5-i 

CHAPTER 5. ENGINEERING ANALYSIS 

 

TABLE OF CONTENTS 

5.1 INTRODUCTION ........................................................................................................... 5-1

5.2 METHODOLOGY OVERVIEW .................................................................................... 5-1

5.3 REPRESENTATIVE EQUIPMENT CLASSES ............................................................. 5-2

5.3.1 Baseline Lamps and Representative Lamp Types ............................................... 5-4

5.4 HIGHER-EFFICACY REPLACEMENTS ..................................................................... 5-5

5.5 CANDIDATE STANDARD LEVELS............................................................................ 5-7

5.5.1 Candidate Standard Level for the ≥1900 K and ≤2800 K, ≥50 W and ≤1000 W, 

Clear, Enclosed Equipment Class ........................................................................ 5-9

5.5.2 Candidate Standard Levels for the >2800 K and ≤4500 K, ≥50 W and ≤400 W, 

Clear, Enclosed Equipment Class ...................................................................... 5-10

5.5.3 Candidate Standard Levels for the >2800 K and ≤4500 K, >400 W and ≤1000 W, 

Clear, Enclosed Equipment Class ...................................................................... 5-11

5.5.4 Candidate Standard Levels for the >2800 K and ≤4500 K, >1000 W and ≤2000 

W, Clear, Enclosed Equipment Class ................................................................ 5-12

5.5.5 Candidate Standard Levels Summary ................................................................ 5-13

5.6 HID SYSTEMS ............................................................................................................. 5-15

5.6.1 Ballasts ............................................................................................................... 5-15

5.6.2 Fixtures .............................................................................................................. 5-18

5.7 DETAILED DISCUSSION OF REPRESENTATIVE LAMP TYPES ........................ 5-18

5.7.1 70 W High-Pressure Sodium Representative Lamp Type ................................. 5-18

5.7.1.1 Baseline Models .................................................................................. 5-18

5.7.1.2 Candidate Standard Levels and More Efficacious Substitutes............ 5-19

5.7.1.3 Engineering Summary ......................................................................... 5-21

5.7.2 100 W High-Pressure Sodium Representative Lamp Type ............................... 5-22

5.7.2.1 Baseline Models .................................................................................. 5-22

5.7.2.2 Candidate Standard Levels and More Efficacious Substitutes............ 5-22

5.7.2.3 Engineering Summary ......................................................................... 5-24

5.7.3 250 W High-Pressure Sodium Representative Lamp Type ............................... 5-25

5.7.3.1 Baseline Models .................................................................................. 5-25

5.7.3.2 Candidate Standard Levels and More Efficacious Substitutes............ 5-25

5.7.3.3 Engineering Summary ......................................................................... 5-27

5.7.4 400 W High-Pressure Sodium Representative Lamp Type ............................... 5-28

5.7.4.1 Baseline Models .................................................................................. 5-28

5.7.4.2 Candidate Standard Levels and More Efficacious Substitutes............ 5-28

5.7.4.3 Engineering Summary ......................................................................... 5-30

5.7.5 1000 W High-Pressure Sodium Representative Lamp Type ............................. 5-31

5.7.5.1 Baseline Models .................................................................................. 5-31

5.7.5.2 Candidate Standard Levels and More Efficacious Substitutes............ 5-31

5.7.5.3 Engineering Summary ......................................................................... 5-33

5.7.6 100 W Mercury Vapor Representative Lamp Type ........................................... 5-34

5.7.6.1 Baseline Models .................................................................................. 5-34
5-ii

5.7.6.2 Candidate Standard Levels and More Efficacious Substitutes............ 5-34

5.7.6.3 Engineering Summary ......................................................................... 5-36

5.7.7 175 W Mercury Vapor Representative Lamp Type ........................................... 5-37

5.7.7.1 Baseline Models .................................................................................. 5-37

5.7.7.2 Candidate Standard Levels and More Efficacious Substitutes............ 5-37

5.7.7.3 Engineering Summary ......................................................................... 5-39

5.7.8 250 W Mercury Vapor Representative Lamp Type ........................................... 5-40

5.7.8.1 Baseline Models .................................................................................. 5-40

5.7.8.2 Candidate Standard Levels and More Efficacious Substitutes............ 5-40

5.7.8.3 Engineering Summary ......................................................................... 5-42

5.7.9 400 W Mercury Vapor Representative Lamp Type ........................................... 5-43

5.7.9.1 Baseline Models .................................................................................. 5-43

5.7.9.2 Candidate Standard Levels and More Efficacious Substitutes............ 5-43

5.7.9.3 Engineering Summary ......................................................................... 5-45

5.7.10 400 W Metal Halide Representative Lamp Type .............................................. 5-46

5.7.10.1 Baseline Models ................................................................................ 5-46

5.7.10.2 Candidate Standard Levels and More Efficacious Substitutes.......... 5-46

5.7.10.3 Engineering Summary ....................................................................... 5-48

5.7.11 1000 W Mercury Vapor Representative Lamp Type ......................................... 5-49

5.7.11.1 Baseline Models ................................................................................ 5-49

5.7.11.2 Candidate Standard Levels and More Efficacious Substitutes.......... 5-49

5.7.11.3 Engineering Summary ....................................................................... 5-51

5.7.12 1000 W Metal Halide Representative Lamp Type ............................................ 5-52

5.7.12.1 Baseline Models ................................................................................ 5-52

5.7.12.2 Candidate Standard Levels and More Efficacious Substitutes.......... 5-52

5.7.12.3 Engineering Summary ....................................................................... 5-54

5.7.13 2000 W Metal Halide Representative Lamp Type ............................................ 5-55

5.7.13.1 Baseline Models ................................................................................ 5-55

5.7.13.2 Candidate Standard Levels and More Efficacious Substitutes.......... 5-55

5.7.13.3 Engineering Summary ....................................................................... 5-57

5.7.14 Summary of Representative Lamp Type Candidate Standard Levels ............... 5-58

5.8 SCALING TO EQUIPMENT CLASSES NOT ANALYZED ...................................... 5-60

5.8.1 Bulb Finish ......................................................................................................... 5-61

5.8.2 Luminaire Characteristic .................................................................................... 5-61

5.8.3 CCT Range......................................................................................................... 5-62

5.8.4 Scaling Summary ............................................................................................... 5-62

5.9 SUMMARY OF ALL CANDIDATE STANDARD LEVEL EQUATIONS ............... 5-63

REFERENCES .......................................................................................................................... 5-65

LIST OF FIGURES 

Figure 5.5.1 Candidate Standard Level for ≥1900 K and ≤2800 K, ≥50 W and ≤1000 W, Clear, 

Enclosed Equipment Class ......................................................................................................... 5-10

