GHG BACT Developments
Justin Fickas
Clay Raasch
˃ Since January 2011, Greenhouse Gases (GHGs)
have been evaluated under Prevention of
Significant Deterioration (PSD) permitting
˃ The GHG BACT process can prove challenging
Learning curve for both permitting authorities and
˃ What are the current trends regarding GHG
Phase II Report on BACT for GHGs
˃ Work Group Phase II report - dated August 5, 2010 (made
public October 5, 2010)
˃ Report details considerations for conducting five step “top
down” BACT analysis and how to incorporate efficiency into
this process
Energy Efficient Processes and Technologies (EEPT)
Considerations for possible level of analysis
Define part of facility subject to BACT review
Describe equipment/operations for which BACT limit or work
practice standard must be developed
– Equipment-level, production-level, and facility-level
˃ Recommendations about how Innovative Control Technology
(ICT) waiver can be used to encourage innovative
˃ Many of these concepts incorporated into the EPA PSD and
Title V Permitting Guidance for Greenhouse Gases (March
Pre-Step 1: Defining the “Source”
˃ Applicant defines the goals, objectives, purpose, or
basic design for the proposed source/modification
˃ BACT process does not typically redefine these basic
design elements
˃ When fuel efficiency or overall production process
efficiency are considered as an available control option,
defining the source/project is a critical step in the BACT
Pre-Step 1: Defining the “Source”
March 15th, 2012 Letter from EPA Region 5 to the Wisconsin
Department of Natural Resources (WDNR)
˃ Letter was in reference to a draft PSD permit for the Milwaukee
Metropolitan Sewerage District Jones Island Water Reclamation
Permit involved installation of five new simple cycle combustion turbines
Operate on landfill gas with natural gas as a backup
Draft permit comments stated that Step 1 of the GHG BACT did not
consider either combined cycle turbines or combined heat and
power (CHP) systems
Comments included request that GHG BACT be revised to consider these items
in Step 1 of the BACT
Redefining the source?
˃ WDNR Response – Final Permit Issued May 25, 2012
Combined Cycle not Appropriate for the Site (Footprint Issues)
Simple Cycle Similar to CHP
Step 1: Identify Available Controls
Resources are still limited for identifying available criteria pollutant
control options applicable to GHGs
EPA’s RBLC database includes limited GHG information
 Limited determinations of BACT by regulatory agencies for other similar
 Air pollution control equipment vendors have not previously targeted
GHG emissions reductions in the absence of any regulatory driver
Assuming no add-on controls for GHGs will be available for most
emission units, the only available control option will be “loweremitting process” type GHG control options
˃ Primary GHG control options identified by the Work Group or EPA to
date are fuel selection, energy efficiency, and CCS – “redefinition of
the source possible”
˃ What controls are available for non-CO2 GHGs?
Step 1: Identify Available Controls
˃ Identify available EEPTs
Review unit’s energy performance with
“benchmark” technology in use, mitigation
options for specific industry sectors, and
new available EEPTs potentially built outside
of US
Sets of efficiency measures may be
considered as available technology
For modifications to existing units, consider
extent of modification, when identifying
potential efficiency gains
Step 2: Eliminate Technically
Infeasible Controls (1/2)
˃ Work Group and current guidance endorse the long standing
EPA policy for Step 2 presented in the 1990 Draft NSR Manual
˃ Evaluations of technical feasibility should consider various
aspects of the control option including:
Development stage (licensing and commercial sales vs. only R&D
or pilot scale)
Scope of installations (i.e., how many similar sources have
implemented this control option?) – feasible if operated on the
same type of source
Physical or chemical properties of the emissions stream in
comparison to emissions streams from similar sources
successfully implementing the control option
Step 2: Eliminate Technically
Infeasible Controls (2/2)
˃ No obvious technical limitations to fuel selection
and energy efficiency for new sources
˃ Elimination of EEPTs may be based on concerns
about reliability/operational characteristics of a
˃ GHG Specific Considerations – Availability of
Lack of a commercial guarantee, by itself, is not sufficient
grounds to determine technical infeasibility
˃ CCS may not be technically feasible in certain cases
Low purity CO2 streams
Low CO2 emission amounts
Step 3: Rank Remaining Control
No significant consolidated database of GHG emissions performance
of many industrial source types as there is for criteria pollutants
˃ Typical metrics for comparing available control options for criteria
pollutants may not apply to certain GHG controls or may be very
difficult to explicitly quantify
˃ For common fossil-fuel fired combustion units, like boilers and
engines, GHG emissions performance on a mass pollutant emitted
per energy output basis is the most likely basis for comparison (i.e.,
lb/MW steam or lb/hp-hr engine output)
˃ If energy efficiency is selected as the top control option, what level
of energy consumption per unit output constitutes BACT for new and
existing sources?
