# MEMORANDUM

**Tetra Tech, Inc. 10306 Eaton Place, Suite 340**  **Fairfax, VA 22030 phone**  **703 -** **385 -**  **6000 fax**  **703 -** **385 -**  **6007** TO : Lisa Biddle, EPA FROM : John Sunda and Kelly Meadows DATE: February

12 , 2013 SUBJECT: Analysis of Cooling System Baseline Trends Using EIA Electricity Generator Data Data from the annual US Energy Information Administration (EIA) Form 860 survey was analyzed to determine the distribution of system type and age of electricity generator cooling systems to characterize industry trends in the usage of cooling system types for large electric generators . These trends are useful in the evaluation of t

he net impact of various regulatory requirements that affect the selection of cooling system type. Specifically, t he results of this analysis can help identify reasonable estimates of what portion of “new units” ( as defined in the 316(b) existing facility rule) would be designed and constructed with closed
- cycle cooling or the equivalent in the baseline
. 1 

### The most recent available data is from the 2011 Form EIA
- 860 survey. The file identified as “EnviroEquipY2011.xls” includes data specific to cooling systems
. Form EIA
- 860 “ collects data on the status of existing electric generating plants and associated equipment (including generators, boilers, cooling systems and flue gas desulfurization systems) in the United States, and those scheduled for initial commercial operation within 10 years of the specified reporting period
. ” The survey includes requests for data concerning “associated cooling systems
. ” The survey instructions define a cooling system as “ an equipment system that provides water to the condensers and includes water intakes and outlets, cooling towers and ponds, pumps, and pipes. Identify a single plant cooling system, not separate systems, unless systems are physically separated, e.g., have separate water intake and outlet structures, where each system can be operated independently.” (EIA , 2013) The data from the spreadsheet tab “cooling” was reviewed and found to include a sep arate row for each associated cooling system, with many plants reporting multiple systems. This analysis treats each system equally. D ata on cooling systems are required only f rom plants with a generating capacity of 100 MW or more . The exclusion of cooling systems for generating systems less than 100 MW limits the scope of this data to

1 In this case , baseline refers to what cooling system type would have been constructed in the absence of the existing facility rule or closed
- cycle cooling requirements for new units.

### larger plants that might typically require an intake flow of 60 to 120 mgd if operating a once -through

cooling system
. As a result, this analysis should include most Phase II generators and also many Phase III generators that operate flow reduction technologies such as closed
- cycle cooling. The Proposal TDD Exhibit 4
- 3 indicates that about 25% of in
- scope generating facilities have design intake flows of 2 to 100 mgd
. Thus, there should be a considerable amount of overlap with the 316(b) questionnaire database since many of those facilities use closed
- cycle cooling
. The EIA Form 860 database also includes a much larger universe of facilities since it includes facilities that would be considered out of scope for 316(b)
. 2 

### The data evaluated includes 1 , 640 cooling systems that are currently operating and is 80% larger than the EPA in
- scope estimate of 912 cooling systems ( see Proposal TDD Exhibit 4
- 8 )
. Since the EIA database is limited to cooling water systems , it is similar to the 316(b) questionnaire database in that it does not include generating facilities that do not use cooling water, such as combustion turbines, solar, or hydropower. By including a larger s cope of cool ing water using generators, t

his data is especially useful for estimating 316(b) compliance trends for new units since it includes the full range of system design and water sources both in
- scope and out
- of
- scope that would be available to new units. The analysis evaluated only those systems currently operating and those being constructed or planned. These are identified as :
 OP
- Operating (in commercial service or out of service less than 365 days)  CO
- Unit s under construction  PL
- Planned (expected to go into commercial service within 10 years) An important data element used in the analysis was the actual or projected “in
- service” year of the cooling system. This date is specific to the cooling system and may not necessarily be the same “in
service” date of the generating system. For example, the “in
- service” date of a retrofitted cooling system should be the date the retrofitted system began operation , provided the design is substantially different
. F or repowered systems where no cha nges were made to the cooling system, the “in
- service” date will likely be recorded as the start date for the original cooling system. 3 

### Thus, the data reflects the cooling system perspective only and there is no way to distinguish a cooling system associated with new Phase I units f rom those associated with stand
- alone/greenfield or repowered units at existing facilities
. In the analysis, the cooling systems were grouped by in
- service date by decade; pre
- 1950, 1960s, 1970s, 1980s, 1990s, 2000
-2011 (present), and future (under construction and planned). The database included codes for the numerous cooling system configurations and tower types listed in Tab les 1 and 2. Table 1 presents the number of cooling systems that fall within each group . Table 2 presents the distribution of cooling system types that began operation within each timeframe. Table 3 collapses many of the cooling

2 Out
- of
- scope systems include those that do not withdraw water from a surface water or withdraw less than 2 mgd
. 3 For example, the Bartow plant in Florida com

pleted a repowering project in 2009 where an entirely new combined cycle plant wa s built adjacent to the existing coal plant , which was demolished once the new system was completed. At this plant , the cooling system design and configuration did not change but many components such as the intake, pum ps and piping were replaced and rerouted. Even though the project was completed in 2009 , the 2011 EIA data for this plant continue to report an “in
- service” date of 1958
. Thus, it appears that a facility’s EIA survey response for thi s section of the survey wo n’t change from year to year , so it is unlikely the year in
- service data field wo uld be updated unless major changes to the cooling system design occurred.

### system types into groups that would be relevant to the 316(b) regulation . The last row in Table 3 also

shows the distribution of existing cooling systems by age. The database also included the “Design Cooling Water Flow Rate at 100 percent Load at Intake.” The average design intake flow per cooling system type and timeframe is shown in Table 4. The average design intake values are consistent with expected values with closed
- cycle being roughly an order of magnitude smaller than once through. **Baseline Analysis**  **of Closed -**  **Cycle Cooling** Of the cooling system types reported in the database, those that are likely to comply with a requirement to reduce flows commensurate with a closed
- cycle system include:

 Recirculating with pond/canal (impoundment)  Recirculating with forced draft tower(s)  Recirculating with induced draft tower(s)  Recirculating with natural draft tower(s)  Recirculating with forced draft hybrid tower(s) with dry cooling  Recirculating with induced draft hybrid tower(s) with dry cooling  Dry cooling  Other

4 

### The data in Table 3 cl early show a steady trend toward the use of closed
- cycle cooling , especially after the enactment of the Clean Water Act in 1972
. During the 1990’s , 8 4 % of new cooling systems were likely to be compliant with a requirement for a closed
- cycle recirculating system. The increase to 9 4 % in the 2000’ s likely reflects the influence of the Phase I 316(b) r ule , which was finalized in 2001
. Present day data indicate that 98 % of new cooling systems are likely to be compliant. This indicates that the baseline complia

nce value of 50% used in the new unit cost analysis in the proposed rule 5 

### was likely too conservative (low) . A more reasonable value for new construction would be somewhere between 83% and 98 %. The value of 83% represents 316(b) BPJ determinations prior to Phase I and should likely be the minimum for greenfield or stand
- alone units at existing facilities since Phase I would not apply to these units . The value of 98 % may be too high since the b asis for this number likely includes many Phase I systems that are required to use closed
- cycle cooling
. The midpoint value of 90% 6 

### may be a reasonable estimate for stand
- alone or greenfield new unit baseline compliance with a closed
- cycle cooling requirement . **Conclusion**

4 The individual data for those systems categorized as “other” were reviewed and it was determined that none used surface water as the source and so were deemed compliant as well. 5 This value of 50% was based on existing facility compliance data from EPA ’s 2000 technical questionnaire and did not incorporate recent trends. A value of 50% is consistent with the compliance estimate in this analysis for all existing cooling systems regardless of age , but may not be appropriate for characterizing new units
. 6 This value is consistent with EPA’s assumption that 70% of new unit capacity is regulated under Phase I. Since closed
- cycle cooling is required under Phase I, the 3% non
- com pliant portion (100%
- 97%) m ust only be associated with the 30% existing facility component. Thus, 3% (3 of 100) becomes 10% (3 of 30).

### A review of the EIA data shows a clear trend towards the use of closed
- cycle cooling in recent years for

new facilities, and presumably also for new units. As a result, EPA may wish to revise the previous estimates of baseline compliance for new units using the more recent data . Due to the higher rate of expected baseline compliance, is that the estimated economic impact (and benefits) of closed
- cycle cooling requirements for new units are much smaller than previously estimated
.

**References:** EIA. EIA Form 860 Annual Electric Generator Report

– Instructions. Accessed January 2013
. EIA. Database Spreadsheet: “EnviroEquipY2011 .xls ” Accessed January 2013
. EIA. Database Spreadsheet: “LayoutY2011.xls ” Accessed January 2013
.

### Tabl **e 1 EIA Form 860 Generator Cooling System**  **Type Counts**  **by In -**  **service Date Existing Cooling Systems**  **Under Construct**  **ion Planned**  **Existing**

**Total Future** 

**Total In**  **- service Dates**  **1920 -**  **1949 1950**  **-**

**1959 1960**  **-**

**1969 1970**  **- 1979**  **1980 -** 

**1989 1990**  **-**

**1999 2000**  **-**

**2011 2012**  **-**

**2022 2012**  **-**

**2022 1920**  **-**

**2011 2012**  **-**

**2022 Once** **- through Freshwater**  33 182 138 96 20 6 11 0 1 486 1 **Once -** **through Saltwater** 5 51 62 43 11 10 4 0 0 186 0 **Once -** **through Pond/Canal** 3 7 17 21 3 0 5 0 0 56 0 **Recirculating with Pond/Canal** 2 5 21 36 22 1 3 1 0 90 1 **Recirculating with Forced Draft Tower(s)**  2 21 26 64 59 20 116 5 5 308 10 **Recirculating with Induced Draft Tower(s)**  0 28 35 59 41 49 153 13 16 365 29 **Recirculating with Natural Draft Tower(s)**  0 0 11 34 39 6 2 3 0 92 3 **Recirculating with Forced Draft Hybrid Tower(s) with Dry Cooling**  0 0 0 0 0 0 2 1 0 2 1 **Recirculating with Induced Draft Hybrid Tower(s) with Dry Cooling**  0 0 0 0 0 0 2 0 0 2 0 **Dry Cooling** 0 0 0 1 2 7 42 0 12 52 12 **Other** 0 0 0 1 0 0 0 0 3 1 3 **Total** 45 294 310 355 197 99 340 23 37 1640 60

### Table 2 **EIA Form 860 Generator Cooling System Type Distribution**  **by In -**  **service Date Existing Cooling Systems**  **Under Constructio**  **n Planned**  **Existin**

**g Total Futur** 

**e Total**  **In -**  **service Dates 1920**  **- 1949**  **1950 -**  **1959 1960**  **- 1969**  **1970 -**  **1979 1980**  **- 1989**  **1990 -**  **1999 2000**  **- 2011**  **2012 -**  **2022 2012**  **- 2022**  **1920 -** 

**2011 2012**  **-**

**2022 Once** **- through Freshwater**  73% 62% 45% 27% 10% 6% 3% 0% 3% 30% 2% **Once -** **through Saltwater** 11% 17% 20% 12% 6% 10% 1% 0% 0% 11% 0% **Once -** **through Pond/Canal** 7% 2% 5% 6% 2% 0% 1% 0% 0% 3% 0% **Recirculating with Pond/Canal**  4% 2% 7% 10% 11% 1% 1% 4% 0% 5% 2% **Recirculating with Forced Draft Tower(s)** 4% 7% 8% 18% 30% 20% 34% 22% 14% 19% 17% **Recirculating with Induced Draft Tower(s)** 0% 10% 11% 17% 21% 49% 45% 57% 43% 22% 48% **Recirculating with Natural Draft Tower(s)**  0% 0% 4% 10% 20% 6% 1% 13% 0% 6% 5% **Recirculating with Forced Draft Hybrid Tower(s) with Dry Cooling**  0% 0% 0% 0% 0% 0% 1% 4% 0% 0% 2% **Recirculating with Induced Draft Hybrid Tower(s) with Dry Cooling**  0% 0% 0% 0% 0% 0% 1% 0% 0% 0% 0% **Dry Cooling**  0% 0% 0% 0% 1% 7% 12% 0% 32% 3% 20% **Other** 0% 0% 0% 0% 0% 0% 0% 0% 8% 0% 5% **Total** 100% 100% 100% 100% 100% 100% 100% 100% 100% 100% 100%

### Table 3 **EIA Form 860 Generator Cooling System Type Distribution by In -**  **service Date Existing Cooling**  **Systems Under**  **Constructio n**  **Planne**

**d Existin**  **g Total Futur** 

**e Total**  **In -**  **service Dates 1920**  **- 1949**  **1950 -**  **1959 1960**  **- 1969**  **1970 -**  **1979 1980**  **- 1989**  **1990 -**  **1999 2000**  **- 2011**  **2012 -**  **2022 2012**  **- 2022**  **1920 -** 

**2011 2012**  **-**

**2022 Once** **- Through (including Once**  **- through**  **Pond/Canal)** 91% 82% 70% 45% 17% 16% 6% 0% 3% 44% 2% **Recirculating Pond/Canal** 4% 2% 7% 10% 11% 1% 1% 4% 0% 5% 2% **Recirculating Tower** 4% 17% 23% 44% 71% 76% 80% 91% 57% 47% 70% **Recirculating Hybrid Tower** 0% 0% 0% 0% 0% 0% 1% 4% 0% 0% 2% **Dry Cooling** 0% 0% 0% 0% 1% 7% 12% 0% 32% 3% 20% **Likely 316(b) Com pliant**  **for Closed -**  **Cycle Cooling**  **1** 

### 9% 18% 30% 55% 83% 84% 94% 100% 97% 56% 98% **Cooling System Count**  45 294 310 355 197 99 340 23 37 1640 60 **Distribution of Cooling Systems 2**  3% 18% 19% 22% 12% 6% 21% 1.4% 2.3% 100% 3.7% 

### Includes only systems currently operating, under construction or planned in next 10 years 1 

### Includes Recirculating Towers, Dry Cooling and Other (all "Other" systems did not use surface water as source) 2 

### Distribution relative to total existing

### Table 4 **EIA Form 860 Generator Cooling System Average Intake Design Flow by Type and In**  **- service Date**  **Existing Cooling Systems Under**  **Constructio n**  **Planne**

**d Existin**  **g Total Futur** 

**e Total**  **In -**  **service Dates 1920**  **- 1949**  **1950 -** 

**1959 1960**  **-**

**1969 1970**  **- 1979**  **1980 -**  **1989 1990**  **- 1999**  **2000 -**  **2011 2012**  **- 2022**  **2012 -**  **2022 1920**  **-**

**2011 2012**  **-**

**2022 Units**  

### mgd **mgd mgd**  **mgd mgd**  **mgd mgd**  **mgd mgd**  **mgd mgd**  **Once -** **through Freshwater** 235 203 216 551 540 591 264
- 1 298 1 **Once -** **through Saltwater** 181 147 302 697 890 262 202
- - 378
- **Once -** **through Pond/Canal** 568 303 259 676 393
- 441
- - 461
- **Recirculating with Pond/Canal** 100 118 381 394 294 267 359 360
- 342 360 **Recirculating with Forced Draft Tower(s)**  4 47 38 70 51 32 24 3 2 42 2 **Recirculating with Induced Draft Tower(s)**  - 27 31 60 17 12 17 9 73 25 44 **Recirculating with Natural Draft**  **Tower(s)** - - 29 21 29 46 8 21
- 27 21 **Recirculating with Forced Draft Hybrid Tower(s) with Dry Cooling**  - - - - - - 4 1
- 4 1 **Recirculating with Induced Draft Hybrid Tower(s) with Dry Cooling**  - - - - - - 5
- - 5
- **Dry Cooling** - - - 0 0 0 0
- 0 0 0 **Other** - - - 2
- - - - 4 2 4 **All** 235 167 204 338 168 80 37 24 32 181 29