Economic analysis of reserve management strategies for grid-connected wind farms

This paper focuses on the importance of improving the wind power plant's (WPP's) response to the frequency measurable events (FMEs). With the increasing grid penetration levels of wind power, there is a significant need of operating reserves to provide ancillary services such as primary frequency response and thereby improve the power system's reliability. The reserve holding capabilities for the WPP can be created by part loading of one or more turbines in a wind farm (termed as Deloading), as well as through management of excess/un-scheduled energy in storage systems such as battery units (installed at plant level). By controlling this reserve capacity, a governor-like response from the WPP during the FME can be provided. This paper makes an economic comparison of above such reserve management strategies for merchant-based WPP. A Pro Forma financial model has been developed to perform case-by-case quantitative comparison of such strategies, as well as to analyse the sensitivity of various parameters on the power plant economics. Using the model, the scenario which yields the highest value of net present value and internal rate of return is chosen as best one for the provision of primary control reserves.