Options
Flynn, Damian
Preferred name
Flynn, Damian
Official Name
Flynn, Damian
Research Output
Now showing 1 - 9 of 9
- PublicationPumped Hydro and Compressed Air Energy Storage at High Wind PenetrationsEnergy storage is a widely used tool for balancing power systems and for providing increased operational flexibility - as such it can assist with the integration of variable renewable electricity generation. Grid-scale energy storage provides potential solutions to some of the technical and economic challenges which arise in systems with high penetrations of variable renewables, particularly on isolated systems. However, capital costs per MW are high, which means that variable renewable penetrations must reach significant levels before the operating cost reductions justify the capital expenditure. Optimum levels of grid-scale storage are explored, considering capital costs and potential operational cost savings for two storage technologies - pumped hydroelectric storage and compressed air energy storage. Grid-scale installations are found to achieve significant cost savings, particularly at high levels of wind generation. While the potential for savings is eroded significantly at high levels of DC interconnection, they remain high when non-synchronous penetration limits are increased.
304 - PublicationDynamic frequency control with increasing wind generationFrequency control is essential for the secure and stable operation of a power system. With wind penetration increasing rapidly in many power systems, ensuring continuous power system security is vital. The frequency response to a disturbance on the all Ireland system is simulated for a range of installed wind capacities under different system conditions. The purpose of this study is to assess the effects of increased wind generation on system frequency, and the security of the system following such disturbances
1466 - PublicationMulti-mode operation of combined-cycle gas turbines with increasing wind penetrationAs power systems evolve to incorporate greater penetrations of variable renewables, the demand for flexibility within the system is increased. Combined-cycle gas turbines are traditionally considered as relatively inflexible units, but those which incorporate a steam bypass stack are capable of opencycle operation. Facilitating these units to also operate in opencycle mode can benefit the power system via improved system reliability, while reducing the production needed from dedicated peaking units. The utilization of the multi-mode functionality is shown to be dependent on the flexibility inherent in the system and the manner in which the system is operated.
1089Scopus© Citations 39 - PublicationLoad inertia estimation using white and grey-box estimators for power systems with high wind penetration(Elsevier - International Federation of Automatic Control (IFAC), 2012-09-02)
; ; ; The increasing penetration of wind farms in power systems has increased concerns over the frequency behaviour and control of synchronous power systems due to a low contribution from modern wind turbines to overall system inertia. With this trend of conventional generators being displaced by variable speed wind turbines, the contribution from load inertia becomes more significant. The need for greater consideration towards load inertia estimation, or even on-line tracking of load inertia, seems to be required. A white-box method for estimation of load inertia is examined using system frequency and generator output power signals from previous generator forced outages. A grey-box identification method is also applied to estimate the inertia of synchronous generators. The impact of sampling rates, time shifting and signal averaging on parameter estimation is also considered. The method is shown to be robust enough to be applied for load inertia estimation in control centres.982Scopus© Citations 24 - PublicationChallenges posed by the integration of wave power onto the Irish power system(2011-09-05)
; ; In order to gauge the potential impact of wave power in Ireland, the capacity factor of theoretical wave farms deployed at various locations around the Irish coast is compared to the system-wide capacity factor of wind power generation over the same period. It is shown that wave power off the coast of Ireland experiences a very significant seasonal variation, but with a lower daily variation. This paper presents the results of that analysis and examines certain challenges that will face the Irish power system if a large portfolio of wave power devices is deployed. Issues such as system adequacy and the capacity value of wave power are discussed.410 - PublicationEmissions from cycling of thermal power plants in electricity systems with high penetration of wind power: Life cycle assessment for IrelandThe increase of renewable sources in the power sector is an important step towards more sustainable electricity production. However, introducing high shares of variable renewables, such as wind and solar, cause dispatchable power plants to vary their output to fulfill the remaining electrical demand. The environmental impacts related to potential future energy systems in Ireland for 