even higher once the irish market adopts the carbon price floor therefore supporting renewable generation by setting an appropriate price of carbon in interconnected wholesale electricity markets will improve market integration

the effect of asymmetries on optimal hedge ratios there is widespread evidence that the volatility of stock returns displays an asymmetric response to good and bad news this article considers the impact of asymmetry on time varying hedges for financial futures an asymmetric model that allows forecasts of cash and futures return volatility to respond differently to positive and negative return innovations gives superior in sample hedging performance however the simpler symmetric model is not inferior in a hold out sample a method for evaluating the models in a modern risk management framework is presented highlighting the importance of allowing optimal hedge ratios to be both time varying and asymmetric

the impact of renewable energy forecast errors on imbalance volumes and electricity spot prices abstract this paper contributes to the general consideration of whether a policy of incentivising system operators to improve the quality and market availability of forecasts for renewable energy outputs would be beneficial using data from the german electricity market we investigate the effect of wind and solar energy forecasts errors on imbalance volumes and subsequent spot electricity prices we use ordinary least squares regression quantile regression and autoregressive moving averages to identify these relationships using variables that have a quarter hourly data granularity the results show that higher wind and solar forecast errors increase the absolute values of imbalance volumes and that these can pass through into higher spot prices we find that wind forecast errors in germany impact spot prices more than solar forecasting errors policy incentives to improve the accuracy and availability of renewable energy forecasts by the system operators should therefore be encouraged

forecasting electricity prices and their volatilities using unobserved components abstract the liberalization of electricity markets more than ten years ago in the vast majority of developed countries has introduced the need of modelling and forecasting electricity prices and volatilities both in the short and long term thus there is a need of providing methodology that is able to deal with the most important features of electricity price series which are well known for presenting not only structure in conditional mean but also time varying conditional variances in this work we propose a new model which allows to extract conditionally heteroskedastic common factors from the vector of electricity prices these common factors are jointly estimated as well as their relationship with the original vector of series and the dynamics affecting both their conditional mean and variance the estimation of the model is carried out under the state space formulation the new model proposed is applied to extract seasonal common dynamic factors as well as common volatility factors for electricity prices and the estimation results are used to forecast electricity prices and their volatilities in the spanish zone of the iberian market several simplified alternative models are also considered as benchmarks to illustrate that the proposed approach is superior to all of them in terms of explanatory and predictive power

robust estimation and forecasting of the long term seasonal component of electricity spot prices when building stochastic models for electricity spot prices the problem of uttermost importance is the estimation and consequent forecasting of a component to deal with trends and seasonality in the data while the short term seasonal components daily weekly are more regular and less important for valuation of typical power derivatives the l ong term seasonal components ltsc seasonal annual are much more diffi cult to tackle surprisingly in many academic papers dealing with electricity spot price modeling the importance of the seasonal decomposition is neglected and the problem of forecasting it is not considered with this paper we want to fill the gap and present a thorough study on estimation and forecasting of the ltsc of electricity spot prices we consider a battery of models based on fourier or wavelet decomposition combined with linear or exponential decay we find that all considered wavelet base d models are significantly better in terms of forecasting spot prices up to a year ahead than all considered sine based models this result questions the validity and usefulness of stochastic models of spot electricity prices built on sinusoidal long term seasonal components

greener more integrated and less volatile a quantile regression analysis of italian wholesale electricity prices abstract this paper provides estimates of quantile regression models of the relationship between italian day ahead electricity prices the supply of renewables and the inception of a new cable sapei linking sardinia with the italian peninsula in the 2006 2015 time window the results confirm the merit order effects detected in the existing literature both for photovoltaics and wind power more strongly in market conditions characterised by moderately low price levels and with some implied increase in volatility the new cable has apparently challenged the ability of power generating companies to extract value through price spikes has mitigated volatility and its effects have been complementary with those of renewables effects from photovoltaics are more sensitive to robustness checks differences across zonal markets are nonetheless detected

