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New York State Department of Environmental Conservation 

Best Available Retrofit Technology Determination 

Facility Oswego Harbor Power 

Location Oswego, NY 

Oswego County 

Permit ID 7-3512-00030 

Source Category Fossil-fuel fired steam electric plant of 

more than 250 mmBtu/hr heat input 

I. Introduction 

The above referenced facility contains at least one emission source that falls under the 

requirements of the federal Best Available Retrofit Technology (BART) rule under 40 CFR Part 

51 and Appendix Y, and the New York State BART regulation as codified under 6 NYCRR Part 

249. These requirements affect an emission source which fulfills the following criteria: 

1. Falls within one of 26 specific source categories, 

2. Was not in operation prior to August 7, 1962 and was in existence on August 7, 1977, or 

underwent reconstruction between August 7, 1962 and August 7, 1977, and 

3. Has a potential to emit (collectively, with other emission sources at the facility which 

fulfill items 1 and 2) of 250 tons per year or more of any visibility-impairing pollutant. 

In accordance with BART requirements, each BART-eligible facility performed a BART 

analysis of controls for sulfur dioxide, nitrogen oxides and particulate matter. This analysis took 

into account such factors as the cost of controls, energy and non-air quality environmental 

impacts of compliance, any existing pollution control technology in use at the source, the 

remaining useful life of the source, and the degree of improvement in visibility which may 

reasonably be anticipated to result from the use of such technology. 

This document summarizes the reasoning behind the Department’s BART determination, 

including the level of controls and emission limits that constitute BART for this facility’s eligible 

emission source(s). Each analysis and BART determination was submitted to the Federal Land 

Managers (FLMs) for their review in accordance with Regional Haze State Implementation Plan 

(SIP) requirements. Comments received from the FLMs on this determination will be included 

with its official submission to the U.S. Environmental Protection Agency (EPA). 

The Department has modified this facility’s Title V permit to include the enforceable BART 

limits. The modifications were noticed in New York State’s Environmental Notice Bulletin on 

February 15, 2012. Upon completion of this public notice period, the modified permit was 

submitted to EPA for review on April 4, 2012. The final modified permit was issued on May 16, 

2012. This permit is now being submitted to EPA as a revision to the New York Regional Haze 

SIP. 

 
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II. BART Analysis Summary 

NRG submitted a BART analysis for the Oswego Harbor Power facility dated August 4, 2010, 

with an associated engineering evaluation for NOx dated July 26, 2010. The following emission 

sources had previously been identified as BART-eligible and were therefore included in the 

analysis: 

Boiler No. 5 – Emission Unit U-00005; Emission Source S0005 

• This unit is a Foster Wheeler wall-fired boiler with a maximum heat input of 8,033 

mmBtu/hr. This unit is capable of burning natural gas or 1.5 percent sulfur fuel oil. 

Operation commenced in 1975. 

Boiler No. 6 – Emission Unit U-00006; Emission Source S0006 

• This unit is a Foster Wheeler wall-fired boiler with a maximum heat input of 8,088 

mmBtu/hr. This unit is capable of burning natural gas or 0.75 percent sulfur fuel oil. 

Operation commenced in 1980. 

Each of these units is equipped with low NOx burners, including LN-REACH, overfire 

air (OFA) and flue gas recirculation (FGR) control for NOx emissions. Each unit has an 

electrostatic precipitator (ESP) for PM control. Both are considered to essentially be 

“peaking” units, with actual capacity being much lower than rated capacity. Each unit 

has had a capacity factor of 3.2 percent or less during the baseline period (2007 – 2009), 

and neither has had a capacity factor above 10 percent since 2001. These operational 

characteristics were taken into account in this BART analysis as allowed by EPA 

guidance (70 FR 39167). 

A summary of the analysis’ findings for each pollutant are as follows: 

Boiler No. 5 

• SO2

Oswego Unit 5 currently burns oil with a fuel sulfur limit of 1.5 percent by weight. An 

economic analysis indicated that switching to a lower fuel is economically feasible. In 

order to meet the presumptive limit for oil-fired boilers set by EPA in its BART rule, 

NRG proposes to revise its permit limit to burn oil with a sulfur content of 0.75 percent 

by weight. 

Additionally, in anticipation of the Department’s plans to revise its fuel sulfur 

requirements (and citing fuel handling advantages of a single oil on-site), NRG is 

committing to purchasing no oil in the future with a sulfur content greater than 0.5 

percent for Units 5 and 6. 

• NOx
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During the baseline period of 2007 to 2009, the annual capacity factor for Unit 5 ranged 

from 0.52 percent (2009) to 2.68 percent (2007). The highest 12-month rolling average 

capacity factor during this period for either unit was 3.2 percent (Unit 5); this value was 

used as the basis in calculating the baseline and projected annual emissions for both units. 

The baseline for NOx emissions from Unit 5 was found to be 243 tons per year (tpy). The 

average controlled NOx emission rate was 0.22 lb/mmBtu over this period. 

