Impact of wind generation control strategies, penetration level and installation location on electricity market prices

Integration of wind facilities into power system grids have several impact on power system related issues including; transmission congestion, optimum power flow, system stability, power quality, system economics and load dispatch. Consequently, wind farm control strategy, location across the distribution network and its penetration level could have an impact on electricity market prices. This paper addresses these issues, by developing a single auction market model. An optimal power flow problem was formulated for determining the close to real time electricity market-clearing price and the total cost of generation. Simulation results, considering different operational cases, are presented to highlight the impact.     

风电场并网对电力系统的影响分析

风电场输出功事的间歇性和波动性,给系统的电能质量、稳定运行等造成了严重的影响,成为制约风电场发展的重要因素.从风力发电的特点入手,分析了风电场并网对系统正常运行造成的影响,提出了一些相应的改善措施.     

RES support in Russia: Impact on capacity and electricity market prices

Russian renewable energy policy has undergone changes following an establishment of targets for installed capacity and power production using renewable energy sources and the introduction of new capacity based support scheme for renewable energy. The forecasted amount of future renewable power will not provide enough power production to meet growing demand for renewable energy; although, it will help with modernization of the energy sector and development of renewable technology and innovation. At the same time, the capacity support scheme for renewable energy may adversely affect capacity prices and become an additional burden for industrial consumers, who are already paying the cost of capacity support for conventional power plants, so-called Capacity Delivery Agreements (CDAs). This work assesses the impact of the new capacity based support scheme on capacity and electricity price formation. Modeling results show that the impact of capacity support for renewable energy is small compared to that of capacity support for conventional energy, suggesting that the Russian energy production mix will continue to be dominated by fossil fuel based generation.     

Analysis of demand response and wind integration in Germany's electricity market

Demand response represents an additional option for reserve capacity as first market experiences have demonstrated. An analysis for Germany shows capacities up to 3 GW and costs starting at 30 euro/MWh in the industrial sector, 8 GW in the commercial sector and more than 20 GW in the residential sector including night storage heating. Simulations of the German power system showed that using these potentials together with improved wind power predictions can limit the additional balancing costs in Germany to below 2 euro/MWh feed-in by wind turbines with 48 GW wind power in 2020.     

High penetration wind generation impacts on spot prices in the Australian national electricity market

This paper explores wind power integration issues for the South Australian (SA) region of the Australian National Electricity Market (NEM) by assessing the interaction of regional wind generation, electricity demand and spot prices over 2 recent years of market operation. SA's wind energy penetration has recently surpassed 20% and it has only a limited interconnection with other regions of the NEM. As such, it represents an interesting example of high wind penetration in a gross wholesale pool market electricity industry. Our findings suggest that while electricity demand continues to have the greatest influence on spot prices in SA, wind generation levels have become a significant secondary influence, and there is an inverse relationship between wind generation and price. No clear relationship between wind generation and demand has been identified although some periods of extremely high demand may coincide with lower wind generation. Periods of high wind output are associated with generally lower market prices, and also appear to contribute to extreme negative price events. The results highlight the importance of electricity market and renewable policy design in facilitating economically efficient high wind penetrations.     

The impact of wind power on electricity prices

This paper investigates the impact of wind power on electricity prices using a production cost model of the Independent System Operator – New England power system. Different scenarios in terms of wind penetration, wind forecasts, and wind curtailment are modeled in order to analyze the impact of wind power on electricity prices for different wind penetration levels and for different levels of wind power visibility and controllability. The analysis concludes that electricity price volatility increases even as electricity prices decrease with increasing wind penetration levels. The impact of wind power on price volatility is larger in the shorter term (5-min compared to hour-to-hour). The results presented show that over-forecasting wind power increases electricity prices while under-forecasting wind power reduces them. The modeling results also show that controlling wind power by allowing curtailment increases electricity prices, and for higher wind penetrations it also reduces their volatility.     

美国加州电力市场电价的分形特征

以美国加州电力市场长期电价序列为研究对象，并由此引入了分数布朗运动模型和R／S分析法，计算出了不同时间区间内电价的赫斯特指数，发现加州电力市场符合分形市场假设，电价遵循有偏的随机游走．具有长期相关性和统计自相关性等性质。这些发现为描述市场环境下的电价分布提供了一种新模式。     

Optimal electricity market for wind power

This paper is about electricity market operation when looking from the wind power producers’ point of view. The focus in on market time horizons: how many hours there is between the closing and delivering the bids. The case is for the Nordic countries, the Nordpool electricity market and the Danish wind power production. Real data from year 2001 was used to study the benefits of a more flexible market to wind power producer. As a result of reduced regulating market costs from better hourly predictions to the market, wind power producer would gain up to 8% more if the time between market bids and delivery was shortened from the day ahead Elspot market (hourly bids by noon for 12–36 h ahead). An after sales market where surplus or deficit production could be traded 2 h before delivery could benefit the producer almost as much, gaining 7%.     

