Price formation and market power in the German wholesale electricity market in 2006

From 2002 to 2006, German wholesale electricity prices more than doubled. The purpose of this paper is to estimate the price components in 2006 in order to identify the factors responsible for the increase. We develop a competitive benchmark model, taking into account power plant characteristics, fuel and CO₂-allowance prices, wind generation, cross-border flows, unit commitment, and startup conditions, to estimate the difference between generation costs and observed market prices for every hour in 2006. We find that prices at the German wholesale market (European Energy Exchange—EEX) are above competitive levels for a large fraction of the observations. We verify the robustness of the results by carrying out sensitivity analyses. We also address the issue of revenue adequacy.     

Dynamic analysis of the German day-ahead electricity spot market

This paper analyzes the dynamic behavior of day-ahead spot prices in the German electricity spot market due to positive structural shocks in wind and solar power. It uses a dynamic structural vector autoregressive model to estimate the related structural impulse response functions. The estimates suggest that wind power shocks have a more prolonged negative effect on spot prices than solar power shocks. Significant autocorrelations of wind power for larger lags indicate these results. The total negative merit order effect of a solar power shock is larger when using a reasonable model specification. One reason might be that solar power shocks coincide with demand peaks. However, results regarding the relation of the effects of wind and solar should be dealt with carefully because these results do not hold for all specifications. Past static estimates show differences in the total average negative merit order effects. These estimates might be overstated if wind and solar power dynamics are transferred to the merit order effects.     

Abuse of dominance and antitrust enforcement in the German electricity market

In 2008, the European Commission investigated E.ON, a large and vertically integrated electricity company, for the alleged abuse of a joint dominant position by strategically withholding generation capacity in the German wholesale electricity market. The case was settled after E.ON agreed to divest 5 GW generation capacity as well as its extra-high voltage network. We analyze the effect of these divestitures on wholesale electricity prices. Our identification strategy is based on the observation that energy suppliers have more market power during peak periods when demand is high. Therefore, a decrease in market power should lead to convergence between peak and off-peak prices, after controlling for different demand and supply conditions as well as the change in generation mix due to the expansion of renewable technologies. Using daily electricity prices for the 2006–2012 period, we find economically and statistically significant convergence effects after the settlement of the case. In a richer specification, we show that the price reductions appear to be mostly due to the divestiture of gas and coal plants, which is consistent with merit-order considerations. Additional cross-country analyses support our results.     

Simulation of current pricing-tendencies in the German electricity market for private consumption

The German electricity market for private consumption is characterized by increasing prices and low participation of the consumers. This prompts us to investigate the interdependencies between the customers’ engagement in the market and the suppliers’ pricing strategies. Based on an analysis of the German retail market, an agent-based simulation model is developed. Whereas the behaviour of private customers is calibrated on field data, the suppliers learn to maximize profits with a feedback-learning heuristic. The simulation results show a tendency of rising prices, which are created without the assumption of tacit collusion among suppliers. We conclude that in Germany the current market pressure of private customers may not be a sufficient incentive for suppliers to lower electricity prices.     

An agent-based analysis of the German electricity market with transmission capacity constraints

While some agent-based models have been developed for analyzing the German electricity market, there has been little research done on the emerging issue of intra-German congestion and its effects on the bidding behavior of generator agents. Yet, studies of other markets have shown that transmission grid constraints considerably affect strategic behavior in electricity markets. In this paper, the implications of transmission constraints on power markets are analyzed for the case of Germany. Market splitting is applied in the case of congestion in the grid. For this purpose, the agent-based modeling of electricity systems (AMES) market package developed by Sun and Tesfatsion is modified to fit the German context, including a detailed representation of the German high-voltage grid and its interconnections. Implications of transmission constraints on prices and social welfare are analyzed for scenarios that include strategic behavior of market participants and high wind power generation. It can be shown that strategic behavior and transmission constraints are inter-related and may pose severe problems in the future German electricity market.     

Competition effects of mergers: An event study of the German electricity market

This paper investigates the competition effects of the entry of Vattenfall into the German electricity market. While the competition authorities supported the entry by approving Vattenfall’s acquisition of three regional utilities, other market participants raised concerns over the emergence of an upcoming oligopoly in the German market for power generation. We contrast the efficiency hypothesis postulating pro-competitive effects of mergers with the market power hypothesis postulating anti-competitive effects. For the analysis of the two opposing hypotheses, we use an event study approach to the stock prices of Vattenfall’s competitors in the German market. While we find no empirical evidence for increased market power in the German electricity market due to Vattenfall’s mergers, there is some indication for efficiency increases. We therefore cannot oppose the view of the competition authorities predicting an overall positive effect for consumers as a result of Vattenfall’s entry into the German electricity market.     