electricity prices large scale renewable integration and policy implications abstract this paper investigates the effects of intermittent solar and wind power generation on electricity price formation in germany we use daily data from 2010 to 2015 a period with profound modifications in the german electricity market the most notable being the rapid integration of photovoltaic and wind power sources as well as the phasing out of nuclear energy in the context of a garch in mean model we show that both solar and wind power granger cause electricity prices that solar power generation reduces the volatility of electricity prices by scaling down the use of peak load power plants and that wind power generation increases the volatility of electricity prices by challenging electricity market flexibility

factor models in the german electricity market stylized facts seasonality and calibration abstract the class of arithmetic factor models is flexible enough to model all stylized facts occurring in electricity markets including negative prices while still yielding tractable derivative prices in this paper we conduct a thorough review of the requirements and possibilities of factor models we compare different seasonality functions and study their power to deseasonalise day ahead spot prices from the epex germany austria market furthermore we introduce an alternative method to estimate mean reversion speed based on arma time series and a method to evaluate the distributional fit of the model to realised market prices which we apply to two non gaussian estimated models

cointegration analysis of spot electricity prices insights on transmission efficiency in the western us abstract the us energy policy act of 1992 promoted the development of spot markets for electric power by requiring utilities to open their transmission systems to wholesale power sales in this paper we specify and estimate a vector error correction model using peak and off peak electricity spot prices during 1994 1996 covering 11 regional markets in the western united states and test these prices for evidence of market integration the results show evidence of an efficient and stable wholesale power market

dilemmas of export diversification in a developing economy mexican oil in the 1980s abstract small states usually find it very costly to implement strategies with the objective of reducing their dependence on great economic powers this essay seeks to explain the accomplishments and failures of mexico s efforts to diversify its foreign economic relations beyond the united states though mexican exports to the industrialized world have surged in the 1980s their excessive concentration on oil has skewed mexico s trade profile and stunted the growth of non oil industries moreover while exports of non oil products have expanded fourfold over the last decade they remain concentrated as well within the us market if protectionism in the latter continues to grow the slow but steady new orientation of mexican business toward foreign markets will prove more effective than the government s political security considerations of recent years in leading them to diversify mexico s profile of foreign economic relations beyond the united states

realized volatility and the influence of market measures on predictability analysis of nord pool forward electricity data abstract this is the first paper to utilize intra daily high frequency data and to apply known market measures for the prediction of volatility in the nord pool electricity forward market the work is based on recent methods of separating realized volatility into two components continuous and jump volatilities in addition the link between future price volatility and current observable economic variables is examined the measures trading volume time to maturity asymmetric effect from negative shocks and intra week seasonality are assessed to identify improvements in day ahead predictions the model where the total variation is separated into its continuous and jump components is compared with the simpler heterogeneous autoregressive model of realized variation both in and out of sample the results show a strong degree of persistence in realized volatility and significant impacts from the mentioned market measures when predicting nord pool forward price volatility hence there is a clear preference for models accounting for the systematic impact of market measures to improve volatility assessment for tomorrow moreover separating the total variation into continuous and jump components seems potentially useful when predicting day ahead volatility

predicting price spikes in electricity markets using a regime switching model with time varying parameters this paper shows that a stochastic regime switching model can represent the volatile behavior of wholesale electricity prices associated with price spikes effectively the structure of the model is very flexible because the mean prices in the two regimes and the two transition probabilities are functions of the load and or the implicit reserve margin using price data from the single settlement market in pjm may 1999 to may 2000 the results show that the estimated switching probability from the low to the high regime predicts price spikes well if the reserve margin is measured accurately

evaluating the market splitting determinants evidence from the iberian spot electricity prices abstract this paper aims to assess the main determinants on the market splitting behaviour of the iberian electricity spot markets iberia stands as an ideal case study where the high level deployment of wind power is observed together with the implementation of the market splitting arrangement between the portuguese and the spanish spot electricity markets logit and non parametric models are used to express the probability response for market splitting of day ahead spot electricity prices as a function of the explanatory variables representing the main technologies in the generation mix wind hydro thermal and nuclear power together with the available transfer capacity and electricity demand logit models give preliminary indications about market splitting behaviour and then notwithstanding the demanding computational challenge a non parametric model is applied in order to overcome the limitations of the former models results show an increase of market splitting probability with higher wind power generation or more generally with higher availability of low marginal cost electricity such as nuclear power generation the european interconnection capacity target of 10 of the peak demand of the smallest interconnected market might be insufficient to maintain electricity market integration therefore pro active coordination policies governing both interconnections and renewables deployment should be further developed

