Review of Duke Indiana Unit Commitment and Dispatch Practices in the Company’s Quarterly Fuel Adjustment Cost Dockets


Synapse is providing expert testimony and analysis to support Sierra Club in Duke Energy Indiana’s Fuel Adjustment Cost (FAC) dockets for the period of September 2019 through May 2020.

Synapse is evaluating the unit commitment and dispatch practices for Duke’s four coal plants at Edwardsport, Cayuga, Gibson, and Gallagher as part of the Company’s regular Fuel Adjustment Cost Adjustment (FAC) dockets. We find that Duke has been uneconomically committing most of its units a majority of the time throughout this entire time period. These commitment and dispatch practices were further exacerbated by the Company’s implementation of a fuel price decrement in FAC 125 (March – May 2020) to address the Company’s coal oversupply.

We find that as a result of the Company’s uneconomic commitment and dispatch practices, Duke has accumulated net revenue losses (based on just variable and fuel costs) at most or all of its units during at least one (and in most cases all) of the FAC 123, FAC 124, and FAC 125 periods between September 2019 and May 2020. As a result of our work in FAC 123, the Indiana Utility Regulatory Commission agreed to open a subdocket to examine the issue of unit commitment more closely. Synapse has provided expert support and testimony in all three FAC periods as well as the subdocket.

Project completed February 2021.