Econometric analysis of 15-minute intraday electricity prices

The trading activity in the German intraday electricity market has increased significantly over the last years. This is partially due to an increasing share of renewable energy, wind and photovoltaic, which requires power generators to balance out the forecasting errors in their production. We investigate the bidding behaviour in the intraday market by looking at both last prices and continuous bidding, in the context of a reduced-form econometric analysis. A unique data set of 15-minute intraday prices and intraday-updated forecasts of wind and photovoltaic has been employed. Price bids are explained by prior information on renewables forecasts and demand/supply market-specific exogenous variables. We show that intraday prices adjust asymmetrically to both forecasting errors in renewables and to the volume of trades dependent on the threshold variable demand quote, which reflects the expected demand covered by the planned traditional capacity in the day-ahead market. The location of the threshold can be used by market participants to adjust their bids accordingly, given the latest updates in the wind and photovoltaic forecasting errors and the forecasts of the control area balances.     

Trading behaviour on the continuous intraday market Elbas

Intraday markets for electricity allow for trading of energy until shortly before the period of delivery. This offers market participants a possibility to reduce their expected imbalances and to offer own unused flexibility. Because this form of distributed balancing before the period of delivery can be profitable for market participants as well as beneficial for system operations, intraday trading is expected to gain more importance in future, especially with increasing shares of variable renewable energy sources in the generation mix.So far, intraday markets are still a research field with many open questions. This paper contributes by a first analysis of intraday trades on Elbas, one of the European intraday markets. The analysis gives a detailed picture on trading activity and price development and is intended to improve understanding of continuous intraday trading.Findings include that trading activity differs significantly between price zones, that most trades occur in the last hours before gate closure and that market participants have to handle substantial price variations during the trading period. The paper also investigates the imbalance settlement rules in the Nordic countries and studies which effects one- and two-price imbalance settlement systems have on the market participants' profitability of intraday trading.     

Risk premia in the German day-ahead electricity market revisited: The impact of negative prices

This paper replicates the study by Viehmann (2011) that investigated risk premia in the German day-ahead electricity market from October 2005 to September 2008. While estimated sizes of risk premia can be replicated, this paper does not reproduce respective standard errors, leading to remarkable differences between the reported significance levels. An extension with data of preceding years points to further differences with respect to size and statistical significance. In addition, this paper analyzes the impact of negative prices on risk premia. Negative electricity prices were introduced in 2008 at the European Power Exchange (EPEX), and in 2013 at the Energy Exchange Austria (EXAA). The results of an econometric analysis suggest that the introduction of negative prices has led to a decrease in risk premia when compared to the period of a positive price regime.     

Factor models in the German electricity market: Stylized facts,seasonality, and calibration

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.     

Solar feed-in tariffs and the merit order effect: A study of the German electricity market

This study investigates the merit order effect (MOE) of the recent years' implementation of solar power in Germany. Market clearing electricity prices and production levels are compared for the years 2009–2011, and a model for the relationship between the electricity price and price sensitive electricity production is developed and applied to predict electricity prices in Germany from July 2010 to July 2011 with and without solar electricity generation (SEG). The results show that the SEG has caused a 7% reduction in average electricity prices for this period. The average daily maximum price and daily price variation are also found to decrease, by 13% and 23%, respectively. When taking the MOE into account the net consumer's cost of the solar feed-in tariff (FIT) system is found to be 23% less than the charge listed in the electricity bill. The German FIT policy for solar power has been subject to considerable public debate, and a common argument brought up in disfavor of the system is the high cost for the consumers. In this study we demonstrate the importance of including the MOE when evaluating the total costs and benefits of the FIT policy mechanism.     

Convergence bids and market manipulation in the California electricity market

Financial instruments are designed to improve the efficiency of a physical market in theory. In practice, underlying physical relationships may prevent financial instruments from working as intended. This paper analyzes the relationship between two financial instruments in electricity markets: convergence bidding and congestion revenue rights. Convergence bids allow participants to trade virtual power, whereas congestion revenue rights capture the value of congestion on a transmission line. Both instruments were introduced to solve inefficiencies, however the interaction of these two instruments provides incentives for manipulation. In this work I test whether the financial instruments are being used as intended. The results show that electricity market participants are more likely to hold unprofitable convergence bids on a node where the convergence bid can benefit the value of the congestion revenue rights held at that node. This type of uneconomic convergence bid is consistent with manipulative behavior. I then perform a back of the envelope calculation that shows these potentially manipulative convergence bids create inefficiencies in the market.     