2025 with high shares of wind power were evaluated using life cycle assessment (LCA), focusing on cycling emissions (due to part-load operation and start-ups) from dispatchable generators. Part-load operations significantly affect the average power plant efficiency, with all units seeing an average yearly efficiency noticeably less than optimal. In particular, load following units, on average, saw an 11% reduction. Given that production technologies are typically modeled assuming steady-state operation at full load, as part of LCA of electricity generation, the efficiency reduction would result in large underestimation of emissions, e.g. up to 65% for an oil power plant. Overall, cycling emissions accounted for less than 7% of lifecycle CO2, NOx and SO2 emissions in the five scenarios considered: while not overbalancing the benefits from increasing wind energy, cycling emissions are not negligible and should be systematically included (i.e. by using emission factors per unit of fuel input rather than per unit of power generated). As the ability to cycle is an additional service provided by a power plant, it is also recommended that only units with similar roles (load following, mid merit, or base load) should be compared. The results showed that cycling emissions increased with the installed wind capacity, but decreased with the addition of storage. The latter benefits can, however, only be obtained if base-load electricity production shifts to a cleaner source than coal. Finally, the present study indicates that, in terms of emission reductions, the priority for Ireland is to phase out coal-based power plants. While investing in new storage capacity reduces system operating costs at high wind penetrations and limits cycling, the emissions reductions are somewhat negated when coupled with base load coal.
985Scopus© Citations 70 - PublicationTechnical impacts of high penetration levels of wind power on power system stabilityWith increasing penetrations of wind generation, based on power-electronic converters, power systems are transitioning away from well-understood synchronous generator-based systems, with growing implications for their stability. Issues of concern will vary with system size, wind penetration level, geographical distribution and turbine type, network topology, electricity market structure, unit commitment procedures, and other factors. However, variable-speed wind turbines, both onshore and connected offshore through DC grids, offer many control opportunities to either replace or enhance existing capabilities. Achieving a complete understanding of future stability issues, and ensuring the effectiveness of new measures and policies, is an iterative procedure involving portfolio development and flexibility assessment, generation cost simulations, load flow, and security analysis, in addition to the stability analysis itself, while being supported by field demonstrations and real-world model validation.
Scopus© Citations 69 1544 - PublicationDemand side resource operation on the Irish power system with high wind power penetration(Elsevier, 2011-05)
; ; ; ; ; ; The utilisation of demand side resources is set to increase over the coming years with the advent of advanced metering infrastructure, home area networks and the promotion of increased energy efficiency. Demand side resources are proposed as an energy resource that, through aggregation, can form part of the power system plant mix and contribute to the flexible operation of a power system. A model for demand side resources is proposed here that captures its key characteristics for commitment and dispatch calculations. The model is tested on the all island Irish power system, and the operation of the model is simulated over one year in both a stochastic and deterministic mode, to illustrate the impact of wind and load uncertainty. The results illustrate that demand side resources can contribute to the efficient, flexible operation of systems with high penetrations of wind by replacing some of the functions of conventional peaking plant. Demand side resources are also shown to be capable of improving the reliability of the system, with reserve capability identified as a key requirement in this respect.997Scopus© Citations 69 - PublicationEvolution of operating reserve determination in wind power integration studies(IEEE, 2010-07)
; ; ; ; ; ; The growth of wind power as an electrical power generation resource has produced great benefits with reductions in emissions and the supply of zero cost fuel. It also has created challenges for the operation of power systems arising from the increased variability and uncertainty it has introduced. A number of studies have been performed over the past decade to analyze the operational impacts that can occur at high penetrations of wind. One of the most crucial impacts is the amount of incremental operating reserves required due to the variability and uncertainty of wind generation. This paper describes different assumptions and methods utilized to calculate the amount of different types of reserves carried, and how these methods have evolved as more studies have been performed.1321Scopus© Citations 116