The following table presents a list of the potential NOx control technology options for 

Units 5 and 6. 

Potential NOx Control Technologies

Combustion Controls

  

Low NOx Burners (LNB), Overfire Air (OFA),  

and Flue Gas Recirculation (FGR)  

(optimize existing NOx combustion controls)

   Low NOx Reduced Emissions and Advanced Combustion  

Hardware (LN‐REACH) and modified OFA controls

   Neutral Network Combustion Control Systems

   Gas Reburn Systems and Advanced Gas Reburn

   Fuel Lean Gas Reburn (FLGR) and Amine‐Enhanced FLGR

Post‐Combustion Controls

   Selective Non‐Catalytic Reduction (SNCR)

   Selective Catalytic Reduction (SCR)

Innovative Control Technologies

   Rotating Overfire Air (ROFA)

   ROFA plus SNCR (Rotamix)

   NOxStar Control System

   Powerspan ECO Technology

NRG’s BART plan describes the technical feasibility of each of these control options for 

Unit 5. The technically feasible control options are listed in the table below, in order of 

descending control effectiveness. This table outlines the emissions that would remain 

after the application of the control technology, and the average cost-effectiveness 

resulting from that level of emission reductions. (As previously stated, the cost figures 

and annual emission estimates for each control option were calculated according to a 3.2 

percent capacity factor based on historical annual hours of operation.) 

 
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Control Technology

Controlled

Annual

Emissions (tpy)

Annual Emission

Reductions (tpy)

Average Cost

Effectiveness

($/ton)

SCR 33.0 209.1 $73,113

LN‐REACH (steam atomizer) +

modified OFA and FLGR 132.1 110.0 $37,421

LN‐REACH (steam atomizer) +

modified OFA + SNCR 143.1 99.0 $22,194

LN‐REACH (pressure atomizer) +

modified OFA and FLGR 143.1 99.0 $36,401

LN‐REACH (pressure atomizer) +

modified OFA + SNCR 154.1 88.0 $19,141

LN‐REACH (steam atomizer) +

modified OFA 187.1 55.0 $16,873

LN‐REACH (pressure atomizer) +

modified OFA 198.1 44.0 $8,748

Optimize LNB/OFA/FGR with

Neural Network Control System 231.1 11.0 $42,809

Baseline LNB/OFA/FGR 242.1  ‐‐  ‐‐ 

NRG notes that these cost-effectiveness values exceed the $5,500 per ton figure 

established by the Department for BART. NRG states that, assuming actual capacity 

remains at low levels, no additional controls are economically feasible for BART. 

NRG requests that the existing low NOx burners, LN-REACH, OFA, and FGR be 

accepted as BART for Unit 5. NRG proposes to accept a NOx emission limit based on 

the NOx emissions level that would prevent the cheapest control option from being costeffective (i.e., become lower than the $5,500 per ton threshold). For Unit 5, the cheapest 

control option was to optimize combustion with burner changes and modify the OFA 

configuration ($8,748 per ton). NRG back-calculated the threshold emission level that 

would prevent this option from being cost-effective: 405 tons per year, based on the 3.2 

percent capacity factor used in the analysis. In its NOx RACT analysis submitted under 

separate cover on December 29, 2011, NRG used updated emissions data to revise this 

proposed emissions threshold to 383 tons per year. 

• PM 

Unit 5 presently operates with an ESP for particulate control. The most recent PM stack 

tests measured a total PM rate of 0.0304 lb/mmBtu and a filterable PM rate of 0.0217 

lb/mmBtu. Because of the current level of control, additional controls proved to be 

economically infeasible. A cost analysis for a fabric filter unit indicated costs of 

approximately $40,600 per ton of PM at actual emission rates. ESP conditioning was 
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also prohibitively expensive, at around $37,000 per ton. NRG also submitted an analysis 

for adding additional collection fields to the existing ESP, which also proved to be well 

above a reasonable cost-effectiveness, at around $60,000 per ton. 

NRG back-calculated the PM emission levels that would be required to make these 

controls cost-effective, which proved to be much higher than the levels seen under actual 

operation. NRG also notes a number of ESP improvements that have been undertaken 

recently. It is recommended that the current operation of the ESP constitutes BART for 

PM. 

Boiler No. 6 

• SO2

Unit 6 currently has a permit limit for 0.75 percent sulfur oil, which is less than the 

presumptive limit established in the EPA BART rule of 1.0 percent or less for oil-fired 

utility boilers. NRG therefore requests that the fuel currently being burned be accepted 

as BART. 

In anticipation of the Department’s plans to revise its fuel sulfur requirements (and citing 

fuel handling advantages of a single oil on-site), NRG is also committing to purchasing 

no oil in the future with a sulfur content greater than 0.5 percent for Units 5 and 6. 

• NOx

Baseline emissions for Unit 6, based on actual emissions during the baseline years of 

2007 to 2009, were found to be 107 tpy. The average controlled NOx emission rate was 

0.19 lb/mmBtu over this period. 

Potential NOx control options are the same as those provided under the Unit 5 section. 