Figure 5.5.2 Candidate Standard Levels for >2800 K and ≤4500 K, ≥50 W and ≤400 W, Clear, 

Enclosed Equipment Class ......................................................................................................... 5-11
5-iii

Figure 5.5.3 Candidate Standard Levels for >2800 K and ≤4500 K, >400 W and ≤1000 W, Clear, 

Enclosed Equipment Class ......................................................................................................... 5-12

Figure 5.5.4 Candidate Standard Level for >2800 K and ≤4500 K, >1000 W and ≤2000 W, 

Clear, Enclosed Equipment Class .............................................................................................. 5-13

Figure 5.5.5 Candidate Standard Level for ≥1900 K and ≤2800 K Representative Equipment 

Class ........................................................................................................................................... 5-14

Figure 5.5.6 Candidate Standard Levels for >2800 K and ≤4500 K Representative Equipment 

Classes........................................................................................................................................ 5-15

Figure 5.7.1 Candidate Standard Level for the 70 W HPS Representative Lamp Type ............ 5-20

Figure 5.7.2 Candidate Standard Level for the 100 W HPS Representative Lamp Type .......... 5-23

Figure 5.7.3 Candidate Standard Level for the 250 W HPS Representative Lamp Type .......... 5-26

Figure 5.7.4 Candidate Standard Level for the 400 W HPS Representative Lamp Type .......... 5-29

Figure 5.7.5 Candidate Standard Level for the 1000 W HPS Representative Lamp Type ........ 5-32

Figure 5.7.6 Candidate Standard Levels for the 100 W MV Representative Lamp Type ......... 5-35

Figure 5.7.7 Candidate Standard Levels for the 175 W MV Representative Lamp Type ......... 5-38

Figure 5.7.8 Candidate Standard Levels for the 250 W MV Representative Lamp Type ......... 5-41

Figure 5.7.9 Candidate Standard Levels for the 400 W MV Representative Lamp Type ......... 5-44

Figure 5.7.10 Candidate Standard Levels for the 400 W MH Representative Lamp Type ....... 5-47

Figure 5.7.11 Candidate Standard Levels for the 1000 W MV Representative Lamp Type ..... 5-50

Figure 5.7.12 Candidate Standard Levels for the 1000 W MH Representative Lamp Type ..... 5-53

Figure 5.7.13 Candidate Standard Level for the 2000 W MH Representative Lamp Type ...... 5-56

Figure 5.7.14 ≥1900 K and ≤2800 K Representative Equipment Class .................................... 5-58

Figure 5.7.15 >2800 K and ≤4500 K, ≥50 W and ≤400 W Representative Equipment Class .. 5-59

Figure 5.7.16 >2800 K and ≤4500 K, >400 W and ≤1000 W Representative Equipment Class .. 5-

59

Figure 5.7.17 >2800 K and ≤4500 K, >1000 W and ≤2000 W Representative Equipment Class 5-

60

LIST OF TABLES 

Table 5.3.1 Representative and Scaled Equipment Classes for HID Lamps ............................... 5-3

Table 5.3.2 Baseline Lamps ......................................................................................................... 5-5

Table 5.5.1 Candidate Standard Level for ≥1900 K and ≤2800 K, ≥50 W and ≤1000 W 

Equipment Class .......................................................................................................................... 5-9

Table 5.5.2 Candidate Standard Levels for >2800 K and ≤4500 K, ≥50 W and ≤400 W, Clear, 

Enclosed Equipment Class ......................................................................................................... 5-11

Table 5.5.3 Candidate Standard Levels for >2800 K and ≤4500 K, >400 W and ≤1000 W, Clear, 

Enclosed Equipment Class ......................................................................................................... 5-12

Table 5.5.4 Candidate Standard Level for >2800 K and ≤4500 K, >1000 W and ≤2000 W, Clear, 

Enclosed Equipment Class ......................................................................................................... 5-12

Table 5.5.5 Representative Equipment Class Candidate Standard Levels ................................ 5-13

Table 5.6.1 Representative Ballast Types .................................................................................. 5-16

Table 5.6.2 HID Ballast Efficiencies ......................................................................................... 5-17

Table 5.7.1 Baseline Lamp for the 70 W HPS Representative Lamp Type .............................. 5-19

Table 5.7.2 Summary of the CSL for the 70 W HPS Representative Lamp Type .................... 5-19

Table 5.7.3 Lamp Designs for the 70 W HPS Representative Lamp Type ............................... 5-21
5-iv

Table 5.7.4 Engineering Summary for 70 W HPS Representative Lamp Type ........................ 5-21

Table 5.7.5 Baseline Lamp for the 100 W HPS Representative Lamp Type ............................ 5-22

Table 5.7.6 Summary of the CSL for the 100 W HPS Representative Lamp Type .................. 5-23

Table 5.7.7 Lamp Designs for the 100 W HPS Representative Lamp Type ............................. 5-24

Table 5.7.8 Engineering Summary for 100 W HPS Representative Lamp Type ...................... 5-24

Table 5.7.9 Baseline Lamp for the 250 W HPS Representative Lamp Type ............................ 5-25

Table 5.7.10 Summary of the CSL for the 250 W HPS Representative Lamp Type ................ 5-25

Table 5.7.11 Lamp Designs for the 250 W HPS Representative Lamp Type ........................... 5-27

Table 5.7.12 Engineering Summary for 250 W HPS Representative Lamp Type .................... 5-27

Table 5.7.13 Baseline Lamp for the 400 W HPS Representative Lamp Type .......................... 5-28

Table 5.7.14 Summary of the CSL for the 400 W HPS Representative Lamp Type ................ 5-28

Table 5.7.15 Lamp Designs for the 400 W HPS Representative Lamp Type ........................... 5-30

Table 5.7.16 Engineering Summary for 400 W HPS Representative Lamp Type .................... 5-30

Table 5.7.17 Baseline Lamp for the 1000 W HPS Representative Lamp Type ........................ 5-31

Table 5.7.18 Summary of the CSL for the 1000 W HPS Representative Lamp Type .............. 5-31

Table 5.7.19 Lamp Designs for the 1000 W HPS Representative Lamp Type ......................... 5-33

Table 5.7.20 Engineering Summary for 1000 W HPS Representative Lamp Type .................. 5-33

Table 5.7.21 Baseline Lamps for the 100 W MV Representative Lamp Type .......................... 5-34

Table 5.7.22 Summary of the CSLs for the 100 W MV Representative Lamp Type ................ 5-35

Table 5.7.23 Lamp Designs for the 100 W MV Representative Lamp Type ............................ 5-36

Table 5.7.24 Engineering Summary for 100 W MV Representative Lamp Type ..................... 5-36