dependence structure in the australian electricity markets new evidence from regular vine copulae abstract in this study regular vine copula was used to investigate the dependence structure of electricity prices at the state level in the australian national electricity market nem during three periods related to the adoption and abolition of the carbon tax in the pre carbon period we found evidence of tail dependence separately in the northern and southern nem but not across them during the carbon period the joint spike in the northern nem disappeared and the tail dependence in the southern nem decreased in the post carbon period the best dependence structure turned out to be a flexible structure of the regular vine which exactly matches the geographical infrastructure connectedness of transmission wires besides both upper and lower tail dependences were found in all adjacent states after the abolition of the carbon tax suggesting a more integrated market regarding tail dependence our findings have substantial implications for risk management in the nem especially for those participants exposed to multiple states

renewables diffusion and contagion effect in italian regional electricity markets assessment and policy implications abstract in the electricity market sudden price jumps occur more frequently than in other markets due to the peculiarity of electricity furthermore the structural spot characteristics of the electricity market determine high price variability all these characteristics have been accentuated by the dramatic increase of renewable energy supply in italy starting in 2010 these features suggest the possibility of contagion effects across italian regional electricity markets considering contagion such as a sudden and significant increase in cross market links arising from a shock to a specific market in this paper we investigate whether such a renewable energy increase has affected the contagion behavior in the italian electricity spot market taking into account both the difference between interdependence and contagion and the direction of the shock we find empirical evidence with significant tests that no changes have occurred in interdependence mechanism nor in contagion effects due to renewable energy sources development in italy

a multivariate garch model of international transmissions of stock returns and volatility the case of the united states and canada this study examines the short run dynamics of returns and volatility for stocks traded on the new york and toronto stock exchanges the main finding is that inferences about the magnitude and persistence of return innovations that originate in either market and that transmit to the other market depend importantly on how the cross market dynamics in volatility are modeled moreover much weaker cross market dynamics in returns and volatility prevail during later subperiods and especially for canadian stocks with shares dually listed in new york implications for international asset pricing hedging strategies and regulatory policy are discussed

the effect of a new power cable on energy prices volatility spillovers abstract in this paper we estimate volatility spillovers before and after the introduction of a new cable linking different electricity market zones using wholesale electricity prices for sardinia and two neighbouring italian market zones for the period 2005 2015 we focus on the effects of the sapei cable fully operational since march 2011 var garch estimates indicate that the sapei cable allowed for stronger volatility transmission towards sardinia a smaller zone and a net importer from its new neighbour the central southern zone albeit the effect was significant only off peak higher conditional correlations between zonal prices are also observed after the cable was introduced some implications are drawn about the interaction between market size export positions congestion and volatility transmission

cvar models with selective hedging for international asset allocation abstract we develop an integrated simulation and optimization framework for multicurrency asset allocation problems the simulation applies principal component analysis to generate scenarios depicting the discrete joint distributions of uncertain asset returns and exchange rates we then develop and implement models that optimize the conditional value at risk cvar metric the scenario based optimization models encompass alternative hedging strategies including selective hedging that incorporates currency hedging decisions within the portfolio selection problem thus the selective hedging model determines jointly the portfolio composition and the level of currency hedging for each market via forward exchanges we examine empirically the benefits of international diversification and the impact of hedging policies on risk return profiles of portfolios we assess the effectiveness of the scenario generation procedure and the stability of the model s results by means of out of sample simulations we also compare the performance of the cvar model against that of a model that employs the mean absolute deviation mad risk measure we investigate empirically the ex post performance of the models on international portfolios of stock and bond indices using historical market data selective hedging proves to be the superior hedging strategy that improves the risk return profile of portfolios regardless of the risk measurement metric although in static tests the mad and cvar models often select portfolios that trace practically indistinguishable ex ante risk return efficient frontiers in successive applications over several consecutive time periods the cvar model attains superior ex post results in terms of both higher returns and lower volatility