Effect of increased wind penetration on system prices in Korea's electricity markets

In this paper, we examine the effect of increased wind penetration on system marginal prices (SMPs) in South Korea's electricity market. Korea's renewable portfolio standard (RPS) went into effect in 2012, with a goal of increasing the share of renewable generation to 10% of the total load by 2022. We examine the output of wind installations across the Korean peninsula and simulate an increase in wind penetration consistent with Korea's RPS targets. Under a variety of assumptions on demand elasticity, we find that higher shares of wind generation in total supply reduce both the average SMP and its variation. In particular, we find that wind energy output on the Korean peninsula is more correlated with peak electricity demand than has been reported for other regions. The per‐unit value of wind energy to owners of wind assets is thus higher for South Korea than would be the case for European or North American locations with a similar mix of fuels other than wind. Copyright © 2013 John Wiley & Sons, Ltd.     

A dynamic network analysis of spot electricity prices in the Australian national electricity market

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.     

Influence of the pro-ecological tax on the market prices of fuels and electricity

The proposed pro-ecological tax should be proportional to the cumulative consumption of non-renewable natural exergy burdening the considered product. It should replace the existing value-added tax (VAT). The income of the state after introducing the new tax, should remain without any change. That principle determines the coefficient of proportionality between the cumulative consumption of non-renewable exergy and the value of the tax. The total value of the tax should be paid to the state after extracting the minerals and fuels from nature and importing the fuels and semi-finished products, then transferred to the subsequent products in a form of their elevated price. Hence, the tax is eventually paid by the consumers in the form of an elevated price of goods and services. The total income of the society should remain without any changes. The largest price increase will appear in the case of fuels and electricity. The prices of electricity produced from renewable resources are calculated too, taking into account the accompanying unavoidable consumption of non-renewable exergy for the construction of the power plant. The new VAT should enhance the economy of the most energy-consuming products, stimulate the mitigation of the total consumption level of the society and increase the application of the renewable energy resources.     

Impact of FACTS devices on exercising market power in deregulated electricity market

In power system studies, congestion in transmission lines and utilization of flexible alternating current transmission system (FACTS) devices are closely associated. These devices are very important due to their role in power delivery system enhancement. It is to be noted that the generation companies can exercise their market power which depends on the line flows, line constraints, generators’ location and its share to the individual loads. This issue cannot be overlooked as it creates monopoliness which is against the deregulated market policy. The objective of this paper is to study the impact of market power when FACTS devices like thyristor controlled switching capacitor (TCSC) and thyristor controlled phase angle regulator (TCPAR) are used under steady state operation. The market power is determined using nodal must-run share (NMRS) index for the standard IEEE 14-bus system with and without the above FACTS devices and the results obtained are compared. All the above simulations are conducted in a MATLAB 7.9-R2009b environment.     

Impacts of day-ahead versus real-time market prices on wholesale electricity demand in Texas

The somewhat recent nodal market structure in Texas impacts wholesale day-ahead market (DAM) and real-time market (RTM) prices. However, comparative insights on consumer responses to both these prices have not received attention. This paper attempts to fill this void by developing a system-wide demand response model to better understand price elasticities under DAM and RTM pricing. These insights may also assist grid operators to develop improved short-term forecasts of electricity demand. Using a large dataset from the Electric Reliability Council of Texas and a hierarchical Bayesian population model, we offer new insights on how DAM and RTM pricing shapes demand for electricity, and the related consequences for maintaining a reliable electricity market.     

Investing in vertical integration: electricity retail market participation

Electricity industries are frequently characterised by a high degree of vertical integration. We explore the option for a generator to enlarge its participation in the retail market, and show that the firm will choose to delay if market demand is too high or low. In the former case, high wholesale prices may make fixed price retail customers unattractive, while in the latter, too little revenue is earned to justify the option's expense. Increased volatility can, under some circumstances, lower the value of the option, contrary to conventional real options theory. Firms expand their retail positions more aggressively in concentrated markets, vertically integrated markets, and markets where financial hedging is prevalent.     