Table 5.7.25 Baseline Lamps for the 100 W MV Representative Lamp Type .......................... 5-37

Table 5.7.26 Summary of the CSLs for the 175 W MV Representative Lamp Type ................ 5-38

Table 5.7.27 Lamp Designs for the 175 W MV Representative Lamp Type ............................ 5-39

Table 5.7.28 Engineering Summary for 175 W MV Representative Lamp Type ..................... 5-39

Table 5.7.29 Baseline Lamps for the 250 W MV Representative Lamp Type .......................... 5-40

Table 5.7.30 Summary of the CSLs for the 250 W MV Representative Lamp Type ................ 5-41

Table 5.7.31 Lamp Designs for the 250 W MV Representative Lamp Type ............................ 5-42

Table 5.7.32 Engineering Summary for 250 W MV Representative Lamp Type ..................... 5-42

Table 5.7.33 Baseline Lamps for the 400 W MV Representative Lamp Type .......................... 5-43

Table 5.7.34 Summary of the CSLs for the 400 W MV Representative Lamp Type ................ 5-44

Table 5.7.35 Lamp Designs for the 400 W MV Representative Lamp Type ............................ 5-45

Table 5.7.36 Engineering Summary for 400 W MV Representative Lamp Type ..................... 5-45

Table 5.7.37 Baseline Lamps for the 400 W MH Representative Lamp Type .......................... 5-46

Table 5.7.38 Summary of the CSLs for the 400 W MH Representative Lamp Type ................ 5-47

Table 5.7.39 Lamp Designs for the 400 W MH Representative Lamp Type ............................ 5-48

Table 5.7.40 Engineering Summary for 400 W MH Representative Lamp Type ..................... 5-48

Table 5.7.41 Baseline Lamps for the 1000 W MV Representative Lamp Type ........................ 5-49

Table 5.7.42 Summary of the CSLs for the 1000 W MV Representative Lamp Type .............. 5-50

Table 5.7.43 Lamp Designs for the 1000 W MV Representative Lamp Type .......................... 5-51

Table 5.7.44 Engineering Summary for 1000 W MV Representative Lamp Type ................... 5-51

Table 5.7.45 Baseline Lamps for the 1000 W MH Representative Lamp Type ........................ 5-52

Table 5.7.46 Summary of the CSLs for the 1000 W MH Representative Lamp Type .............. 5-52

Table 5.7.47 Lamp Designs for the 1000 W MV Representative Lamp Type .......................... 5-54

Table 5.7.48 Engineering Summary for 1000 W MH Representative Lamp Type ................... 5-54

Table 5.7.49 Baseline Lamp for the 2000 W MH Representative Lamp Type ......................... 5-55
5-v

Table 5.7.50 Summary of the CSL for the 1000 W MV Representative Lamp Type ............... 5-55

Table 5.7.51 Lamp Designs for the 2000 W MV Representative Lamp Type .......................... 5-57

Table 5.7.52 Engineering Summary for 2000 W MH Representative Lamp Type ................... 5-57

Table 5.8.1 Scaling Factors ........................................................................................................ 5-62

Table 5.9.1 Equations for All CSLs ........................................................................................... 5-64
5-1

CHAPTER 5.ENGINEERING ANALYSIS 

5.1 INTRODUCTION 

The U.S. Department of Energy (DOE) performed an engineering analysis to study 

representative lamps and lamp-and-ballast systems used as substitutes for baseline lamps, to 

select candidate standard levels (CSLs), and to determine lamp-and-ballast system power ratings. 

DOE selects representative equipment classes to analyze. It then selects lamps that represent the 

baseline efficacy as well as more efficacious substitutes for those baseline lamps. DOE uses 

these more efficacious lamps to develop CSLs. While DOE establishes CSLs based on lamp 

designs for the engineering analysis, it also develops lamp-and-ballast systems for use in the lifecycle cost (LCC) analysis and national impact analysis (NIA) because lamps and ballasts operate 

together in practice. 

In energy conservation rulemakings for other equipment, DOE often develops costefficiency relationships in the engineering analysis. However, for this high-intensity discharge 

(HID) lamp rulemaking, DOE derives efficacy level and lamp-and-ballast system power for each 

representative system in the engineering analysis and end-user prices in the equipment price 

determination. By combining the results of the engineering analysis and the equipment price 

determination, DOE derives typical inputs for use in the LCC and NIA. See chapter 6 and 

appendix 6A of the interim technical support document (TSD) for discussion of DOE’s 

methodology for determining equipment prices. 

5.2 METHODOLOGY OVERVIEW

To the extent possible, DOE bases the engineering analysis on commercially available 

lamps that incorporate the design options identified in the technology assessment and screening 

analysis (chapters 3 and 4). However, where needed, DOE supplements these lamps with 

additional model lamps that use design options identified in the screening analysis (chapter 4 of 

the interim TSD). DOE took the following four steps in the engineering analysis: 

1. Select Representative Equipment Classes: DOE first reviews covered lamps and the 

associated equipment classes. When multiple equipment classes are needed, DOE selects 

certain classes as “representative” and concentrates its analytical effort on these classes. DOE 

selects representative equipment classes primarily because of their high market volumes. For 

those equipment classes that are not analyzed, DOE extrapolates the CSLs from 

representative equipment classes to other equipment classes. 

2. Select Baseline Lamps: For each equipment class, DOE selects a baseline lamp as a reference 

point against which to measure changes resulting from energy conservation standards. 

Typically, a baseline lamp is the most common, least efficacious lamp sold in a given 

equipment class. For this interim analysis, DOE uses performance data presented in 

manufacturer catalogs to determine lamp efficacy. DOE also considers other lamp 

characteristics in choosing the most appropriate baseline for each equipment class. These 

characteristics include the lamp’s starting method, wattage, and technology (i.e., highpressure sodium [HPS], metal halide [MH], or mercury vapor [MV]). For some of the 

representative lamp types, DOE selects multiple baseline models to ensure consideration of 
5-2

different high-volume lamps and their associated customer economics. For example, MV 

lamps are the least efficacious lamp option for some equipment classes; however, MV lamps 

represent a very small portion of the market because many customers have already 

transitioned to MH technology. For this reason, DOE selects both an MV and an MH lamp as 

baselines for certain equipment classes. 

3. Identify More Efficacious Substitutes: DOE selects higher-efficacy lamps as replacements for 

each of the baseline lamps. DOE only considers design options that meet the criteria outlined 

in the screening analysis (chapter 4 of the interim TSD). Although DOE generally selects 

commercially available lamps as substitutes, DOE also developed model lamps for the ≥1900 

Kelvin (K) and ≤2800 K, ≥50 W and ≤1000 W, clear, enclosed equipment classes. See 

section 5.4 for more detail. 

