IPM Model – Revisions to Cost and Performance for APC Technologies

SDA FGD Cost Development Methodology

FINAL

August 2010 

Project 12301-007 

Perrin Quarles Associates, Inc. 

Prepared by

55 East Monroe Street • Chicago, IL 60603 USA • 312-269-2000 
 

LEGAL NOTICE 

This analysis ("Deliverable") was prepared by Sargent & Lundy, L.L.C. ("S&L"), expressly for the sole use 

of Perrin Quarles Associates, Inc. ("Client") in accordance with the agreement between S&L and Client. 

This Deliverable was prepared using the degree of skill and care ordinarily exercised by engineers 

practicing under similar circumstances. Client acknowledges: (1) S&L prepared this Deliverable subject to 

the particular scope limitations, budgetary and time constraints, and business objectives of the Client; (2) 

information and data provided by others may not have been independently verified by S&L; and (3) the 

information and data contained in this Deliverable are time sensitive and changes in the data, applicable 

codes, standards, and acceptable engineering practices may invalidate the findings of this Deliverable. Any 

use or reliance upon this Deliverable by third parties shall be at their sole risk. 

This work was funded and reviewed by the U.S. Environmental Protection Agency under the supervision of 

William A. Stevens, Senior Advisor – Power Technologies. Additional input and review was provided by 

Dr. Jim Staudt, President of Andover Technology Partners. 
IPM Model – Revisions to Cost and Performance for Project No. 12301-007

APC Technologies August 20, 2010

SDA FGD Cost Development Methodology – Final 

Page 1 

Establishment of Cost Basis 

Cost data for the SDA FGD systems was more limited than that for the wet FGD systems. A 

similar trend with generating capacity is generally seen between the wet and SDA system. The 

same generating capacity relationship was used for the wet and SDA cost estimation. 

A least squares curve fit of proprietary in-house cost data was defined as a "typical" SDA FGD 

retrofit for removal of 95% of the inlet sulfur. It should be noted that the lowest available SO2

emission guarantees, from the original equipment manufactures of SDA FGD systems, are 0.06 

lb/MMBtu. The typical SDA FGD retrofit was based on: 

• Retrofit Difficulty = 1 (Average retrofit difficulty); 

• Gross Heat Rate = 9800 Btu/kWh; 

• SO2 Rate = 2.0 lb/MMBtu; 

• Type of Coal = PRB; and 

• Project Execution = Multiple lump sum contracts; and 

• Recommended SO2 emission floor = 0.08 lb/MMBtu. 

Units below 50 MW will typically not install an SDA FGD system. Sulfur reductions for the 

small units would be accomplished by; treating smaller units at a single site with one SDA FGD 

system, switching to a lower sulfur coal, repowering with natural gas, dry sorbent injection, 

and/or a reduction in operating hours. Capital costs of approximately $800/kW may be used for 

units below 50 MW under the premise that these will be combined. 

Based on the typical SDA FGD performance, the technology should not be applied to fuels with 

more than 3 lb SO2/MMBtu and the cost estimator should be limited to fuels with less than 3 lb 

SO2/MMBtu. 

An alternate dry technology, circulating dry scrubber (CDS), can meet removals of 98% or 

greater over a large range of inlet sulfur concentrations. It should be noted that the lowest SO2

emission guarantees for a CDS FGD system are 0.04 lb/MMBtu. 

Methodology 

Inputs 

Several input variables are required in order to predict future retrofit costs. The gross unit size in 

MW (equivalent acfm) and sulfur content of the fuel are the major variables for the capital 

estimation. A retrofit factor that equates to difficulty in construction of the system must be 

defined. The costs herein could increase significantly for congested sites. The unit gross heat 

rate will factor into the amount of flue gas generated and ultimately the size of the absorber, 

reagent preparation, waste handling, and balance of plant costs. The SO2 rate will have the 

greatest influence on the reagent handling and waste handling facilities. The type of fuel 

(Bituminous, PRB, or Lignite) will influence the flue gas quantities as a result of the different 

typical heating values. 
IPM Model – Revisions to Cost and Performance for Project No. 12301-007

APC Technologies August 20, 2010

SDA FGD Cost Development Methodology – Final 

Page 2 

Outputs 

Total Project Costs (TPC) 

First the base installed costs are calculated for each required module (BM_). The base installed 

costs include: 

• All equipment; 

• Installation; 

• Buildings; 

• Foundations; 

• Electrical; and 

• Average retrofit difficulty. 

The modules are: 

BMR = Base absorber island cost 

BMF = Base reagent preparation and waste recycle/handling cost 

BMB = Base balance of plan costs including: ID or booster fans, piping, ductwork, electrical, etc. 

BM = BMR + BMF + BMB 

The total base installed cost (BM) is then increased by: 

• Engineering and construction management costs at 10% of the BM cost; 

• Labor adjustment for 6 x 10 hour shift premium, per diem, etc., at 10% of the BM 

cost; and 

• Contractor profit and fees at 10% of the BM cost. 

A capital, engineering, and construction cost subtotal (CECC) is established as the sum of the 

BM and the additional engineering and construction fees. 

Additional costs and financing expenditures for the project are computed based on the CECC. 

