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An inevitable consequence of the power system transition towards nearly 100% inverter-based resources is the loss of synchronous generators with their associated inertia, frequency, and voltage control mechanisms. Battery energy storage with different converter technologies, due to their fast-ramping capabilities, are expected to address these challenges and replicate functionalities that so far have been provided by conventional generators. This article presents an in-depth dynamic analysis for the impact of grid forming and grid following battery energy storage locations on the frequency metrics. Performance comparisons that account for the interactions between storage technologies and the decrease of regional inertia are also investigated via dynamic simulations for the projected 90% inverter-based generations in Ireland in 2030. The analysis is conducted using a high-fidelity model of the 39 bus system, which was modified in DIgSILENT, to best replicate a real frequency event that occurred in the Irish power system. Finally, the empirical findings provide a new understanding of the optimal placement of grid-scale fast storage technologies to maintain power system security at high renewables. [ABSTRACT FROM AUTHOR]

This paper studies the impact of wind generation on system costs and prices in Ireland. The importance of wind power and potential impacts on system costs is of interest to power system planners and policy makers globally. However, the impact of wind generation on system costs has been only studied with limited actual data from power systems with increased wind penetration. The paper uses a unique dataset of half-hourly system demand, generation, forecast and actual wind generation, along with Irish system marginal price (SMP) data from 2008 to autumn 2012. An econometric time-series model of SMP as a function of forecast and realized demand and wind generation yields results which suggest that each 1% increase in wind generation reduces SMP in Ireland by about 0.06%, while each 1% wind forecast error increases SMP about 0.02%. In absolute terms, though, at the mean the impact of wind forecast errors is small, or about 0.4€cent/MWh-wind generated. [ABSTRACT FROM AUTHOR]

Synchronous island power systems, such as the combined Ireland and Northern Ireland power system, are facing increasing penetrations of renewable generation. As part of a wider suite of studies, performed in conjunction with the transmission system operators (TSOs) of the All-Island system (AIS), the frequency stability challenges at high and ultra-high wind penetrations were examined. The impact of both largest infeed loss and network fault induced wind turbine active power dips was examined: the latter contingency potentially representing a fundamental change in frequency stability risk. A system non-synchronous penetration (SNSP) ratio was defined to help identify system operational limits. A wide range of system conditions were studied, with results showing that measures such as altering ROCOF protection and enabling emulated inertia measures were most effective in reducing the frequency stability risk of a future Ireland system. [ABSTRACT FROM AUTHOR]

Although wave power installations are currently limited in number, the capacity value of wave power is of interest in power system planning. The capacity value of wind power has been studied in previous work, but the value for wave power is not known. Continuous time series characterizing the wave energy resource at multiple sites are generated from raw wave data. These time series are analyzed with a forced outage rate imposed for individual devices, as may be encountered by real wave energy farms. The capacity value of wave power at various sites is evaluated with reference to 500 MW of installed capacity. Portfolios are created, allocating wave power capacity to individual sites, with the impact of geographical aggregation being examined. The inter-annual variation for each portfolio is then determined in order to examine the robustness of the results. Comparison is also made between sites off the west coasts of Ireland and Portugal. The implications for the power system resulting from an increase in generation adequacy are discussed. [ABSTRACT FROM PUBLISHER]

A stochastic mixed integer linear optimization scheduling model minimizing system operation costs and treating load and wind power production as stochastic inputs is presented. The schedules are updated in a rolling manner as more up-to-date information becomes available. This is a fundamental change relative to day-ahead unit commitment approaches. The need for reserves dependent on forecast horizon and share of wind power has been estimated with a statistical model combining load and wind power forecast errors with scenarios of forced outages. The model is used to study operational impacts of future high wind penetrations for the island of Ireland. Results show that at least 6000 MW of wind (34% of energy demand) can be integrated into the island of Ireland without significant curtailment and reliability problems. [ABSTRACT FROM AUTHOR]

The capacity value of wind power indicates the extent to which wind power contributes to the generation system adequacy of a power system. The related data requirements may be subject to difficulties due to the temporal variability and spatial distribution of wind power in connection with the limited databases currently available. This paper presents a methodology to identify the minimal amount of data required for reliable studies. Based on wind power data of 74 stations in Ireland, covering up to ten years, the effects of different numbers of stations and different time periods of data on the capacity value are analyzed. The calculations are performed by means of a fast calculation code. The results show that at least four to five years of data in an hourly resolution are necessary for reliable studies and that 40 to 50 evenly distributed stations give an acceptable representation of the total wind power generation in Ireland. [ABSTRACT FROM AUTHOR]