Step 4: “Top Down” Evaluation of Controls
Start with highest ranked control option from Step 3 and evaluate
potential for adverse energy, environmental, and economic impacts.
If no adverse impacts, select BACT based on application of
remaining control option.
˃ Energy Impacts: Consider energy consumption of GHG control
Environmental Impacts: Consider water, waste, air toxics, and
criteria pollutant impacts from GHG controls options
Parasitic load from a potential GHG control option is too high based on
limited emission reduction
Collateral criteria pollutant increases from GHG control options cannot
jeopardize compliance with criteria pollutant BACT limits, NAAQS, or
Economic Impacts: Costs should be expressed on a CO2e basis,
but no clear threshold has been established – CCS should be
Step 5: Select BACT (1/2)
˃ Output-based limits (e.g., lb CO2/MWh, lb CO2/lb steam,
lb CO2/hp-hr, etc.) are generally preferred over fuelinput based standards tied to fuel carbon content
˃ Analysis should confirm/deny suitability of EEPT or set of
EEPTs selected as BACT
˃ BACT selection should take into effect changing loads or
energy efficiency and compliance with the BACT limits
˃ Energy efficiency may vary with time due to degradation
of equipment or because of operational issues
Step 5: Select BACT (2/2)
˃ No NAAQS for GHGs, so GHG BACT limits should be
expressed on an annual average basis (i.e., 12month calendar year or 365-day rolling average
˃ If output-based GHG emissions increase during
startup and shutdown, secondary lb/event BACT
limits may be necessary
˃ Compliance demonstration methodologies for units
with existing CEMs may be straightforward by adding
GHG analyzers to existing system
˃ For emission units without CEMs, periodic stack
testing may be required in conjunction with fuel
usage or output tracking
Recent EPA GHG BACT Actions (1 of 2)
˃ Palmdale Hybrid Energy Center, Antelope Valley, CA
(Region 9)
Hybrid Power Project – CCT Component
12-month rolling average CO2e tpy limit sitewide
365-day rolling average source limit (lb CO2/MWh) net
˃ Lower Colorado River Authority – Ferguson,
Horseshoe Bend, TX (Region 6)
CCT Project
TPY limits (365-day rolling average) for CO2, CH4, and N2O
established for each combustion turbine
Ton CO2/MWh (net) limit for each combustion turbine
Recent EPA GHG BACT Actions (2 of 2)
˃ Pioneer Valley Energy Center (Region 1)
Combine Cycle Combustion Turbine Project
BACT CO2e Limit – 895 lbs of CO2e/MWhgrid 365 day rolling
Initial source test for CO2, and use emission factors from
40 CFR Part 98 for other GHGs
Permit Condition - If source test does not meet the design
emissions limit, then the owner/operator shall remedy the
CCT’s failure to meet the design emissions limit, and shall
not combust any fuel in the CCT until the owner/operator
demonstrates compliance with the emissions limit during a
subsequent test
Justin Fickas
53 Perimeter Center East
Suite 230
Atlanta, GA 30346
Office: (678) 441-9977
Cell: (678) 549-9755
Fax: (678) 441-9978
[email protected]

GHG BACT Developments (09 11 12 JF)