1. The impact of high levels of renewable generation on conventional fossil fuel based electricity markets
- Author
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Kubik, Marek L.
- Subjects
333.79 - Abstract
The variability of energy supplied from renewable resources is commonly identified as one of the major challenges of integrating renewable energy with existing power systems. With a 40% renewable energy target by 2020, this is a particularly challenging proposition in Northern Ireland, where an ageing and diminishing conventional fossil fuel mix is required to respond to this variability. This research project asked key questions of the suitability of the existing generation in Northern Ireland and identified strategies to minimise the impact of variability and facilitate high levels of renewable integration. Two particular areas of concern were addressed: the level of wind curtailment required to balance electricity supply and demand, and identifying whether the extremes of wind generation variability are technically manageable. This thesis shows the cost and level of wind curtailment are a growing problem in Northern Ireland. By 2020, curtailment of 7-7.S% of annual wind generation is expected under existing security constraints. Analysis of 32 years of wind generation variability has identified that large swings in wind generation are rare, and that 99% of the time they are less than ±S% of installed capacity. However, low frequency, high impact swings in wind generation were found to occur at Smin, I hr and 4hr timescales, to which the system has insufficient flexibility to respond. Twenty-eight unit combinations were ranked by modelling the projected level of wind curtailment and the associated emissions in 2020. This identified scenarios that can reduce wind curtailment and increase resilience to variability, as well as reducing associated CO, emissions and costs. Immediate modifications that could be made to reduce Kilroot power plant's minimum generation level were also assessed. Through modelling different unit combinations against simulated wind generation, certain scenarios where wind curtailment was reduced were found to diminish the system's capability to respond to wind ramping events. In Northern Ir'eland, where conventional units are required to run to maintain system security, appropriate market incentives are needed to encourage operational improvements. This research supports the plans to construct a new tieline to the Republic of Ireland, which should aid in minimising wind curtailment and improving ramping capabilities. Extending the analysis to test the inclusion of battery storage identified that a 100MW unit would significantly improve ramping capabilities, particularly for two unit combinations with lower plant flexibility. This thesis has demonstrated strategies that can be deployed to make variability more manageable. The renewable resource variability in Northern Ireland is as challenging as is technOlogically likely on any fossil fuel based electricity system. This should be a message of considerable encouragement to other fossil fuel based electricity markets, which may have longer to arrive at similar decarbonisation levels, larger pools of conventional generation to call upon, and potentially more technologically diverse and spatially aggregated renewable resources.
- Published
- 2013