NRG’s BART plan describes the technical feasibility of each of these control options for 

Unit 6. The technically feasible control options are listed in the table below, in order of 

descending control effectiveness. This table outlines the emissions that would remain 

after the application of the control technology, and the average cost-effectiveness 

resulting from that level of emission reductions. (Again, the cost figures and annual 

emission estimates for each control option were calculated according to a 3.2 percent 

capacity factor based on historical annual hours of operation.) 

 
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Control Technology

Controlled

Annual

Emissions (tpy)

Annual Emission

Reductions (tpy)

Average Cost

Effectiveness

($/ton)

SCR 33.2 176.9 $86,422

LN‐REACH (steam atomizer) +

modified OFA and FLGR 132.7 77.4 $53,182

LN‐REACH (steam atomizer) +

modified OFA + SNCR 143.8 66.3 $33,140

LN‐REACH (pressure atomizer) +

modified OFA and FLGR 143.8 66.3 $54,354

LN‐REACH (pressure atomizer) +

modified OFA + SNCR 154.8 55.3 $30,459

LN‐REACH (steam atomizer) +

modified OFA 177.0 33.1 $27,205

LN‐REACH (pressure atomizer) +

modified OFA 188.0 22.1 $17,416

Optimize LNB/OFA/FGR with

Neural Network Control System 199.1 11.0 $42,809

Baseline LNB/OFA/FGR 210.1  ‐‐  ‐‐ 

NRG notes that these cost-effectiveness values exceed the $5,500 per ton threshold 

established by the Department for BART. NRG states that, assuming actual capacity 

remains at low levels, no additional controls are economically feasible for BART. 

NRG requests that the existing low NOx burners, LN-REACH, OFA, and FGR be 

accepted as BART for Unit 6. NRG proposes to accept a NOx emission limit based on 

the emissions level that would prevent the cheapest control option from being costeffective (i.e., become lower than the $5,500/ton threshold). For Unit 6, the cheapest 

control option was to optimize combustion with burner changes and modify the OFA 

configuration ($17,416/ton). NRG back-calculated the threshold emission level that 

would prevent this option from being cost-effective: 796 tons per year, based on the 3.2 

percent capacity factor used in the analysis. In its NOx RACT analysis submitted under 

separate cover on December 29, 2011, NRG used updated emissions data to revise this 

proposed emissions threshold to 665 tons per year. 

• PM 

Unit 6 presently operates with an ESP for particulate control. The most recent PM stack 

tests measured a total PM rate of 0.0296 lb/mmBtu and a filterable PM rate of 0.0218 

lb/mmBtu. Because of the current level of control, additional controls proved to be 

economically infeasible. A cost analysis for a fabric filter unit indicated costs of 

approximately $57,300 per ton of PM at actual emission rates. ESP conditioning was 
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also prohibitively expensive, at around $48,800 per ton. NRG also submitted an analysis 

for adding additional collection fields to the existing ESP, which also proved to be well 

above a reasonable cost-effectiveness, at around $89,000 per ton. 

NRG back-calculated the PM emission levels that would be required to make these 

controls cost-effective, which proved to be much higher than the levels seen under actual 

operation. NRG also notes a number of ESP improvements that have been undertaken 

recently. It is recommended that the current operation of the ESP constitutes BART for 

PM. 

III. BART Determination 

The Department finds that the following shall constitute BART for the Oswego Harbor Power 

emission sources: 

Boilers No. 5 and 6 

• SO2

The Department accepts NRG’s commitment to lower the permitted No. 6 fuel sulfur 

limit from 1.5 percent to 0.75 percent by weight for Unit 5. The Department also accepts 

NRG’s proposal to retain the existing 0.75 percent limit for Unit 6. 

It should be noted that the Department is pursuing a regulatory revision to 6 NYCRR Part 

225-1 to lower the acceptable fuel sulfur limit to 0.5 percent statewide (not including the 

New York City and lower Hudson Valley areas, which are already subject to more 

stringent limits). This revision is tentatively scheduled to be effective for 2014. The 

Department indicated to facility owners that the revisions may supersede BART limits 

such as those proposed by NRG for Units 5 and 6. NRG has committed to future 

purchases of oil with a sulfur content no higher than 0.5 percent for Units 5 and 6. 

• NOx

The Department accepts NRG’s finding that no additional controls are necessary to 

satisfy BART for NOx for Units 5 and 6. All available control options were adequately 

demonstrated to be technically or economically infeasible. 

NRG has proposed, and the Department is accepting, emission limits of 383 tons per year 

and 665 tons per year for Units 5 and 6, respectively. NRG proposed these revised limits 

in its NOx RACT plan, submitted to the Department December 29, 2011. (These limits 

were slightly more stringent than those proposed in the August 4, 2010 BART analysis.) 

 
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• PM 

The Department accepts the current use of an ESP as BART for PM. NRG demonstrated 

that alternate controls and ESP upgrades were economically infeasible. Particulate limits 

of 0.1 lb/mmBtu will be retained for Units 5 and 6.