Because customers are typically unable or unwilling to change fixture spacing within their 

facilities and spaces, DOE is analyzing more efficacious, reduced-wattage substitutes that 

maintain mean lumens within 10 percent of the baseline when possible. Mean lumens are a 

measure of light output midway through the rated life of a lamp, and a 10 percent change is a 

common parameter used by lighting designers to specify acceptable substitute products on 

the basis of light output. 

4. Determine Candidate Standard Levels. After identifying more efficacious substitutes for 

each baseline lamp, DOE develops CSLs. DOE bases its analysis on three factors: (1) the 

design options associated with the specific lamps studied; (2) the ability of lamps across 

wattages to comply with the standard level of a given equipment class;a

and (3) the maximum 

technologically feasible efficacy level. 

The sections that follow discuss how DOE applies this methodology to each equipment 

class to create the engineering analysis. 

5.3 REPRESENTATIVE EQUIPMENT CLASSES 

As discussed in the market and technology assessment (chapter 3 of the interim TSD), 

DOE created equipment classes based on correlated color temperature (CCT), wattage, bulb 

finish, and luminaire characteristic. Of these equipment classes, DOE chose to analyze four as 

representative. For CCT, DOE considered the ≥1900 K to ≤2800 K and >2800 K to ≤4500 K 

ranges to be representative. The ≥1900 K and ≤2800 K range includes all HPS lamps, a 

significant market segment (about one-third of HID lamp shipments in 2008).1 Based on lamp 

catalogs and manufacturer interviews, DOE found that MH and MV lamps are available in both 

the >2800 K to ≤4500 K and >4500 K and <7000 K ranges, but the former of the two ranges 

includes the more commonly shipped MH and MV lamps. For bulb finish, DOE determined that 

clear lamps were more commonly shipped than coated lamps.bFinally, for luminaire 

 

a

 CSLs span multiple lamps of different wattages. In selecting CSLs, DOE considered whether these multiple lamps 

can meet the standard levels. 

b

 Clear lamps are more commonly shipped within these two representative CCT ranges for both HPS and MH lamps. 

The MV lamps that are in the >2800 K and ≤4500 K equipment classes are all coated. Because these equipment 

classes are made up predominantly of MH lamps and there is only one option for MV lamps in these classes, DOE 
5-3

characteristic, DOE determined that enclosed-rated MH lamps are more commonly shipped than 

open-rated MH lamps.cTable 5.3.1 lists the representative equipment classes and those classes 

not analyzed directly (scaled equipment classes). 

Table 5.3.1 Representative and Scaled Equipment Classes for HID Lamps

CCT Range Wattage Bulb 

Finish*

Luminaire 

Characteristic**

Representative or Scaled 

Equipment Class

1900 K and 2800 

K

50 W and 

1000 W

Clear

Enclosed Representative Equipment Class

Open Scaled

Coated

Enclosed Scaled

Open Scaled

2800 K and 4500 

K

50 W and 

400 W

Clear

Enclosed Representative Equipment Class

Open Scaled

Coated

Enclosed Scaled

Open Scaled

400 W and 

1000 W

Clear

Enclosed Representative Equipment Class

Open Scaled

Coated

Enclosed Scaled

Open Scaled

1000 W and 

2000 W

Clear

Enclosed Representative Equipment Class

Open Scaled

Coated

Enclosed Scaled

Open Scaled

4500 K and 7000 

K

50 W and 

400 W

Clear

Enclosed Scaled

Open Scaled

Coated

Enclosed Scaled

Open Scaled

400 W and 

1000 W

Clear

Enclosed Scaled

Open Scaled

Coated

Enclosed Scaled

Open Scaled

1000 W and 

2000 W

Clear

Enclosed Scaled

Open Scaled

Coated

Enclosed Scaled

Open Scaled

* MV lamps regardless of bulb finish are placed in the clear equipment classes for their respective CCT and wattage.

** MV and HPS lamps are placed in the enclosed equipment classes for their respective wattage and CCT.

 

will refer to these classes as being “clear,” although all the MV lamps within them will be coated. Chapter 3 of the 

interim TSD describes the equipment class categorization of MV lamps. 

c

 While HPS and MV lamps do not have open vs. enclosed luminaire characteristic, DOE determined in chapter 3 of 

the interim TSD that HPS and MV lamps would be placed in the enclosed equipment classes for their respective 

CCT and wattage. 
5-4

5.3.1 Baseline Lamps and Representative Lamp Types 

Once DOE identified the representative equipment classes for analysis, it selected 

baseline lamps to analyze in each class. Because no Federal energy conservation standards exist 

for HID lamps, the baseline lamps represent the most common, least efficacious lamps sold 

within the equipment class. For each baseline lamp, DOE selected more efficacious replacement 

lamps to measure potential energy-saving improvements. DOE refers to the baseline lamp and its 

more efficacious replacements collectively herein as a “representative lamp type.” The 

representative lamp type is named by its baseline unit. For example, the 400 W MV 

representative lamp type refers to the 400 W MV baseline lamp and its more efficacious 

replacements. 

In certain cases in which two lamp technologies (e.g., MV and MH) are included in the 

same representative lamp type, DOE selected multiple baseline lamps to ensure consideration of 

different consumer economics. For example, MV lamps are the least efficacious lamp option for 

some equipment classes; however, MV lamps represent a small portion of the market because 

many customers have already transitioned to MH technology. For this reason, DOE selects both 

a MV lamp and a MH lamp as baselines for certain representative lamp types in the >2800 K and 

≤4500 K equipment classes. 

For the ≥1900 K and ≤2800 K, ≥50 W and ≤1000 W, clear, enclosed equipment class 

(hereafter referred to as the ≥1900 K and ≤2800 K representative equipment class), DOE chose 

five baselines. After examining catalog data and interviewing manufacturers, DOE decided to 

analyze HPS lamps with wattages of 70, 100, 250, 400, and 1000 W as baselines. While a small 

number of ceramic metal halide (CMH) lamps exist in this CCT range, HPS lamps are the most 

popular technology by a wide margin and thus were the lamps chosen as baseline lamps for this 

representative equipment class. DOE chose to analyze baseline HPS lamps at 70, 100, 250, and 

400 W after learning from manufacturers that these were wattages at which HPS lamps are most 

commonly sold. DOE also chose to analyze a 1000 W HPS baseline in order to characterize the 

high wattage end of the equipment class. These five baselines are summarized below in Table 

5.3.2.