Comparative analysis of features of Polish and Lithuanian Day-ahead electricity market prices

The goal of this article is to better understand the processes of electricity market price formation in Poland and Lithuania through an analysis of the features (volatility and spikes) of Lithuanian and Polish day-ahead electricity market prices and to assess how acquired electricity price features could affect the achievement of the main goals of the national energy policy. The following indicators have been calculated to determine electricity market price volatility: the oscillation coefficient, the coefficient of variation, an adjusted coefficient of variation, the standard deviation indicator, the daily velocity indicator (based on the overall average price) and the daily velocity indicator (based on the daily average price). Critical values for electricity market price have been calculated to evaluate price spikes. This analysis reveals that electricity market-price volatility is moderate in Poland and high in Lithuania. Electricity price spikes have been an observable phenomenon both in Lithuanian and in Polish day-ahead electricity markets, but they are more common in Lithuania, encompassing 3.15% of the time period analysed in Poland and 4.68% of the time period analysed in Lithuania. Volatile, spiking and increasing electricity prices in day-ahead electricity markets in Lithuania and Poland create preconditions and substantiate the relevance of implementation of the national energy policies and measures.     

Analysing the impact of renewable electricity support schemes on power prices: The case of wind electricity in Spain

It is sometimes argued that renewables are “expensive”. However, although it is generally true that the private costs of renewable electricity generation are certainly above those of conventional electricity, that statement fails to consider the social benefits provided by electricity from renewable energy sources (RES-E), including environmental and socioeconomic ones. This paper empirically analyses an additional albeit usually neglected benefit: the reduction in the wholesale price of electricity as a result of more RES-E generation being fed into the grid. The case of wind generation in Spain shows that this reduction is greater than the increase in the costs for the consumers arising from the RES-E support scheme (the feed-in tariffs), which are charged to the final consumer. Therefore, a net reduction in the retail electricity price results, which is positive from a consumer point of view. This provides an additional argument for RES-E support and contradicts one of the usual arguments against RES-E deployment: the excessive burden on the consumer.     

Integration of wind power in the liberalized Dutch electricity market

Wind power is becoming a large‐scale electricity generation technology in a number of European countries, including the Netherlands. Owing to the variability and unpredictability of wind power production, large‐scale wind power can be foreseen to have large consequences for balancing generation and demand in power systems. As an essential aspect of the Dutch market design, participants are encouraged to act according to their energy programs, as submitted day‐ahead to the system operator. This program responsibility shifts the burden of balancing wind power away from the system operator to the market. However, the system operator remains the responsible party for balancing any generation/load imbalances that may still be arising in real time. In this article, features that are unique for the Dutch market design are presented and their implications on the system integration of wind power are investigated. It is shown that the Dutch market design penalizes the intermittent nature of wind power. A discussion of opportunities and threats of balancing wind power by use of market forces is provided. Last, an outline is given of future work. Copyright © 2006 John Wiley &Sons, Ltd.     

A combined modeling approach for wind power feed-in and electricity spot prices

Wind power generation and its impacts on electricity prices has strongly increased in the EU. Therefore, appropriate mark-to-market evaluation of new investments in wind power and energy storage plants should consider the fluctuant generation of wind power and uncertain electricity prices, which are affected by wind power feed-in (WPF). To gain the input data for WPF and electricity prices, simulation models, such as econometric models, can serve as a data basis.This paper describes a combined modeling approach for the simulation of WPF series and electricity prices considering the impacts of WPF on prices based on an autoregressive approach. Thereby WPF series are firstly simulated for each hour of the year and integrated in the electricity price model to generate an hourly resolved price series for a year. The model results demonstrate that the WPF model delivers satisfying WPF series and that the extended electricity price model considering WPF leads to a significant improvement of the electricity price simulation compared to a model version without WPF effects. As the simulated series of WPF and electricity prices also contain the correlation between both series, market evaluation of wind power technologies can be accurately done based on these series.     

Forecasting electricity spot market prices with a k-factor GIGARCH process

In this article, we investigate conditional mean and conditional variance forecasts using a dynamic model following a k-factor GIGARCH process. Particularly, we provide the analytical expression of the conditional variance of the prediction error. We apply this method to the German electricity price market for the period August 15, 2000–December 31, 2002 and we test spot prices forecasts until one-month ahead forecast. The forecasting performance of the model is compared with a SARIMA–GARCH benchmark model using the year 2003 as the out-of-sample. The proposed model outperforms clearly the benchmark model. We conclude that the k-factor GIGARCH process is a suitable tool to forecast spot prices, using the classical RMSE criteria.     

Industrial customer response to wholesale prices in the restructured Texas electricity market

This paper estimates the demand responsiveness of the 20 largest industrial energy consumers in the Houston area to wholesale price signals in the restructured Electric Reliability Council of Texas (ERCOT) market. Statistical analysis of their load patterns employing a Symmetric Generalized McFadden cost function model suggests that ERCOT achieved limited success in establishing a market that facilitates demand response from the largest industrial energy consumers in the Houston area to wholesale price signals in its second year of retail competition. The muted price response is at least partially because energy consumers who opt to offer their “interruptibility” to the market as an ancillary service are constrained in their ability to respond to wholesale energy prices.