(ACE) Rule Overview Wyoming Department of Environmental Quality Air - - PowerPoint PPT Presentation

Affordable Clean Energy (ACE) Rule Overview

Wyoming Department of Environmental Quality – Air Quality Division May 27, 2020

ACE Rule Overview

 The ACE Rule replaces the Clean Power Plan (CPP):

 The CPP was promulgated in October 2015 and was

stayed by the U.S. Supreme Court in February 2016

 The ACE Rule was promulgated on July 8, 2019 and

became effective on September 8, 2019

 The ACE Rule sets Emissions Guidelines for states to

develop and submit state plans

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ACE Rule Overview

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• Basic overview of state plans:
• State plans will set Standards of Performance for

CO2 emissions from existing coal-fired electric generating units (EGUs)

• Emphasis upon state-specific, unit-specific

standards that consider varying operating conditions at each unit

• Revises implementation guidelines for Clean

Air Act Section 111(d)

Key Components of ACE Rule

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• Focus is on power plant efficiency-based

guidelines

• Standards are developed through rate-based

(lb/MWh)

• Standards are unit-specific
• Compliance requirements are unit-specific

and provide certain flexibilities

• Consider variabilities in operating conditions

Key Components of ACE Rule

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• States submit plan by July 8, 2022 (three

years from promulgation of ACE Rule)

• Plan considers:
• Unit-specific evaluations of candidate Best

System of Emission Reduction (BSER) Heat Rate Improvement (HRI) technologies and practices

• Monitoring, recordkeeping and reporting

requirements

• Future operating condition projections through

2035

BSER HRI Technologies

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• Candidate technologies for BSER HRI that

achieve emission reductions through efficiency gains:

• Neural Network/Intelligent Sootblowers
• Boiler Feed Pumps
• Air Heater and Duct Leakage Control
• Variable Frequency Drives
• Blade Path Upgrades for Steam Turbines
• Redesign or Replacement of Economizer
• Improved Operation and Maintenance (O&M)

Practices

Standards of Performance

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• There are five steps for establishing Standards
• f Performance under the ACE Rule:
• Establish baseline heat and emission rates
• BSER HRI technologies
• Evaluation of degradation rates for BSER HRI

technologies

• Evaluate “other factors”
• Develop a final Standard of Performance

Federally Enforceable Plan Requirements

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• Requirements for federally enforceable plan:
• Identification of Designated Facilities
• Setting Standards of Performance
• Identification of unit-specific recordkeeping,

reporting and monitoring requirements

• State reporting to EPA

Clean Air Act Section 111(d)

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• Clean Air Act Section 111(d):
• Establishes standards for existing sources that are

not regulated by National Ambient Air Quality Standards (NAAQS) or Clean Air Act Section 112.

• CO2 is one of these pollutants
• NAAQS pollutants (do not apply to this rule):

O3, PM2.5/PM10, NOx, SO2, CO, Pb

Revisions to CAA Section 111(d)

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• Revises:
• EPA’s role in providing information for states to

develop state plans

• Timing considerations for state plan submissions
• Timing considerations for EPA actions on state plans
• Timing considerations for EPA actions on federal

plans

• Changes to specific definitions to provide certainty

and clarity of intent

• Changes to completeness criteria for state plans
• Establishes process for determining completeness of

a state plan submission

Path Forward for ACE Rule

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• WDEQ-AQD must receive data from EGU
• perators on each unit:
• Necessary for measuring and setting baseline and

future heat and emission rates

• Necessary for choosing whether to calculate

through net vs. gross heat rate

• Demonstrates variability of operating conditions,

load demand, etc.

• WDEQ-AQD must receive public input on

performance standards and rule implementation

Options for Implementation

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• Option #1: State Plan
• Adoption of plan into Wyoming Air Quality

Standards and Regulations (WAQSR)

• Would have to go through statutory rulemaking

process to become state-effective rule

• Would have to go through state plan approval

process

• Would have to undergo EPA review and approval

process

• Potential timeframe for approval: 18-20 months

Options for Implementation

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• Option #2: Permit/Order/Consent Decree and Plan
• Develop and issue unit-specific, federally enforceable

permits

• Permits set performance standards for each unit
• Permits would undergo required public notice and legal

review

• Permits would be adopted into state plan
• Would have to undergo EPA review and approval process
• Potential timeframe for approval: 12-14 months

Options for Implementation

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• Option #3: Federal Plan
• EPA develops federally enforceable plan for existing

coal-fired EGUs in Wyoming

• AQD, facilities would undertake early engagement with

EPA

• Plan would undergo federal public comment and

approval process

• EPA would maintain primacy over plan
• Potential timeframe for approval: Uncertain

Options for Implementation

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• Option #4: Other Options
• We are interested to hear and consider any other ideas or

possibilities for rule implementation that you may have.

• We will open the floor for discussion during the public

input session following questions about this presentation.

ACE Rule Resources

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• Wyoming DEQ Website: ACE Rule
• You can access the DEQ-AQD ACE Rule webpage at:

deq.wyoming.gov/aqd/resources/ace-rule/

• Users can access a number of different ACE Rule

resources including: this PowerPoint presentation, EPA ACE Rule fact sheets, various implementation guidance documents, etc.

• This webpage will be updated with more information as

the implementation process moves forward

Providing Written Comment

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• The AQD will accept written input through June

10; input must be submitted in one of the following manners:

• Electronically by filling out the electronic comment form at

http://aq.wyomingdeq.commentinput.com/

• Via mail addressed to Nancy Vehr, Administrator, DEQ/AQD,

200 West 17th Street, Cheyenne, Wyoming, 82002, or faxed to 307-365-1784

Questions?

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• Please feel free to ask any questions at this time

about this presentation or other aspects of the ACE Rule