For the >2800 K and ≤4500 K, ≥50 W and ≤400 W, clear, enclosed equipment class 

(hereafter referred to as the >2800 K and ≤4500 K, ≥50 W and ≤400 W representative equipment 

class), DOE chose to analyze nine baseline lamps, spanning five different representative lamp 

types. After examining catalog data and interviewing manufacturers, DOE concluded that only 

MV and MH technologies are available in this equipment class. Because MV lamps are 

consistently the least efficacious lamps in this CCT range, DOE selected the most common MV 

lamps as baselines. When a MH lamp could serve as a higher-efficacy replacement lamp for a 

MV baseline lamp, DOE analyzed both the MV lamp and the least-efficacious MH lamp as 

baselines. Lastly, some MH lamps were chosen as baselines even when they did not offer the 

same lumen package as a MV baseline lamp. Including these MH baseline lamps ensured DOE 

accurately characterized the HID lamp market because these MH baseline lamps represented 

high shipment volumes. DOE decided to analyze MV lamps with wattages of 100, 175, 250, and 

400 W and MH lamps with wattages of 70, 100, 175, 250, and 400 W as baselines. These nine 

baselines are summarized below in Table 5.3.2. 
5-5

For the >2800 K and ≤4500 K, >400 W and ≤ 1000 W, clear, enclosed equipment class 

(hereafter referred to as the >2800 K and ≤4500 K, >400 W and ≤ 1000 W representative 

equipment class), DOE analyzed two baselines. Based on catalog availability and manufacturer 

feedback, DOE found the most common, least efficient lamp in this equipment class to be a 1000 

W MV lamp and thus chose to analyze a 1000 W MV baseline. DOE also selected a 1000 W MH 

baseline lamp to analyze. This baseline was included because 1000 W MH lamps represent high 

shipment volumes based on catalog availability and manufacturer input. These two baseline 

lamps for the >2800 K and ≤4500 K, >400 W and ≤ 1000 W representative equipment class are 

shown below in Table 5.3.2.

For the >2800 K and ≤4500 K, >1000 W and ≤2000 W, clear, enclosed equipment class 

(hereafter referred to as the >2800 K and ≤4500 K, >1000 W and ≤2000 W representative 

equipment class), DOE analyzed only one baseline. In order to characterize the highest wattage 

of the equipment class, DOE chose a 2000 W probe-start MH lamp as the baseline, as shown 

below in Table 5.3.2. MV lamps are not present in this equipment class because this rulemaking 

is only considering standards for MV lamps that are ≥50 W and ≤1000 W. 

Table 5.3.2 Baseline Lamps 

CCT Range Wattage Bulb 

Finish*

Luminaire 

Characteristic**

Representative 

Lamp Type

Baseline Lamp 

Type

Baseline 

Wattage

1900 K and 

2800 K

≥50 W and 

1000 W Clear Enclosed

70 W HPS HPS 70

100 W HPS HPS 100

250 W HPS HPS 250

400 W HPS HPS 400

1000 W HPS HPS 1000

>2800 K and 

4500 K

≥50 W and 

400 W Clear Enclosed

100 W MV

MV 100

MH 70

175 W MV

MV 175

MH 100

250 W MV

MV 250

MH 175

400 W MV

MV 400

MH 250

400 W MH MH 400

>400 W and 

1000 W Clear Enclosed

1000 W MV MV 1000

1000 W MH MH 1000

>1000 W and 

2000 W Clear Enclosed 2000 W MH MH 2000

*MV lamps regardless of bulb finish are placed in the clear equipment classes for their respective CCT and wattage.

** MV and HPS lamps are placed in the enclosed equipment classes for their respective wattage and CCT.

5.4 HIGHER-EFFICACY REPLACEMENTS

After choosing a baseline lamp for each representative lamp type, DOE searched for 

commercially available HID lamps that would serve as more efficacious substitutes on the basis 
5-6

of initial efficacy. When identifying lamps that could replace baselines, DOE considered a 

number of criteria. Most importantly, more efficacious substitutes were selected to save energy 

and, when possible, have mean lumens within 10 percent of the mean lumens of the baseline 

lamp. DOE also sought to keep other characteristics as similar as possible, such as initial lumen 

output, operating orientation, rated life, color rendering index (CRI), bulb shape, and base type. 

DOE did not identify any commercially available lamps in the ≥1900 K and ≤2800 K 

representative equipment class that had technologies to improve the efficacy above the baseline 

level. DOE considered four options for modeling higher-efficacy replacements. 

First, DOE examined the possibility of using low CCT (2800 K) CMH lamps as 

replacements for the HPS lamps. DOE found a small number of these CMH lamps advertised for 

use in applications in which HPS lamps are typically used. DOE identified commercially 

available replacements for two of the five HPS baselines (70 W and 100 W). The low CCT and 

high efficacy of these CMH lamps make them a suitable alternative for HPS lamps. The CMH 

lamps, however, are made by a single manufacturer and incorporate proprietary technology. 

Because DOE was unable to confirm that similar 2800 K CMH lamps could be manufactured 

without proprietary technology, DOE did not analyze higher-efficacy replacements based on this 

design option. 

A second approach DOE considered was adapting HPS lamps that are currently offered 

in Europe. DOE found that the maximum efficacies of European HPS lamps below 450 W are 

typically higher than those of American HPS lamps.d However, this trend in efficacy between 

European and American HPS lamps did not hold true for wattages greater than 450 W. DOE 

identified several design differences between European and American lamps. When comparing 

lamps of the same wattage, European lamps tend to operate at higher voltages. This may be due 

to the different supply voltages offered on the two continents and results in lamps being designed 

with different electrical characteristics. This difference also prevents their use in American 

applications that are optimized to different voltages. If modified for the American electrical 

system, European lamps may decrease in efficacy. In the absence of a consistent trend, DOE 

could not conclusively determine that European lamps achieved higher levels of efficacy than 

American lamps. Therefore, DOE did not use European lamps to develop a replacement option 

for the ≥1900 K and ≤2800 K representative equipment class. 

A third method DOE considered was using non-cycling HPS lamps to replace standard 

HPS lamps. Standard HPS lamps exhibit end-of-life cycling, which occurs at the end of the 

lamp’s operating life as the voltage of the lamp increases beyond the ballast’s capability to 

sustain the arc. When this happens, the lamp extinguishes, cools down, and turns on again. The 

cycling pattern will repeat until the lamp is replaced, though customers often find it difficult to 

identify and find a lamp that has reached this cycling point when it is in a large group of lamps. 

