Duke Indiana 2021 Integrated Resource Plan

Synapse supported Sierra Club's engagement in Duke Indiana's 2021 IRP process. Synapse participated in the utility's year-long stakeholder process and supported Sierra Club in drafting multiple comment letters throughout the process. We examined Duke's Encompass modeling results and assumptions with a focus on its retirement plans for its coal fleet. We found that the company's modeling process neglected to robustly consider timely retirement of its coal resources and replacement with clean alternatives. Most concerning was the company's decision to continue operating the Edwardsport integrated gasification combined cycle facility on coal rather than converting to full-time gas operation.