integration of regional electricity markets in australia a price convergence assessment abstract from an electricity market design perspective it is relevant and practical to know which market structures allow for price convergence and how long this takes to achieve this study employs the phillips and sul 2007 2009 methodology to test for the convergence of wholesale electricity prices across the australian states we identify a long run common price growth pattern that applies to a cluster formed by three eastern states that share common market characteristics and limited physical interconnection we also find another cluster with less competitive market structures that although not interconnected strongly converge towards their own trend these findings confirm theoretical expectations while quantifying the rate of convergence finally we also investigate the role that the carbon tax regime has played in the convergence process with new empirical showing that the previous results are not affected with the notable exception being the case of south australia

impact of optimal storage allocation on price volatility in energy only electricity markets recent studies show that the fast growing expansion of wind power generation may lead to extremely high levels of price volatility in wholesale electricity markets storage technologies regardless of their specific forms e g pump storage hydro large scale or distributed batteries are capable of alleviating the extreme price volatility levels due to their energy usage time shifting fast ramping and price arbitrage capabilities in this paper we propose a stochastic bilevel optimization model to find the optimal nodal storage capacities required to achieve a certain price volatility level in a highly volatile energy only electricity market the decision on storage capacities is made in the upper level problem and the operation of strategic regulated generation storage and transmission players is modeled in the lower level problem using an extended stochastic bayesian cournot based game the south australia sa electricity market which has recently experienced high levels of price volatility and a 30 bus ieee system are considered as the case studies our numerical results indicate that 50 price volatility reduction in the sa electricity market can be achieved by installing either 430 mwh regulated storage or 530 mwh strategic storage in other words regulated storage firms are more efficient in reducing the price volatility than strategic storage firms

asymmetric volatility in european day ahead power markets a comparative microeconomic analysis this paper uses high frequency spot price data from fourteen wholesale electricity markets in europe to analyze asymmetric volatility in european day ahead power markets with exponential garch e garch and tarch models our data set ranges from 1992 to 2015 and consists of approximately 926 000 observations as such this paper constitutes the most extensive and comprehensive work conducted so far on european power markets to the best of our knowledge unlike most of the literature that treats price as a continuous variable and attempts to model its trajectory this paper adopts a unique approach and regards each hour in a day a separate market the results show in post 2008 period the most expensive electricity is consumed in turkey ireland and uk while the cheapest power is in russia nordic countries and czech republic russia poland and czech republic have the least volatile markets while france ireland and portugal have the most volatile ones volatility has decreased in many european countries in post 2008 period besides we find magnitude effect is usually larger than the leverage effect meaning that the absolute value of price change is relatively more important than the sign of the change whether it is an increase or a decrease to explain volatility in european day ahead power markets moreover the results imply there is not a uniform inverse leverage effect in electricity prices that is price increases are more destabilizing in some european markets e g poland slovenia ireland netherlands than comparable price decreases but vice versa also holds true in some other countries e g portugal and france leverage or inverse leverage effect in post 2008 period is relatively stronger in portugal france and ireland but its impact is quite limited in turkey and germany furthermore although the impact of seasonality on prices is obvious a specific pattern cannot be identified finally large changes in the volatility will affect future volatilities for a relatively longer period of time in nordic countries ireland and the uk while changes in current volatility will have less effect on future volatilities in czech republic russia and turkey

stochastic price modeling of high volatility mean reverting spike prone commodities the australian wholesale spot electricity market it is commonly known that wholesale spot electricity markets exhibit high price volatility strong mean reversion and frequent extreme price spikes this paper employs a basic stochastic model a mean reverting model and a regime switching model to capture these features in the australian national electricity market nem comprising the interconnected markets of new south wales queensland south australia and victoria daily spot prices from 1 january 1999 to 31 december 2004 are employed the results show that the regime switching model outperforms the basic stochastic and mean reverting models electricity prices are also found to exhibit stronger mean reversion after a price spike than in the normal period and price volatility is more than fourteen times higher in spike periods than in normal periods the probability of a spike on any given day ranges between 5 16 in nsw and 9 44 in victoria