If the lamp is not replaced within a reasonable period of time, the ballast is also at risk of failing 

permanently. To combat this issue, manufacturers introduced non-cycling HPS lamps that 

prevent cycling by changing the contents of the arc tube, the electrode’s emissive coating 

material, and the arc tube wall temperature. Instead of cycling, these lamps will either change 

 

d

 This may be in part due to the presence of European efficacy standards for HPS lamps with wattages less than or 

equal to 605 W. 
5-7

noticeably in color (from yellow light to a cooler white light), indicating to the customer that it is 

time to replace the lamp, or simply not light at all. While non-cycling HPS lamps tend to be more 

efficacious at low wattages, DOE compared efficacies for cycling and non-cycling lamps across 

all available wattages to determine if an overall trend in efficacy difference was present. DOE 

determined that non-cycling lamps are not consistently more efficacious than cycling lamps, and 

therefore did not analyze non-cycling lamps as more efficacious replacements for the ≥1900 K 

and ≤2800 K representative equipment class. 

Finally, DOE learned through manufacturer interviews that the efficacy of HPS may be 

improved by changing the arc tube material. Through its own research, DOE found academic 

papers that indicated potential increases in efficacy through the use of sapphire, or single crystal 

aluminum oxide, instead of the industry standard ceramic, or polycrystalline alumina (PCA) 

material.2Sapphire has superior light transmission characteristics that would allow for a 

moderate improvement in efficacy. Based on independent research and feedback from both HID 

manufacturers and glass manufacturers, DOE estimates that light output increases by five percent 

when changing from ceramic to sapphire arc tubes. This moderate improvement in light output, 

however, comes with some difficulties. In addition to the significant increase in cost required to 

manufacture, sapphire introduces unique design difficulties because of its tendency to expand 

differently along each of its three axes. When sapphire is formed into an arc tube, this asymmetry 

in material expansion may result in rupture of the arc tube. Although this technology is not 

currently commercially available, several manufacturers have previously produced an HPS lamp 

with a sapphire arc tube, the first appearing in the late 1970s. As such, DOE determined that

sapphire arc tubes provide the best approach to increasing the efficacy of standard HPS lamps. 

To calculate the wattage and efficacy of the equal-lumen, reduced-wattage, modeled CSL 

1 lamp, DOE first plotted five modeled lamps of equal wattage to all five baseline lamps (70, 

100, 250, 400, and 1000 W), but with a five percent increase in efficacy. Then, DOE fit a power 

regression curve to the five more efficacious lamps. Using this power regression curve, DOE 

determined the percent reduction in wattage necessary to create an equal-lumen, reduced-wattage 

lamp relative to the baseline. For example, the 70 W baseline lamp in the ≥1900 K and ≤2800 K 

representative equipment class has 6300 initial lumens. Using the five percent increase in 

efficacy, DOE modeled a 67 W HPS lamp with a sapphire arc tube that also has 6300 initial 

lumens. All of the modeled CSL 1 lamps in the ≥1900 K and ≤2800 K representative equipment 

class were assumed to have the same lamp characteristics (i.e., CCT, initial lumens, mean 

lumens, operating orientation, bulb finish, luminaire characteristic, and rated life) as the 

corresponding baseline lamp. 

As discussed in Chapter 4 of the interim TSD, DOE is still considering whether sapphire 

arc tube HPS lamps pass the four screening criteria to become a design option in the engineering 

analysis. However, for the interim TSD, DOE presents results for the potential CSL 1 based on 

sapphire arc tube technology. 

5.5 CANDIDATE STANDARD LEVELS

In its analysis of available data, DOE found that initial lamp efficacy tends to increase 

with increased wattage. DOE considered two options to capture this trend when establishing 

CSLs: (1) a constant-value approach, in which the same standard is established for all lamps 
5-8

within an equipment class, and (2) an equation-based approach, in which a relationship between 

lamp input power and initial lamp efficacy is determined for each equipment class. To consider a 

constant-value approach, in which all lamp wattages within an equipment class are required to 

meet a single standard, DOE would have to create several additional equipment classes to 

accommodate the range of wattages encompassed by a representative lamp type. For example, in 

the >2800 K to ≤4500 K CCT range, DOE could create an equipment class for lamps with 

wattages between 100 W and 250 W that would encompass the 250 W MV baseline and the 

more efficacious, lower-wattage probe-start, pulse-start, and CMH replacements (the 250 W MV 

representative lamp type). However, when analyzing potential equipment class divisions based 

on wattage, DOE noticed that the wattage of the highest-efficacy replacements for certain 

baselines overlapped with a neighboring equipment class. For example, the 100 W CMH 

replacement for the 250 W MV baseline lamp in the above equipment class has the same wattage 

as: (1) a 100 W pulse-start MH replacement for a 175 W MV baseline lamp and (2) a 100 W MV 

baseline lamp. Furthermore, a constant-value approach could encourage a market shift to the 

higher-wattage end of any equipment class, as those lamps are naturally able to achieve higher 

efficacy than lower wattage lamps. For these reasons, DOE decided to pursue an equation-based 

approach in this rulemaking. 

When developing CSL equations, DOE modeled each equation to represent a particular 

design option. To represent a particular design option, DOE designed the CSL equation to just 

allow the representative units of a particular design option (the results of the representative unit 

selection process are discussed in section 5.7). For example, DOE developed a CSL equation for 

each more efficacious replacement for a MV baseline, such as a probe-start MH, pulse-start MH, 

and CMH lamp. After analyzing available products, DOE noticed that the same design options 

were not available across all lamp wattages. For example, CMH lamps were only available 

between 50 and 400 W.e

 Similarly, pulse-start quartz MH lamps are not available above 1000 W. 

Because more efficacious lamp design options are only available at certain lamp wattages, and 

DOE had already established that lamp wattage offers unique utility, DOE established separate 

equipment classes based on lamp wattage. DOE established separate equipment classes for lamps 

in the >2800 K and ≤4500 K, and >4500 K and <7000 K CCT ranges with wattages ≥50 W and 

≤400 W, >400 W and ≤1000 W, and >1000 W and ≤2000 W. Because lamps in the ≥1900 K and 

≤2800 K CCT range are almost all HPS lamps, DOE found no need to separate this CCT range 

by wattage range. 

DOE analyzed each equipment class to determine the appropriate CSLs. To develop 

equations, DOE used power function regression curves to best fit the representative units in each 

equipment class, according to an equation of the form: 

Initial lamp efficacy (lm/W) = Coefficient * (Lamp input power [W]) ^ Exponent 

Using the available data, DOE calculated the coefficient and exponent for each CSL equation. 

For the equipment classes described above, in which fewer technologies were available to 

improve efficacy, DOE utilized either linear or constant equation forms instead of the power 

function equation form.

 

e

 An 830 W and an 860 W CMH lamp are available from one manufacturer using proprietary technology. 
5-9

5.5.1 Candidate Standard Level for the ≥1900 K and ≤2800 K, ≥50 W and ≤1000 W, 

Clear, Enclosed Equipment Class

For the ≥1900 K and ≤2800 K, ≥50 W and ≤1000 W, clear, enclosed equipment class, 

DOE identified one potential CSL above the baseline, represented by HPS lamps with a sapphire 

arc tube, described in section 5.4, which will only be included in the engineering analysis for 

later stages of this rulemaking if DOE positively concludes that this technology option meets the 

screening criteria, per the discussion in chapter 4 of this interim TSD. By plotting initial lamp 

efficacy as a function of input power for lamps in this equipment class, DOE determined that the 

data is best modeled by a power function with an exponent less than one (a concave power 

function). This relationship is characterized by a positive slope that decreases with increased 

values of input power. The CSL for the ≥1900 K and ≤2800 K, ≥50 W and ≤ 1000 W, clear, 

enclosed equipment class is depicted below in Table 5.5.1 and Figure 5.5.1. 

Table 5.5.1 Candidate Standard Level for ≥1900 K and ≤2800 K, ≥50 W and ≤1000 W 

Equipment Class 

Candidate Standard Level Design Option Equation

CSL 1 Modeled HPS lm/W = 54.0 * W0.13
5-10

Figure 5.5.1 Candidate Standard Level for ≥1900 K and ≤2800 K, ≥50 W and ≤1000 W, 

Clear, Enclosed Equipment Class 

5.5.2 Candidate Standard Levels for the >2800 K and ≤4500 K, ≥50 W and ≤400 W, 

Clear, Enclosed Equipment Class 

In the >2800 K to ≤4500 K CCT range, which contains the majority of MV and MH 

lamps, DOE observed that the same lamp technologies were not available at all available lamp 

wattages. Therefore, DOE separated equipment classes by wattage as discussed in chapter 3 of 

the interim TSD. For all products in these equipment classes, DOE sought to maintain continuity 

of the CSL equations across all covered wattages. Ensuring continuity between equipment 

classes prevents lamps of slightly different input power being subject to very different standards. 

In a case where a higher wattage lamp is subject to a less stringent standard, the market could be 

encouraged to shift to increased wattage, negating potential energy savings. 

For lamps with wattages ≥50 W and ≤400 W, DOE identified three CSLs above the 

baseline, which represent commercially available probe-start MH, pulse-start MH, and CMH 

lamps. As was done for the ≥1900 K and ≤2800 K, ≥50 W and ≤ 1000 W, clear, enclosed 

equipment class, DOE plotted initial lamp efficacy as a function of lamp input power for lamps 

in this equipment class and determined that the data was best modeled by a power function with 

an exponent less than one (a concave power function). CSLs 1 and 2, which represent MH lamps 

with the traditional quartz arc tube, both have an exponent value of 0.10. This differs from CSL 

3, which has a value of 0.13 and represents MH lamps with ceramic arc tubes. The higher 

exponent results in a steeper slope throughout the wattage range. The CSLs for lamps ≥50 W and 

≤400 W are depicted in Table 5.5.2 and Figure 5.5.2 below.

80

90

100

110

120

130

140

0 200 400 600 800 1000

Initial Lamp Efficacy (lm/W)

Lamp Wattage (W)

CSL 1
5-11

Table 5.5.2 Candidate Standard Levels for >2800 K and ≤4500 K, ≥50 W and ≤400 W, 

Clear, Enclosed Equipment Class 

Candidate Standard Level Design Option Equation

CSL 1 Probe MH lm/W = 45.5 * W0.10

CSL 2 Pulse MH lm/W = 50.7 * W0.10

CSL 3 CMH lm/W = 48.7 * W0.13

Figure 5.5.2 Candidate Standard Levels for >2800 K and ≤4500 K, ≥50 W and ≤400 W, 

Clear, Enclosed Equipment Class 

5.5.3 Candidate Standard Levels for the >2800 K and ≤4500 K, >400 W and ≤1000 W, 

Clear, Enclosed Equipment Class 

For lamps with wattages >400 W and ≤1000 W, DOE analyzed two representative lamp 

types. In this equipment class, a linear trend of the following form proved to be the best fit for 

the available data: 

lm/W = coefficient * (lamp input power) + constant 

The coefficient of CSL 2 was determined by fitting a line, anchored to the CSL 2 

endpoint of the ≥50 W and ≤400 W range, such that the CSL 2 pulse-start representative lamps 

exceeded this standard level. Because DOE observed that quartz MH lamps follow the same 

relationship between 50 W and 400 W, the slope of the CSL 1 equation was assumed to be equal 

to that of CSL 2 for lamps >400 W and ≤1000 W. The constants for the CSLs in this wattage 

range were determined by extending a line with this slope through the endpoints of the curves in 

the ≥50 W and ≤400 W range to maintain continuity throughout the entire covered wattage 

60

70

80

90

100

110

120

0 50 100 150 200 250 300 350 400

Initial Lamp Efficacy (lm/W)

Lamp Wattage (W)

CSL 1

CSL 2

CSL 3
5-12

range. The CSLs for lamps >400 W and ≤1000 W are depicted in Table 5.5.3 and Figure 5.5.3

below. 

Table 5.5.3 Candidate Standard Levels for >2800 K and ≤4500 K, >400 W and ≤1000 W, 

Clear, Enclosed Equipment Class 

Candidate Standard Level Design Option Equation

CSL 1 Probe-start MH lm/W = 0.021 * W + 74.3

CSL 2 Pulse-start MH lm/W = 0.021 * W + 83.8

Figure 5.5.3 Candidate Standard Levels for >2800 K and ≤4500 K, >400 W and ≤1000 W, 

Clear, Enclosed Equipment Class 

5.5.4 Candidate Standard Levels for the >2800 K and ≤4500 K, >1000 W and ≤2000 W, 

Clear, Enclosed Equipment Class 

For lamps with wattages >1000 W and ≤2000 W, DOE analyzed only one representative 

lamp. The CSL 1 equation represents probe-start technology and is a constant efficacy 

requirement of 95.3 lm/W, determined by connecting a horizontal line (slope of zero) through the 

1000 W endpoint of CSL 1 in the >400 W and ≤1000 W range. The CSL for lamps >1000 W and 

≤2000 W is depicted in Table 5.5.4 and Figure 5.5.4 below. 

Table 5.5.4 Candidate Standard Level for >2800 K and ≤4500 K, >1000 W and ≤2000 W, 

Clear, Enclosed Equipment Class 

Candidate Standard Level Design Option Equation

CSL 1 Probe MH lm/W = 95.3

60

70

80

90

100

110

120

400 500 600 700 800 900 1000

Initial Lamp Efficacy (lm/W)

Lamp Wattage (W)

CSL 1

CSL 2
5-13

Figure 5.5.4 Candidate Standard Level for >2800 K and ≤4500 K, >1000 W and ≤2000 W, 

Clear, Enclosed Equipment Class 

5.5.5 Candidate Standard Levels Summary 

A summary of the candidate standard level descriptions and equations for all analyzed 

equipment classes is presented in Table 5.5.5, Figure 5.5.5, and Figure 5.5.6.

