June 25th, 2021: Back in December of 2020, Dominion's 2020 Integrated Resource Plan (IRP) was unanimously rejected by the South Carolina Public Service Commission. The commission ordered Dominion to submit a new Modified IRP, announced plans to open a coal retirement docket, and specifically required the utility to begin studying coal retirements immediately. Dominion submitted its Modified 2020 IRP in February, which came to a much different conclusion than its original IRP - that the retirement of the Wateree and Williams Coal Plants by 2028 was now the preferred path for the Company. Sierra Club, along with fellow intervenors South Carolina Coastal Conservation League, Southern Alliance for Clean Energy and the South Carolina Solar Business Alliance submitted joint comments to the Commission, agreeing with Dominion that the least cost, best path forward was to retire the 2124 megawatts of coal-fired generation, but that Dominion was still falling short in its analysis of near-term renewables such as solar, wind and storage.
Last week, the Commission unanimously approved Dominion's modified IRP and its accelerated coal retirement plan: Wateree and Williams will close by 2028 (and a third coal plant, Cope, will switch to gas-only by 2030), resulting in the potential retirement of 2124 megawatts of coal-fired generation. In addition to approving the coal retirement plan, the Commission also imposed upon Dominion additional items that they must include in its 2021 IRP Update, to be filed in August. To name a few, Dominion is required to include near-term solar and storage as a resource option in future IRPs, along with the development and an implementation plan for an all-source procurement. This will allow future IRPs to recommend a portfolio of resources using actual bid data.
While not specifically mentioned in the Commission's order, a few days later the Commission unanimously agreed to open a new and separate docket, which will specifically evaluate the reliability risks and environmental costs of continued operation of Wateree and Williams and will also assess the replacement of these coal plants, informed by resource bids, with clean energy, in light of Dominion's plan to move forward with retiring both coal plants.
Find the previous update for this case here.