Financing and additional project costs include: 

• Owner's home office costs (owner's engineering, management, and procurement) at 

5% of the CECC; and 

• Allowance for Funds Used During Construction (AFUDC) at 10% of the CECC and 

owner's costs. The AFUDC is based on a three-year engineering and construction 

cycle. 
IPM Model – Revisions to Cost and Performance for Project No. 12301-007

APC Technologies August 20, 2010

SDA FGD Cost Development Methodology – Final 

Page 3 

The total project cost is based on a multiple lump sum contract approach. Should a turnkey 

engineering procurement construction (EPC) contract be executed, the total project cost could be 

10 to 15% higher than what is currently estimated. 

Escalation is not included in the estimate. The total project cost (TPC) is the sum of the CECC 

and the additional costs and financing expenditures. Table 1 contains an example capital cost 

estimation.
IPM Model – Revisions to Cost and Performance for Project No. 12301-007

APC Technologies August 20, 2010

SDA FGD Cost Development Methodology – Final 

Page 4 

Table 1. Example Capital Cost Estimate for the SDA FGD System (Costs are all based on 200
IPM Model – Revisions to Cost and Performance for Project No. 12301-007

APC Technologies August 20, 2010

SDA FGD Cost Development Methodology – Final 

Page 5 

Fixed O&M (FOM) 

The fixed operating and maintenance (O&M) cost is a function of the additional 

operations staff (FOMO), maintenance labor and materials (FOMM), and administrative 

labor (FOMA) associated with the SDA FGD installation. The FOM is the sum of the 

FOMO, FOMM, and FOMA. 

The following factors and assumptions underlie calculations of the FOM: 

• All of the FOM costs were tabulated on a per kilowatt-year (kW yr) basis. 

• In general, 8 additional operators are required for a SDA FGD system. The 

FOMO was based on the number of additional operations staff required. 

• The fixed maintenance materials and labor is a direct function of the process 

capital cost (BM). 

• The administrative labor is a function of the FOMO and FOMM. 

Variable O&M (VOM) 

Variable O&M is a function of: 

• Reagent use and unit costs; 

• Waste production and unit disposal costs; 

• Additional power required and unit power cost; and 

• Makeup water required and unit water cost. 

The following factors and assumptions underlie calculations of the VOM: 

• All of the VOM costs were tabulated on a per megawatt-hour (MWh) basis. 

• The reagent usage is a function of gross unit size, SO2 feed rate, and removal 

efficiency. The estimated reagent usage was based on a sulfur removal 

efficiency of 95% with a flue gas temperature into the SDA FGD of 300°F 

and an adiabatic approach to saturation of 30°F. The calcium-to-sulfur 

stoichiometric ratio varies based on inlet sulfur. The variation in 

stoichiometric ratio was accounted for in the estimation. The economic 

estimation is only valid up to 3 lb SO2/MMBtu inlet. The basis for the lime 

purity was 90% CaO with the balance being inert material. 
IPM Model – Revisions to Cost and Performance for Project No. 12301-007

APC Technologies August 20, 2010

SDA FGD Cost Development Methodology – Final 

Page 6 

• The waste generation rate is a function of inlet sulfur and calcium to sulfur 

stoichiometry. Both variables are accounted for in the waste generation 

estimation. The waste disposal rate is based on 10% moisture in the byproduct. 

• The additional power required includes increased fan power to account for the 

added SDA FGD pressure drop. This requirement is a function of gross unit 

size (actual gas flow rate) and sulfur rate. 

• The makeup water rate is a function of gross unit size (actual gas flow rate) 

and sulfur feed rate. 

Input options are provided for the user to adjust the variable O&M costs per unit. 

Average default values are included in the base estimate. The variable O&M costs per 

unit options are: 

• Limestone cost in $/ton; 

• Waste disposal costs in $/ton; 

• Auxiliary power cost in $/kWh; 

• Makeup water costs in $/1000 gallon; and 

• Operating labor rate (including all benefits) in $/hr. 

The variables that contribute to the overall VOM are: 

VOMR = Variable O&M costs for lime reagent 

VOMW = Variable O&M costs for waste disposal 

VOMP = Variable O&M costs for additional auxiliary power 

VOMM = Variable O&M costs for makeup water 

The total VOM is the sum of VOMR, VOMW, VOMP, and VOMM. Table 2 contains an 

example O&M cost estimate, while Table 3 is a complete capital and O&M cost estimate 

worksheet.
IPM Model – Revisions to Cost and Performance for Project No. 12301-007

APC Technologies August 20, 2010

SDA FGD Cost Development Methodology – Final 

Page 7 

Table 2. Example O&M Cost Estimate for the SDA FGD System (Costs are all based on 2009 
IPM Model – Revisions to Cost and Performance for Project No. 12301-007

APC Technologies August 20, 2010

SDA FGD Cost Development Methodology – Final 

Page 8 

Table 3. Example Complete Cost Estimate for the SDA FGD System (Costs are all based on 200
IPM Model – Revisions to Cost and Performance for Project No. 12301-007

APC Technologies August 20, 2010

SDA FGD Cost Development Methodology – Final 

Page 9