Increasing thermal plant flexibility in a high renewables power system

• Published in: Applied energy Vol. 154; pp. 102 - 111
• Main Authors: Kubik, M.L., Coker, P.J., Barlow, J.F.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 15.09.2015
• Subjects: Conventional generation; Flexibility; Intermittency; Ramping; Variability; Wind curtailment; Ramping; Wind curtailment; Flexibility; Variability; Intermittency; Conventional generation
• ISSN: 0306-2619; 1872-9118
• DOI: 10.1016/j.apenergy.2015.04.063

•Insufficient attention is given to potential flexibility of existing thermal plants.•High penetrations of variable renewable generation create curtailment and ramping challenges.•Strategies to reduce variability impacts using existing generation are identified.•Fuel switching can accommodate more renewable generation and improve system ramping capability. Thermal generation is a vital component of mature and reliable electricity markets. As the share of renewable electricity in such markets grows, so too do the challenges associated with its variability. Proposed solutions to these challenges typically focus on alternatives to primary generation, such as energy storage, demand side management, or increased interconnection. Less attention is given to the demands placed on conventional thermal generation or its potential for increased flexibility. However, for the foreseeable future, conventional plants will have to operate alongside new renewables and have an essential role in accommodating increasing supply-side variability. This paper explores the role that conventional generation has to play in managing variability through the sub-system case study of Northern Ireland, identifying the significance of specific plant characteristics for reliable system operation. Particular attention is given to the challenges of wind ramping and the need to avoid excessive wind curtailment. Potential for conflict is identified with the role for conventional plant in addressing these two challenges. Market specific strategies for using the existing fleet of generation to reduce the impact of renewable resource variability are proposed, and wider lessons from the approach taken are identified.