EPA Section 111 Rules
Prerequisites
CAA Section 111(d) authorizes EPA to set performance standards for existing stationary sources of air pollution. For CO2, this means existing power plants. The section has become the legal battleground for US power sector climate policy, producing three different rules across three administrations, with the Supreme Court reshaping EPA's authority each time.
The Clean Power Plan (2015, Obama). Set state-level CO2 targets and allowed compliance through generation shifting: replacing coal with gas and renewables. It effectively mandated a change in the electricity mix, not just plant-level efficiency. The Supreme Court stayed it before implementation.
The ACE Rule (2019, Trump). Limited compliance to heat-rate improvements at individual coal plants: roughly 1-2% efficiency gains. Environmental groups called it meaningless. Courts vacated it as insufficiently justified.
The Section 111 Rule (2024, Biden). Required existing coal plants operating past 2039 and new gas plants to achieve 90% carbon capture by 2032. This was plant-level performance (satisfying the Supreme Court's constraints) but at a stringency that effectively required CCS or closure.
Why does Section 111(d) keep producing rules that get struck down or vacated?
Because the statute was not designed for CO2. Section 111(d) was written for conventional pollutants at individual sources. Applying it to CO2 requires either stretching the statute (generation shifting, struck down) or setting stringency levels that assume unproven technology (CCS at 90%, legally vulnerable). Each administration pushes the legal boundaries differently, and each push gets tested in court.
The Clean Power Plan was stayed by the Supreme Court before implementation because:
The Clean Power Plan's fatal legal flaw was its mechanism: it told states to change their generation mix, not just improve individual plants. The Supreme Court determined that this system-wide restructuring was a "major question" requiring explicit Congressional authorization that the CAA does not provide.
The answer is DLesson complete
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