To respond to the ongoing need for efficiency improvement, new balancing arrangements are introduced by the European Network Transmission System Operators of Electricity (ENTSO-E), where transmission system operators (TSOs) cooperate secondary load frequency control (LFC) to reduce both reserve activation and procurement. The latter should, however, not result in inconsistent and disproportional reserve sizing and allocation, which might be the result of the defined cooperation requirements in the Network Code of ENTSO-E. Over-procurement might limit balancing efficiency and under-procurement may jeopardize frequency quality. To investigate such unwanted consequences, two cooperation-concepts are assessed and evaluated in this work for a case study of Central West Continental Europe, namely TSOs sharing its reserves and merging of multiple areas into a common larger LFC Block. Results show that reserve requirements for single areas cannot be directly applied for area cooperation. Especially for the merging of areas into one larger area, current reserve procurement requirements will lead to a relative small amount of procured reserves, which might be risky if no other reserves are available parallel to the merit-order list. For the reserve allocation process, an approach is used to reduce the need of fast-response reserves. Therefore, a signal decomposition technique Hilbert-Huang Transform is used to separate the need for balancing energy into slow and fast-periodic components per area. Results show that the amount of fast-response reserves might be reduced significantly per area. (C) 2015 Elsevier B.V. All rights reserved.

Current developments in generation portfolios and market design urge the need to attract additional balancing services in the form of frequency restoration reserves (FRR). This work elaborates on the opportunities and constraints of current balancing markets in the Netherlands and Germany to harness the profitability and feasibility of energy storage systems to participate in load-frequency control and in FRR in particular. One of the main concerns of storage is the state of charge, i.e. availability of discharging or charging energy respectively. Even though firm capacity needs to be provided, the Dutch market allows bids to be withdrawn up to one hour ahead of operation. Therefore Energy Storage System participation in the frequency restoration process encounters limited risk compared to the case of the German system. Furthermore, the Dutch system allows passive balancing, where Energy Storage Systems can contribute in an opportunistic fashion without the need for firm contracts.

Increasing levels of wind power generation in the coming years will displace conventional generation, impacting the need for balancing reserves. The upcoming integration of pan-European balancing markets seeks to increase collaboration between areas for optimal provision of services. The challenge of increased variability due to wind and other renewables could be tackled by the exchange of balancing services among regional groups within the larger interconnected system. In this work, load-frequency control models of the United Kingdom and Continental Europe were developed in the MATLAB/Simulink environment and a worst-case event for the UK in the year 2020 is chosen for analysis. Fast control actions are then exchanged between the power systems of UK and Continental Europe. The performance of the coupled system in terms of frequency deviation is evaluated and compared to the decoupled situation. The results show that the frequency response improves, with lower maximum deviations. A cross-border balancing arrangement also leads to less deployment of reserves for UK.

Variability and predictability constraints of wind hinder the cost-efficient integration of wind power generation into power markets. Within the framework of EIT KIC INNOENERGY Offwindtech project, a ‘Market Value’ tool is developed. Here, the market value of wind power generation can be assessed with respect to its wind site and the respective power market it is integrated in. A case study is introduced to compare the potential market value of different wind sites (offshore/onshore) and of different power market concepts (day ahead/intra-day). It is found that the relative market value of wind power does not significantly differ between its diverse conditions. Nevertheless, when considering the costs of wind power generation, coastal wind power generation, to be sold in intra-day markets, has the largest potential to be cost-efficient. Future reduction of offshore installation and maintenance cost could further increase the market value/competition of offshore wind power. The difference of predictability accuracy between onshore and offshore wind power generation has negligible impact on the results

In many power systems like for instance the Continental European synchronous area of the ENTSO-E, wind power is replacing conventional (thermal) generation. Because wind power does in general not show inertial response and does not provide control power, the ability of the entire system to withstand power disturbances deteriorates. Under the event of a large generation outage in a system with large scale wind power, grid frequency limits could be exceeded which affect controllability, stability, and reliability of power system operation. Therefore, there is an incentive that wind turbines participate in balancing power. Previous research showed that control systems can enable participation of wind turbines in balancing, using their kinetic energy. It was also perceived that different sized wind turbines have different capacities to support the system. This research elaborates on previous work and shows that wind turbines equipped with adequate control systems can provide nearly identical grid frequency response as conventional power plants, independently of the size of the wind turbines. This work shows that system stability can be maintained even with large scale wind power integration. The grid frequency drop which immediately originates after a large generation outage will not worsen due to wind power, which consequently will not threaten the current power system operation.

Socio-economical and technological developments have prompted electric power systems to move forward to an era of Smart Grids. This mainstream concept has a strong interdisciplinary nature by using state-of-the-art technologies in the fields of Information and Communication Technology (ICT), power electronics, and control systems. Modeling and simulation are fundamental steps to accomplish possible applications of this complex and integrated scheme. However, most of the existing simulation platforms, either commercial or free and open source packages, hardly adapt to this requirements of Smart Grids. This paper presents an on-going framework which integrates open source software, OpenDSS, to provide different web services for end-users. This application aims to create a robust computation platform to support customers in making decisions. Different network functions can be verified in this assessment context tool. Working as a social network, this program will empower end-users with an interaction interface to make them fully aware of Smart Grid applications.

Future's penetration of more distributed generation will have an effect on the power system's stability and controllability. In general, wind power as a distributed generator does not have inertial response and does not supply control power. A third characteristic of wind power is that it is not conventionally controlled and its main resource is fluctuating. This paper describes a methodology to calculate wind power fluctuations in the frequency domain to compare it with load fluctuations for higher frequency power fluctuations. In relation, the approach of wind power smoothing is mentioned to mitigate the grid impact of power fluctuations. To smooth power, the concept of inertial wind power smoothing is briefly discussed for the low wind speed range of wind turbines, between the cut-in and rated wind speed. A smart grid could be equipped with a control system to control the power output of wind turbines and wind farms to mitigate the grid impact of wind power fluctuations on the frequency stability of a power system.

Wind fluctuations result in even larger wind power fluctuations because the power of wind is proportional to the cube of the wind speed. This report analyzes wind power fluctuations to investigate inertial power smoothing, in particular for the frequency range of 0.08 - 0.5 Hz. Due to the growing penetration rate of wind power, the susceptibility of the power system to power fluctuations increases. Wind turbines operating at a higher rotational speed compared to optimal tip speed ratio's have the ability to smooth power. However, the efficiency of a wind turbine with inertial power smoothing capabilities will be lower. Full inertial power smoothing for fluctuations of 0.01Hz and higher will decrease the overall wind turbines efficiency with less than 1.5%.