In the nearly decade-long saga to regulate greenhouse gas (GHG) emissions from fossil fuel-fired power plants, the U.S. EPA recently began the rulemaking process for a new set of regulations that would impose restrictions on emission units at new and existing power plants. On May 23, the U.S. EPA published a proposed rule titled "New Source Performance Standards for Greenhouse Gas Emissions From New, Modified, and Reconstructed Fossil Fuel-Fired Electric Generating Units; Emission Guidelines for Greenhouse Gas Emissions From Existing Fossil Fuel-Fired Electric Generating Units; and Repeal of the Affordable Clean Energy Rule" (proposed rule), starting a comment period that ends on July 24, 88 Fed. Reg. 33,240 (May 23, 2023). The EPA's proposed rule relies heavily on hydrogen co-firing and carbon capture and sequestration (CCS) deployment as part of the decarbonization of the power-producing sector.