forecasting the joint distribution of australian electricity prices using dynamic vine copulae abstract we consider the problem of modelling and forecasting the distribution of a vector of prices from interconnected electricity markets using a flexible class of drawable vine copula models where we allow the dependence parameters of the constituting bivariate copulae to be time varying we undertake in sample and out of sample tests using daily electricity prices and evidence that our model provides accurate forecasts of the underlying distribution and outperforms a set of competing models in their abilities to forecast one day ahead conditional quantiles of a portfolio of electricity prices our study is conducted in the australian national electricity market nem which is the most efficient power auction in the world electricity prices exhibit highly stylised features such as extreme price spikes price dependency between regional markets correlation asymmetry and non linear dependency the developed approach can be used as a risk management tool in the electricity retail industry which plays an integral role in the apparatus of modern energy markets electricity retailers are responsible for the efficient distribution of electricity while being exposed to market risk with extreme magnitudes

a note on using the hodrick prescott filter in electricity markets abstract recently nowotarski et al 2013 have found that wavelet based models for the long term seasonal component ltsc are not only better in extracting the ltsc from a series of spot electricity prices but also significantly more accurate in terms of forecasting these prices up to a year ahead than the commonly used monthly dummies and sine based models however a clear disadvantage of the wavelet based approach is the increased complexity of the technique as compared to the other two classes of ltsc models and the resulting need for dedicated numerical software which may not be readily available to practitioners in their work environments to facilitate this problem we propose here a much simpler yet equally powerful method for identifying the ltsc in electricity spot price series it makes use of the hodrick prescott hp filter a widely recognized tool in macroeconomics

forecasting spot price volatility using the short term forward curve abstract we use high frequency real time spot prices and day ahead forward prices from the pennsylvania new jersey maryland wholesale electricity market to calculate describe and forecast spot price volatility we introduce the concept of forward realized volatility calculated from day ahead forward prices forward realized volatility improves forecasts of spot price volatility in the sense of higher r 2 s and significantly lower forecast errors when compared with forecasts based solely upon historical volatility the largest forecast improvements obtained when the change in forward realized volatility is large in magnitude splitting total volatility into its continuous and jump components is crucial for forecasting volatility at weekly and monthly horizons

modelling interregional links in electricity price spikes abnormally high price spikes in spot electricity markets represent a significant risk to market participants as such a literature has developed that focuses on forecasting the probability of such spike events moving beyond simply forecasting the level of price many univariate time series models have been proposed to dealwith spikes within an individual market region this paper is the first to develop a multivariate self exciting point process model for dealing with price spikes across connected regions in the australian national electricity market the importance of the physical infrastructure connecting the regions on the transmission of spikes is examined it is found that spikes are transmitted between the regions and the size of spikes is influenced by the available transmission capacity it is also found that improved risk estimates are obtained when inter regional linkages are taken into account

asset allocation in a downside risk framework 1991 asset allocation in a downside risk framework financial analysts journal vol 47 no 5 pp 28 40

switching outputs in a bioenergy cogeneration project a real options approach abstract environmental concerns have stimulated the search for economically feasible renewable energy projects one such alternative is the use of biomass for energy generation which has increasingly been the focus of interest traditional valuation methods on the other hand fail to capture the value of the embedded options that exist in many of these projects which may lead to non optimal investment decisions in this article we analyze the feasibility of installing a cogeneration unit in an industrial plant in brazil in order to extract value from biomass residue currently discarded which can be used for thermal and electric energy generation the cogeneration unit also allows the firm the flexibility to optimally choose between an increase in production or the generation of surplus energy for sale in the short term market once additional investment in interconnection to the grid is made we model the uncertainty over future energy prices as a mean reverting process with jumps and seasonality and the embedded flexibility as a bundle of european options under the real options approach the results indicate that the investment in the cogeneration plant is warranted and that the option to switch outputs adds significant value to the project which suggests that biomass residue may be a sustainable energy alternative in this case

an assessment of the united nations scale of assessments from a developing country standpoint abstract the united nations apportionment of its expenses among its member countries is examined in a public choice context the special nature of un produced public goods the un voting rules and its zero sum method of allocating expenses all act to reduce the size of un output and to exacerbate country group conflict the developing country groups throw a disproportionate burden of un financing on the developed countries this result is captured by a model of un burden sharing both more rational and simpler than the un practice jel f33 h41

