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Title: Analysis of operating reserve demand curves in power system operations in the presence of variable generation

The electric power industry landscape is continually evolving. As emerging technologies such as wind and solar generating systems become more cost effective, traditional power system operating strategies will need to be re-evaluated. The presence of wind and solar generation (commonly referred to as variable generation or VG) can increase variability and uncertainty in the net-load profile. One mechanism to mitigate this issue is to schedule and dispatch additional operating reserves. These operating reserves aim to ensure that there is enough capacity online in the system to account for the increased variability and uncertainty occurring at finer temporal resolutions. A new operating reserve strategy, referred to as flexibility reserve, has been introduced in some regions. A similar implementation is explored in this study, and its implications on power system operations are analyzed. Results show that flexibility reserve products can improve economic metrics, particularly in significantly reducing the number of scarcity pricing events, with minimal impacts on reliability metrics and production costs. Furthermore, the production costs increased due to increased VG curtailment - i.e. including the flexible ramping product in the commitment of excess thermal capacity that needed to remain online at the expense of VG output.
 [1] ;  [2] ;  [3] ;  [4] ;  [5]
  1. National Renewable Energy Lab. (NREL), Golden, CO (United States)
  2. Univ. of Denver, Denver, CO (United States)
  3. Electric Power Research Institute, Knoxville, TN (United States)
  4. General Electric Energy Consulting, Schenectady, NY (United States)
  5. Kansas State Univ., Manhattan, KS (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 1752-1416
Grant/Contract Number:
Accepted Manuscript
Journal Name:
IET Renewable Power Generation
Additional Journal Information:
Journal Volume: 11; Journal Issue: 7; Journal ID: ISSN 1752-1416
Institution of Engineering and Technology (IET)
Research Org:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Solar Energy Technologies Office (EE-4S)
Country of Publication:
United States
24 POWER TRANSMISSION AND DISTRIBUTION; operating reserve; flexibility reserve; variable generation; variability; uncertainty; reliability; capacity
OSTI Identifier: