Tetra Tech, Inc.

10306 Eaton Place, Suite 340

Fairfax, VA 22030

phone 703-385-6000

fax 703-385-6007

TO: Paul Shriner and Jan Matuszko, EPA

FROM: John Sunda (SAIC) and Kelly Meadows

DATE: April 22, 2010

SUBJECT: Comparison of Cooling Tower Retrofit Costs to the Cost of New 

Repowered Power Plants

EPA requested that Tt and SAIC compare the cost of retrofitting a facility

cycle cooling to the cost of constructing a new power plant and to the cost to 

plant. This memo describes the results of the research.

Capital Costs for a New Plant

Table 1 presents a comparison of the 

tower at an existing power plant 

with the same generating capacity. 

for both the existing and new plant. 

Cooling tower retrofit costs are based on cost factors derived for EPA 316(b) compliance 

costs, which are based on the factors used 

Costs for “average” difficulty and “difficult” retrofits are presented

will vary depending on existing plant site conditions. These cost factors 

flow rates as the basis, which have been estimated 

and typical heat rates of 9,300 BTU/Kwh (plant efficiency = 37%) for 

plant and 10,200 BTU/Kwh (plant efficiency = 33%) for 

The new plant construction capital costs are based on cost assumptions used by EIA in 

developing economic data in their 

costs and do not include escalation or financing costs

estimates for construction costs of new nuclear power plants have increased in recent 

MEMORANDUM

10306 Eaton Place, Suite 340

Paul Shriner and Jan Matuszko, EPA

John Sunda (SAIC) and Kelly Meadows

, 2010

Comparison of Cooling Tower Retrofit Costs to the Cost of New 

Power Plants

that Tt and SAIC compare the cost of retrofitting a facility with

cycle cooling to the cost of constructing a new power plant and to the cost to 

plant. This memo describes the results of the research.

Costs for a New Plant

Table 1 presents a comparison of the capital costs of retrofitting a recirculating cooling 

an existing power plant to the costs of building a new greenfield power plant 

with the same generating capacity. A plant capacity of 1,000 MW was chosen as the size 

for both the existing and new plant. 

Cooling tower retrofit costs are based on cost factors derived for EPA 316(b) compliance 

sed on the factors used in the EPRI Tower Calculation Worksheet. 

for “average” difficulty and “difficult” retrofits are presented, since the actual costs 

will vary depending on existing plant site conditions. These cost factors use 

which have been estimated assuming a condenser delta T of 15

rates of 9,300 BTU/Kwh (plant efficiency = 37%) for an existing coal 

plant and 10,200 BTU/Kwh (plant efficiency = 33%) for an existing nuclear plant.

ew plant construction capital costs are based on cost assumptions used by EIA in 

developing economic data in their Annual Energy Outlook 2009. These are overnight 

escalation or financing costs. Other sources suggest

mates for construction costs of new nuclear power plants have increased in recent 

Comparison of Cooling Tower Retrofit Costs to the Cost of New and 

with closedcycle cooling to the cost of constructing a new power plant and to the cost to repower a 

costs of retrofitting a recirculating cooling 

eenfield power plant 

A plant capacity of 1,000 MW was chosen as the size 

Cooling tower retrofit costs are based on cost factors derived for EPA 316(b) compliance 

EPRI Tower Calculation Worksheet. 

since the actual costs 

use condenser 

elta T of 15oF 

existing coal 

existing nuclear plant.

ew plant construction capital costs are based on cost assumptions used by EIA in 

These are overnight 

suggest that the 

mates for construction costs of new nuclear power plants have increased in recent 
years and are very uncertain, with costs possibly being greater than those used by EIA. A 

2008 report stated that companies that were planning new nuclear units indicated that the 

total costs (including escalation and financing costs) would be in the range of $5,500/kW 

to $8,100/kW (Synapse 2008a). To capture these higher costs, the “advanced nuclear –

high” costs were added to Table 1 to reflect these higher estimates using the upper end of 

the range of costs that Florida Power & Light (FPL) projected in October 2007 for two 

new plants (Synapse 2008). Interest and escalation may add between 35% and 75% to 

the costs.

Other sources indicate that the estimated costs of new coal plants have been increasing 

recently as well. A 2008 report states that the estimated costs of building new coal plants

has reached $3,500 per kW, not including financing costs (Synapse 2008b). These cost 

increases are mostly due to a significant increase in the worldwide demand for power

plant design and construction resources, commodities, and equipment. This report was 

written in mid 2008, a time when commodity prices had increased rapidly and reached a 

peak and have subsequently dropped to lower levels due to the recent worldwide 

economic downturn. However, high construction costs remain as a concern Table 2

provides some recent examples of capital cost estimates for both nuclear and coal-fired 

plants. Two of the coal plants were cancelled in late 2008 and 2009 due to concerns 

about increased costs and greenhouse gas emissions. Table 2 also shows that the 

estimated cost of the cooling tower and basin component are a small portion (≤2%) of 

total costs. This is based on the assumption that cooling tower and basin costs are 

roughly $80/gpm (SAIC 2010).

In summary (as shown in Table 1), costs for construction of a conventional fossil fuel 

plant can be nearly 14 times higher than the cost to retrofit a closed-cycle cooling system 

at a comparable facility. Costs for a new combined cycle plant can be nearly 7 times 

higher, while the costs for a new nuclear facility can be as much as 20 times higher.

Capital Costs for a Repowered Plant

While the costs in Table 1 reflect greenfield costs for a new plant, they can be viewed as 

indicative of the magnitude of costs for a full repowering at coal and combined cycle 

power plants as well.1 The generating capacities of new repowered plants will in most

cases be greater than those of the existing plants. In the case of repowering of an existing 

steam plant to combined cycle, the repowered capacity could be as much as 200% greater 

than the existing plant, while producing the same amount of waste heat and requiring the 

same amount of cooling water as before.

On a non-incremental dollar/MW basis, fossil-fuel repowering projects can typically be 

implemented for about 70-80% of the cost of a greenfield plant in dollars/MW, because 

 

1

It is a common misconception that repowered plants cost more than greenfield plants, but this is only true 

if cost differences are based on the incremental changes in MW capacity (i.e., if the dollars/MW estimate is 

based on the difference in MW between the existing and repowered units).
they are able to utilize existing infrastructure and steam turbines (ALSTOM Power Inc. 

2003).2

Other Cost Considerations

There are many other cost considerations, in addition to differences in capital costs, that 

factor into the decision to construct new generating units either onsite or at a new 

location. The decision to construct new generating units requires a detailed economic 

evaluation of all of these factors. These cost factors include:

 Plant efficiency and energy penalty - New power generating units can be designed 

to operate more efficiently than existing units that are retrofitted. Thus, new 

generating units will use less fuel and cost less to operate. This increased 

efficiency results from the use of state-of-the-art power generation and cooling 

technology that is more efficient and designed for optimized performance. While 

the use of a recirculating cooling tower with the new unit may still experience 

some amount of both parasitic energy requirements and turbine efficiency

reductions compared to a once-through system, there is a greater opportunity to 

design the system to optimize system performance plus in most cases the 

increased generating unit efficiency will be much greater than the energy penalty.

 Changes in plant dispatch schedule and capacity utilization - A more cost efficient 

plant will tend to be dispatched more frequently resulting in a higher utilization 

rate affecting long term revenue estimates.

 Fuel type – Changes in fuel type can also affect operating costs, dispatch rate, 

pollution emissions, and potential costs associated with carbon emissions.

 Permitting – Existing generating units may require only minor modification to 

existing permits. New units may undergo an extensive, lengthy, and potentially 

restrictive permitting process.

 Downtime costs – Offsite new generating units will have no downtime costs. 

Onsite new generating units will result in minimal downtime, if any, depending 

on the need to tie into existing infrastructure such as water intakes or power 

distribution.

 Timeframe – Cooling tower retrofits can be accomplished within a period of 

several years. New generating units require a long lead time of several years to 

plan plus up to seven years to obtain required permits.

 Service life – New generating units will tend to have a much longer service life 

than retrofitted existing generating units. O&M costs of generating units tend to 

increase over time. 

 New generating unit tower costs – New units with recirculating cooling towers 

will completely avoid retrofit costs and may have lower capital costs than new 

units with once-through cooling systems. See SAIC memo: “Estimation of Net 

Difference in Capital and O&M Costs for Once-through Versus Closed Cycle 

 

2 The downside is that the repowered plant usually will be less efficient than a comparable greenfield plant. 

In many cases, the repowering option may produce a more favorable long-term financial return than the 

greenfield alternative because the lower capital costs make up for the higher fuel cost associated with the 

lower efficiency. The development of repowering costs and the financial tradeoffs involved will vary from 

site to site and are beyond the scope of this analysis.
Cooling for New Generating Units at Existing Power Plants and for Repowering 

of Existing Generating Units” March 5, 2010.

 Flue gas disposal - New and repowered units requiring air pollution equipment 

upgrades where natural draft cooling towers (NDCT) are an available option can 

save costs of a new stack by disposing of flue gas through the NDCT. See SAIC 

memo: “Technology Analysis for the Discharge of Power Plant Combustion Flue 

Gas Through Natural Draft Cooling Towers.” March 12, 2010.

 Future environmental requirements and regulations – Uncertainty about future 

regulation and associated costs regarding emission of carbon dioxide is clouding 

the current decision making process. Once these regulations are enacted, the 

associated costs and credits will factor in as well. 

References

ALSTOM Power Inc. Schretter, J. Williams, S. Brandett, J. Repowering: A Financially 

Compelling Method to Improve Existing Assets. Winter 2003.

http://beaconenergy.com/html/JSPF%20Repower%20Winter03%20article.pdf

EIA. Assumptions to the Annual Energy Outlook 2009. Table 8-2 Costs and Performance 

Characteristics of New Central station Electricity Generation technologies. 2009.

Synapse Energy Economics Inc. David Schlissel and Bruce Biewald. Nuclear Power 

Plant - Construction Costs. July 2008a.

Synapse Energy Economics Inc. David Schlissel, Allison Smith and Rachel Wilson. 

Coal-Fired Power Plant - Construction Costs. July 2008b.

AMP. News Release “AMP ANNOUNCES LIKELY CONVERSION OF AMPGS 

PROJECT” November 25, 2009.

http://media.cleveland.com/business_impact/other/Project%20conversion%20release.pdf

Journal Sentinel. Milwaukee Wisconsin. PSC rejects Alliant Energy's proposed coal 

plant. Nov. 11, 2008

http://www.jsonline.com/business/34277094.html

Miami Herald “FPL suspends long-term projects, hints at job cuts” January 15, 2010.

http://www.miamiherald.com/2010/01/14/1426344/fpl-suspends-long-term-projects.html 

Charlotte Business Journal. “Cost of Duke Energy's Cliffside project holding steady”

March 19, 2010.
iStockAnalyst. “Federal loan guarantees encourages Levy County, Fla., plant 

construction” February 18, 2010.

http://www.istockanalyst.com/article/viewiStockNews/articleid/3880743

SAIC memo: “Estimation of Net Difference in Capital and O&M Costs for Once-through 

Versus Closed Cycle Cooling for New Generating Units at Existing Power Plants and for 

Repowering of Existing Generating Units” March 5, 2010.
Table 1. Comparison of the Capital Costs for Closed-Cycle Cooling Tower Retrofit at an Existing Plant to the Capital Cost of 

a New Greenfield Power Plant of a Similar Size

Old New Old New

Plant Type Conventional 

Coal

Scrubbed 

New Coal3

Conventional 

Combined Cycle3

Conventional 

Nuclear

Advanced 

Nuclear 

(Low)3

Advanced 

Nuclear 

(High)4

Plant Capacity (MW) 1000 1000 1000 1000 1000 1000

Unit Cooling Flow1 

(gpm/MW)

600 910

Existing Condenser Flow 

(gpm)

600,000 910,000

“Average” Difficulty 

Cooling Tower Retrofit 

Costs2 (million $)

$150 $228

“Difficult” Cooling Tower 

Retrofit Costs2 (million $)

$234 $355

Overnight Total Cost 

Factor ($2007/kw)

2,058 962 3,318 4,540

New Plant Overnight 

Capital Costs (million $)

$2,058 $962 $3,318 $4,540

All costs are in 2007 dollars.

1 Based on a delta T of 15°F and a heat rate of 9300 BTU/Kwh for coal and 10,200 BTU/Kwh for nuclear.

2 Based on EPRI Cooling Tower Retrofit Estimates.

3 Based on data in Table 8-2 of EIA Assumptions to Annual Energy Outlook 2009.

4 Based on FPL estimate in 2008 Synapse Report.
Table 2. Recent Capital Cost Estimates

Company and Plant Type of Unit Capacity Total Plant Costs1 Wet Cooling Tower Costs as 

% of Project Total

Florida Power and Light 

Turkey Point, Florida1

Nuclear 2200 MW 

(2 units)

$12.1 billion to

$17.8 billion.

<1%

Progress Energy Levy

County, Florida2

Nuclear 2200 MW 

(2 units)

$10.5 billion with 

financing costs the total 

becomes $13-14 billion.

<1%

Duke Energy Cliffside, 

North Carolina3

Coal - supercritical 800 MW $1.8 billion 2%

AMP-Ohio Meigs 

County, Ohio4

Coal – supercritical 960 MW $3 billion plus financing <2%

WPL Nelson Dewey 3, 

Wisconsin5

Coal and Biomass -

Circulating Fluid Bed

300 MW $1.3 billion plus 

financing

<1%

Costs are based on 2007/2008 estimates.

1

FPL has suspended all long term capital projects for the next 5 years due to rejection of $1.3 billion rate increase in January 2010 but 

continue to seek nuclear licenses.

2 Plant construction originally scheduled to begin construction in 2010, will be delayed 20 to 36 months due to economic and 

regulatory problems including rejection of $500 million rate hike.

3 Plant was 55% complete at end of 2009 with projected costs remaining at $1.8 Billion

4 Plant was cancelled in 2009 when cost estimate increased 37% to $4 Billion. There are tentative plans for a smaller gas-fired 

combined cycle plant instead.

5 Unit 3 was rejected by state regulators in November 2008 citing concerns about increased total cost of $1.3 billion and greenhouse 

gas emissions. 

Sources: Synapse 2008a; Synapse 2008b; AMP 2009; Journal Sentinel 2008; Miami Herald 2010; Charlotte Business Journal 2010;

iStockAnalyst 2010.