modelling price and volatility inter relationships in the australian wholesale spot electricity markets this paper examines the inter relationships of wholesale spot electricity prices among the four regional electricity markets in the australian national electricity market nem namely new south wales queensland south australia and victoria using the constant conditional correlation and tse and tsui s tse y k tsui a k c 2002 a multivariate generalised autoregressive conditional heteroscedasticity model with time varying correlations journal of business and economic statistics 20 3 351 362 and engle s engle r 2002 dynamic conditional correlation a sample class of multivariate generalized autoregressive conditional heteroskedasticity models journal of business and economic statistics 20 3 339 350 dynamic conditional correlation multivariate garch models tse and tsui s tse y k tsui a k c 2002 a multivariate generalised autoregressive conditional heteroscedasticity model with time varying correlations journal of business and economic statistics 20 3 351 362 dynamic conditional correlation multivariate garch model which takes account of the student t specification produces the best results at the univariate garch 1 1 level the mean equations indicate the presence of positive own mean spillovers in all four markets and little evidence of mean spillovers from the other lagged markets in the dynamic conditional correlation equation the highest conditional correlations are evident between the well connected markets indicating the presence of strong interdependence between these markets with weaker interdependence between the not so well interconnected markets

electricity pool prices a case study in nonlinear time series modelling this paper considers modelling the behaviour of prices in the english and welsh wholesale electricity pool since the creation of this spot market in 1990 the process turns out to be nonlinear and a logistic smooth transition autoregressive model is fitted and shown to be superior to a linear alternative the behaviour of the estimated model is discussed and it is seen that nonlinearity is needed to describe the institutional characteristics and historical path of pool prices

arch models properties estimation and testing abstract the aim of this survey paper is to provide an account of some of the important developments in the autoregressive conditional heteroskedasticity arch model since its inception in a seminal paper by engle 1982 this model takes account of many observed properties of asset prices and therefore various interpretations can be attributed to it we start with the basic arch models and discuss their different interpretations arch models have been generalized in different directions to accommodate more and more features of the real world we provide a comprehensive treatment of many of the extensions of the original arch model next we discuss estimation and testing for arch models and note that these models lead to some interesting and unique problems there have been numerous applications and we mention some of these as we present different models the paper includes a glossary of the acronyms for the models we describe

hics mics nics and lics some elements in the political economy of graduation and differentiation abstract the demand by industrialized high income countries hics that the newly industrialized countries nics should graduate out of the so called third world by surrendering preferential treatment in hic markets and by gradually conforming to the rules of gatt is proving to be a contentious issue in north south relations today having examined the concept and components of graduation and the origins of differential and preferential treatment for ldcs in world markets the paper presents arguments for and against graduation distinguishing between its implications not only for hics and nics but also for other middle income and low income countries mics and lics finally the paper discusses criteria which might be used in the application of graduation and the countries and products to which itmight be applied

integrated portfolio management with options in this paper we examine the problem of managing portfolios consisting of both stocks and options for the simultaneous optimization of stock and option positions we base our analysis on the generally accepted mean variance framework first we analyze the effects of options on the mean variance efficient frontier if they are considered as separate investment alternatives due to the resulting asymmetric portfolio return distribution mean variance analysis will be not sufficient to identify optimal optioned portfolios additional investor preferences which are expressed in terms of shortfall constraints allow a more detailed portfolio specification under a mean variance and shortfall preference structure we then derive optioned portfolios with a maximum expected return to circumvent the technical optimization problems arising from stochastic constraints we use an approximation of the return distribution and develop economically meaningful conditions under which the complex optimization problem can be transformed into a linear problem being comparably easy to solve empirical results based on both empirical market data and monte carlo simulations illustrate the portfolio optimization procedure with options

realized volatility and price spikes in electricity markets the importance of observation frequency abstract this paper uses high frequency spot price data from eight wholesale electricity markets in australia canada and the united states to estimate realized volatility and the frequency of price spikes i find similar levels of realized volatility in australia and north america with estimates ranging from 1500 to 2700 much greater than estimates reported previously in the literature in hourly data the frequency of price spikes ranges from approximately 35 to 40 in seven of eight markets i present evidence that increasing the lag length in the calculation of bipower variation improves jump detection in electricity prices

