Methodologies to determine operating reserves due to increased wind power

Abstract

Power systems with high wind penetration experience increased variability and uncertainty, such that determination of the required additional operating reserve is attracting a significant amount of attention and research. This paper presents methods used in recent wind integration analyses and operating practice, with key results that compare different methods or data. Wind integration analysis over the past several years has shown that wind variability need not be seen as a contingency event. The impact of wind will be seen in the reserves for non-event operation (normal operation dealing with deviations from schedules). Wind power will also result in some events of larger variability and large forecast errors that could be categorized as slow events. The level of operating reserve that is induced by wind is not constant during all hours of the year, so that dynamic allocation of reserves will reduce the amount of reserves needed in the system for most hours. The paper concludes with recent emerging trends

A New Required Reserve Capacity Determining Scheme with Regard to Real time Load Imbalance

“…However, the output power fluctuation of renewable resources may cause excess fluctuations of the demand due to the variation of wind speed and sunshine intensity. [6,7] Therefore, power systems with high distributed generator penetration experience increased variability and uncertainty, such that new method to determine the required operating reserve is needed.…”

“…Their power fluctuations on the grid leads to large demand volatility, therefore it is not reasonable to decide operating reserves at fixed value. [6,7] Moreover, abnormal temperature cause the imbalance of demand in now and future power system. For these reasons, SO should be determined to apply real time response operating reserves capacity rather than fixed operating reserves capacity.…”

Scenario selection of wind forecast errors for stochastic unit commitment: A UK case study

“…Moreover, the probability of each scenario ( ) is pondered along with the Euclidean distance, owing to unlikely scenarios are prone to be delated (3). Once the decision is made regarding the scenario that is deleted, the next step is to update the probability of the nearest scenario ( ) by adding the probability of the discarded scenario ( ) , see equation (4). Then, the total number of scenarios changes (e.g.…”

“…Therefore, definition of reserves is fundamental to absorb deviations between forecast and actual values in a cost-effective manner. In a first approach, deterministic models apply statistical analysis of the net demand to assign a fix value of reserve (3-σ Method) [4]. In the UK system, National Grid assigns reserves as a percentage of the most recent foresight, for instance; if wind production is greater than 1500MW, the amount of reserve should be 10% of the corresponding prediction in the next half hour [5].…”

Wind Integration into Energy Systems with a High Share of Nuclear Power—What Are the Compromises?

“…The impact of large-scale wind penetration on a power system has been subject for a wide spectrum of researches in the literature; on the need for operating reserves [12], unit commitment [13], balancing power [14], and transmission system planning [15]. This study aims to investigate this impact on the entire energy system in an integrated method by considering the potential of both heat and power sectors in absorbing fluctuating RES intersected with the nuclear power.…”