Transmission-constrained oligopoly in the Japanese electricity market

We simulate the Japanese wholesale electricity market as a transmission-constrained Cournot market using a linear complementarity approach. First, we investigate the effects of upgrading the bottleneck transmission line between the eastern and western regions, focusing on the mitigation of transmission congestion. Although increasing the bottleneck capacity would lead to welfare gains, they might not be substantial particularly when transmission capacity costs are taken into account. Second, we examine the effects of splitting the largest electric power company, which is located in the eastern region, focusing on the mitigation of market power. Splitting the largest company into two companies would lead to a 25% reduction in the eastern price, and a 50% reduction in deadweight loss. The divestiture of the largest company would have a significant effect of mitigating market power in the Japanese electricity market.     

Bidding behavior in the Chilean electricity market

Contracts in power markets are usually obscure. From recently public auctions of long-term supply contracts we can obtain information on how contract prices are determined. To understand generators' bidding behavior, this paper examines the Chilean experience from 2006 to 2011. Using a divisible good auction model we provide a theoretical framework that explains bidding behavior in terms of expected spot prices and contracting positions. Empirical estimations indicate heterogeneity in the cost of over-contracting depending on incumbency, bringing evidence of significant barriers to entry.     

Investment incentives in the Korean electricity market

This paper develops a model-based analysis of the effects of various capacity incentive systems on new investment in the Korean electricity market. The restructuring process in Korea allocated power generation to six firms, competing within a wholesale market, albeit strictly on a cost basis. Because of this cost-based pool, capacity payments were also introduced to encourage new investment. However, it is an open question whether the current fixed capacity payment scheme is enough to secure resource adequacy, and consideration is being given to alternative mechanisms such as the use of LOLP. Using a detailed market simulation model, based on system dynamics, we compare these approaches in terms of how they may influence the investors’ decisions and thereby determine the system reserve margin. The simulation results suggest that there may be serious problems in staying with the current fixed capacity payments in order to achieve resource adequacy. In contrast, an LOLP-based capacity mechanism may, in the longer term, increase the reserve margin compared with a fixed capacity payment. More generally, this paper indicates how crucial the effective modeling of the investment behavior of the independent power producers is for adequate policy support, even if they only constitute a fringe in a substantially centrally influenced market.     

Consumers in the green electricity market in Finland

“Green” electricity, i.e. electricity produced from environmentally less harmful sources and marketed as such, has been available to Finnish households since 1998, but the demand for it has remained low. In this paper we discuss the barriers identified by consumers to purchasing green electricity and contrast these with the interpretation energy sector actors give to consumer passivity. The empirical material consists of thematic interviews. Energy policy actors often assume that consumers’ passivity signifies their lack of interest or low environmental consciousness. This results partly from the failure to differentiate between the roles of consumer and citizen. The interpretation the energy sector actors give to consumer passivity and the role they assign to consumers affect the direction of green electricity policy. We argue that consumers need more information on both the environmental impact of different electricity products and in particular about the electricity supply and electricity contracts in a liberalised electricity market if they are to become active in the market.     

Analysis of competition and market power in the wholesale electricity market in India

The electricity reforms were initiated in India with the objective of promoting competition in the electricity market. In order to promote competition, the Electricity Act 2003 was enacted and various policy initiatives were taken by the Government of India. Central Electricity Regulatory Commission (CERC) also facilitated competition through the regulatory framework of availability based tariff, Indian Electricity Grid Code, open access in inter-state transmission, inter-state trading and power exchanges. Despite these initiatives, electricity prices increased in the Wholesale Electricity Market in India (WEMI). This paper analyses the market structure and competitiveness in the WEMI. There are, of course, various potential reasons for the rise in the electricity price. This paper seeks to investigate, if market power was one of the reasons for increase in market prices. Concentration ratio, Herfindahl–Hirschman index, Supply Margin Assessment, and Residual Supply Index have been used to measure market power. This paper also uses the price–cost mark-up to examine, if exercise of market power led to higher margins. The analysis suggests that market power of firms may be part of the reason for the increase in electricity prices in WEMI. The study suggests various measures to increase competition in the WEMI.     

France opens its electricity market

The author describes how the EU Electricity Directive leaves a great deal of freedom to the member states, and details how the opening of the French market is intended to be progressive and controlled