correlations and volatility spillovers between oil prices and the stock prices of clean energy and technology companies abstract in this paper multivariate garch models are used to model conditional correlations and to analyze the volatility spillovers between oil prices and the stock prices of clean energy companies and technology companies four different multivariate garch models bekk diagonal constant conditional correlation and dynamic conditional correlation are compared and contrasted the dynamic conditional correlation model is found to fit the data the best and generates results showing that the stock prices of clean energy companies correlate more highly with technology stock prices than with oil prices on average a 1 long position in clean energy companies can be hedged for 20 cents with a short position in the crude oil futures market

transmission of prices and price volatility in australian electricity spot markets a multivariate garch analysis this paper examines the transmission of spot electricity prices and price volatility among the five regional electricity markets in the australian national electricity market namely new south wales queensland south australia the snowy mountains hydroelectric scheme and victoria a multivariate generalised autoregressive conditional heteroskedasticity model is used to identify the source and magnitude of price and price volatility spillovers the results indicate the presence of positive own mean spillovers in only a small number of markets and no mean spillovers between any of the markets this appears to be directly related to the physical transfer limitations of the present system of regional interconnection nevertheless the large number of significant own volatility and cross volatility spillovers in all five markets indicates the presence of strong autoregressive conditional heteroskedasticity and generalised autoregressive conditional heteroskedasticity effects this indicates that shocks in some markets will affect price volatility in others finally and contrary to evidence from studies in north american electricity markets the results also indicate that australian electricity spot prices are stationary

the impact of australian ets news on wholesale spot electricity prices an exploratory analysis this article investigates the impact of news concerning the development of emissions trading in australia such as the carbon pollution reduction scheme cprs on wholesale electricity spot prices by using a database of 117 news announcements from december 1 1998 to july 1 2009 as power producers constitute the bulk of the participants of the proposed australian emissions trading scheme regulatory changes about allocation banking coverage targets are indeed likely to affect the five interconnected electricity markets in new south wales queensland south australia victoria and tasmania we assess these effects with an arma 1 1 garch 1 1 model where daily electricity spot prices are regressed against exogenous variables in the mean and variance equations this article constitutes the first empirical analysis of australian ets news effects on electricity wholesale spot prices our results show two asymmetric types of news effects depending on their information content

counterfactual comparisons of investment options for wind power and agricultural production in the united states lessons from northern ohio abstract we analyze potential efficiency gains in wind power projects by comparing counterfactual investment decisions in two different scenarios under a real options framework the first scenario is a standard wind power investment where the investor rents the land from local farms in the second scenario the wind power investor buys the land and commercializes both electricity and crop production thus reducing the revenue risk through the diversification both scenarios have a waiting option with the wholesale prices leading the installation decision we model the electricity price as a mean reverting process with jumps and with different jumping probabilities for the different seasons of the year corn prices follow a mean reverting process the waiting flexibility was modeled as a bundle of european options the results indicate that the waiting option is exercised in 100 of our simulations in both scenarios suggesting the still important role of government policies to stimulate wind power more importantly in more than 90 of the simulations the second scenario brought value to the investment furthermore net present values are more sensitive to reductions in capital costs than electricity prices these results can form the basis for more effective policies for the wind power sector

the hedging performance of electricity futures on the nordic power exchange the nordic power exchange nord pool the first multinational exchange for electricity trading has existed since january 1996 spot and futures contracts are traded on this exchange and its typical characteristics are very high volatilities as well as non normally distributed returns this article looks at electricity futures and how they can be used for short term hedging of positions taken in the spot market it studies the minimum variance hedge ratio and how it can be estimated in different ways the traditional naive hedge and the ols hedge are compared out of sample to more elaborate moving average and garch hedges and the empirical results indicate some gains from hedging with futures despite the lack of straight forward arbitrage possibilities in the electricity market furthermore we find a slightly better performance of the simple ols hedge compared to the conditional hedges

regime jumps in electricity prices many countries are liberalizing their energy markets participants in these markets are exposed to market risk due to the characteristics of electricity price dynamics electricity prices are known to be mean reverting very volatile and subject to frequent spikes models that describe the dynamics of electricity prices should incorporate these characteristics in order to capture the price spikes many researchers have introduced stochastic jump processes but we argue and show that this specification might lead to potential problems with specifying the true amount of mean reversion within the process in this paper we propose a regime switching model that models price spikes separated from normal mean reverting prices

good volatility bad volatility what drives the asymmetric connectedness of australian electricity markets efficient delivery of network services and the electricity infrastructure to meet the long term consumer s interests are the main objectives and the strategies of a national electricity market while the main interests of generators are to maximize their profit through pricing strategies therefore the objective of this study is to explore whether electricity prices across the four australian states display symmetric price volatility connectedness the study is the first attempt in the literature to make use of intraday 5 min australian dispatch electricity prices spanning the period december 8th 1998 to may 5th 2016 to quantify asymmetries in volatility connectedness emerging from good and bad volatility the results provide supportive evidence that the australian electricity markets are connected asymmetrically implying the presence of some degree of market power that is exercised by generators across regional electricity markets

germany s nuclear power plant closures and the integration of electricity markets in europe this paper examines the potential implications of national policies that lead to a sudden increase of wind power in the electricity mix for interconnected european electricity markets more specifically it examines market integration before and after the closures of eight nuclear power plants that occurred within a period of a few months in germany during 2011 the short and long run interrelationships of daily electricity spot prices from november 2009 to october 2012 in apx endex belpex epex de epex fr nordpool omel and swissix and wind power in the german system are analysed two mgarch multivariate generalized autoregressive conditional heteroscedasticity models with dynamic correlations are used to assess spot market behaviour in the short run and a fractional cointegration analysis is conducted to investigate changes in the long run behaviour of electricity spot prices results show positive time varying correlations between spot prices in markets with substantial shared interconnector capacity a negative association between wind power penetration in germany and electricity spot prices in the german and neighbouring markets and for most markets a decreasing speed in mean reversion

are daily and weekly load and spot price dynamics in australia s national electricity market governed by episodic nonlinearity in this article we use half hourly spot electricity prices and load data for the national electricity market nem of australia for the period from december 1998 to june 2009 to test for episodic nonlinearity in the dynamics governing daily and weekly cycles in load and spot price time series data we apply the portmanteau correlation bicorrelation and tricorrelation tests introduced in hinich 1996 to the time series of half hourly spot prices and load demand from 7 12 1998 to 30 06 2009 using a fortran 95 program we find the presence of significant third and fourth order nonlinear serial dependence in the weekly load and spot price data in particular but to a much more marginal extent in the daily data

renewable energy regulation and structural breaks an empirical analysis of spanish electricity price volatility abstract international experience proves that electricity prices have undergone major changes in volatility since the entry of green technologies the intermittency of renewable sources is one of the reasons for these changes as it leads to higher volatility in periods of higher participation by renewables we argue that the development of the regulatory system promoting renewable electricity also plays a crucial role we raise a question that deserves attention could an incentive scheme induce higher share of renewables and lower volatility simultaneously in this paper we conduct an empirical analysis with spanish data we analyze possible ensuing structural changes in spanish electricity spot price volatility from january 2002 to december 2017 we identify two structural breaks linked to important measures related to renewable electricity i the abolishment of the feed in tariff scheme and ii the establishment of a more market oriented regulation based on investment and operating costs we conclude that stable regulatory policies reduce volatility even though the presence of renewable sources is greater furthermore market based policy measures achieve lower volatility encouraging good integration of intermittent renewable electricity

a dynamic network analysis of spot electricity prices in the australian national electricity market abstract this study applies dynamic network analysis to the power sector examining the relationship between regional spot electricity prices in the australian national electricity market nem in particular we employ principal component analysis and generate granger causality networks to examine the degree of interconnectedness of the nem in a time varying setting we find that the derived measures of interdependence can be related to actual market events such as price spikes unexpected high demand for electricity sudden increases in price volatility rebidding of dominant generators the temporary or permanent outage of major power stations and upgrades and limitations in transmission capacity in the analysed network we find that stronger dependence is exhibited by regional markets that are linked through interconnectors while the direction of granger causality can be related to interregional trade we further examine the usefulness of the derived measures for forecasting distributional characteristics of spot prices such as the maximum price volatility price spreads or upcoming periods of price spikes our results suggest that the derived network measures have predictive power albeit limited for the behaviour of spot electricity prices in the nem