Fossil fleet transition with fuel changes and large scale variable renewable integration

Technical Report · Tue Mar 31 04:00:00 EDT 2015

DOI:https://doi.org/10.2172/1224949· OSTI ID:1224949

James, Revis ^[1]; Hesler, Stephen ^[2]; Bistline, John ^[2]

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1. Electric Power Research Institute, Palo Alto, CA (United States); Electric Power Research Institute, Incorporated
2. Electric Power Research Institute, Palo Alto, CA (United States)

Variability in demand as seen by grid-connected dispatchable generators can increase due to factors such as greater production from variable generation assets (for example, wind and solar), increased reliance on demand response or customer-driven automation, and aggregation of loads. This variability results a need for these generators to operate in a range of different modes, collectively referred to as “flexible operations.” This study is designed to inform power companies, researchers, and policymakers of the scope and trends in increasing levels of flexible operations as well as reliability challenges and impacts for dispatchable assets. Background Because there is rarely a direct monetization of the value of operational flexibility, the decision to provide such flexibility is typically dependent on unit- and region-specific decisions made by asset owners. It is very likely that much greater and more widespread flexible operations capabilities will be needed due to increased variability in demand seen by grid-connected generators, uncertainty regarding investment in new units to provide adequate operational flexibility, and the retirement of older, uncontrolled sub-critical pulverized coal units. Objective To enhance understanding of the technical challenges and operational impacts associated with dispatchable assets needed to increase operational flexibility and support variable demand. Approach The study approach consists of three elements: a literature review of relevant prior studies, analysis of detailed scenarios for evolution of the future fleet over the next 35 years, and engineering assessment of the degree and scope of technical challenges associated with transformation to the future fleet. The study approach integrated two key elements rarely brought together in a single analysis—1) long-term capacity planning, which enables modeling of unit retirements and new asset investments, and 2) unit commitment analysis, which permits examination of hourly unit dispatch while considering operational limitations relevant to flexible operations capabilities.

• Research Organization: Electric Power Research Institute, Palo Alto, CA (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: OE0000614
• OSTI ID: 1224949
• Country of Publication: United States
• Language: English