Table 5.5.5 Representative Equipment Class Candidate Standard Levels 

CCT Range Wattage Range CSL Design Option Equation

≥1900 K and ≤2800 K ≥50 W and ≤1000 W CSL 1* Modeled HPS lm/W = 54.0 * W0.13

>2800 K and ≤4500 K

≥50 W and ≤400 W

CSL 1 Probe MH lm/W = 45.5 * W0.10

CSL 2 Pulse MH lm/W = 50.7 * W0.10

CSL 3 CMH lm/W = 48.7 * W0.13

>400 W and ≤1000 W

CSL 1 Probe MH lm/W = 0.021 * W + 74.3

CSL 2 Pulse MH lm/W = 0.021 * W + 83.8

>1000 W and ≤2000 W CSL 1 Probe MH lm/W = 95.3

*This CSL 1 will be considered in the engineering analysis only if DOE concludes that sapphire arc tubes meet all 

four screening criteria.

60

70

80

90

100

110

120

1000 1200 1400 1600 1800 2000

Initial Lamp Efficacy (lm/W)

Lamp Wattage (W)

CSL 1
5-14

Figure 5.5.5 Candidate Standard Level for ≥1900 K and ≤2800 K Representative 

Equipment Classf

 

f

 For this equipment class, CSL 1 will be considered in the engineering analysis only if DOE positively concludes 

that sapphire arc tubes meet all four screening criteria. 

80

90

100

110

120

130

140

0 200 400 600 800 1000

Initial Lamp Efficacy (lm/W)

Lamp Wattage (W)

CSL 1
5-15

Figure 5.5.6 Candidate Standard Levels for >2800 K and ≤4500 K Representative 

Equipment Classes 

5.6 HID SYSTEMS

In this rulemaking, DOE is only considering standards for HID lamps. However, HID 

lamps are just one component of an HID lighting system. HID lamps require carefully specified 

ballasts in order to regulate the current and power supplied to the lamp. These lamp-and-ballast 

systems are then housed in an HID lamp fixtureg

in order to protect the components, enable it to 

be mounted in the desired location, and direct the light to the target area. When considering 

changes to HID lamps, DOE recognizes the importance of also analyzing the impact on both the 

ballast and the fixture. 

5.6.1 Ballasts 

Because HID lamps require a ballast to operate, DOE pairs each representative HID lamp 

with a representative ballast to develop representative lamp-and-ballast systems. Through catalog 

review and manufacturer interviews, DOE learned that a new ballast is generally required when 

an HID lamp is replaced with a more efficacious substitute. This is often because the more 

efficacious substitute lamp has a lower wattage. DOE has found that the performance 

characteristics of a ballast—most importantly ballast efficiency—change with wattage. 

Therefore, in order to properly identify an energy conservation standard’s impact on system 

performance, the correct ballast needs to be paired with each representative lamp. For this 

rulemaking, DOE assumes that any change in lamp wattage necessitates a change in ballast. 

 

g

 Here, DOE uses the term “fixture” to refer to the enclosure that houses the lamp and ballast. 

60

70

80

90

100

110

120

0 500 1000 1500 2000

Initial Lamp Efficacy (lm/W)

Lamp Wattage (W)

CSL 1

CSL 2

CSL 3
5-16

In addition to a change in wattage, more efficacious lamps often utilize different 

technology. For example, when moving from a MV lamp to a MH lamp, the change in 

technology necessitates a change in ballast. A ballast for a MV lamp is designed and operated 

differently than a ballast for a MH lamp, and those differences affect the performance 

characteristics of the ballast, including the ballast efficiency. For this rulemaking, DOE assumes 

that changing from one lamp technology to another (e.g., MV to MH, probe-start MH to pulsestart MH, quartz MH to CMH) necessitates a change in ballast. 

DOE analyzed HID ballast catalogs and received manufacturer input to determine the 

ballast type that is most commonly used with each representative lamp type. In the HID market, 

ballasts can be classified as either magnetic or electronic. Magnetic ballasts are larger, more 

robust to high temperature and voltage transients, and less expensive than electronic ballasts. 

Electronic ballasts have recently become more popular due to their high efficiencies, but they 

still have lower market share than magnetic ballasts. When DOE analyzed the HPS ballasts on 

the market, the available products were almost entirely magnetic. Similarly, for MV lamps, DOE 

found that magnetic MV ballasts comprised the vast majority of the market. For these reasons, 

DOE paired magnetic ballasts with the HPS and MV representative lamps. When determining 

which type of ballast to use for the representative MH lamps, DOE analyzed the probe-start MH, 

pulse-start MH, and CMH lamps separately. DOE determined that magnetic ballasts are more 

commonly used by probe-start and pulse-start MH lamps than electronic ballasts. In surveying 

the current market for CMH lamps, however, DOE found that electronic ballasts are typically 

paired with CMH lamps. Therefore, DOE used an electronic MH ballast with all representative 

CMH lamps and a magnetic MH ballast with all representative probe-start and pulse-start MH 

lamps. Table 5.6.1 below summarizes the representative ballast types used with each 

representative lamp type. 

Table 5.6.1 Representative Ballast Types 

Lamp Technology Lamp Starting Method Lamp Arc Tube Material Ballast Type

HPS N/A N/A HPS magnetic

MV N/A N/A MV magnetic

MH Probe Quartz MH magnetic

MH Pulse Quartz MH magnetic

MH Pulse Ceramic MH electronic

For each representative ballast type and wattage combination, DOE calculated 

representative ballast efficiencies. For pulse-start magnetic MH ballasts subject to energy 

conservation standards, DOE chose the efficiency of a ballast that just meets the current 

standards. The current standards, which apply only to MH ballasts installed in new fixtures, 

effectively eliminate probe-start ballasts by setting a minimum efficiency that cannot be met by 

commercially available probe-start ballasts. However, probe-start MH ballasts can still be bought 

as replacement ballasts, so DOE calculated the ballast efficiency of probe-start magnetic MH 

ballasts subject to energy conservation standards using efficiency data found in manufacturer 

catalogs. DOE assigned an efficiency for probe-start magnetic MH ballasts at each wattage based 

on the average efficiency found in manufacturer catalogs for all probe-start magnetic MH 

ballasts at that wattage. For all the remaining ballast types (i.e., magnetic MH ballasts that are 

not subject to current standards, HPS magnetic ballasts, MV magnetic ballasts, and MH 
5-17

electronic ballasts), DOE also used the ballast efficiency data found in manufacturer catalogs, 

averaging the efficiencies of all ballasts available at each ballast type and wattage combination. 

For the higher-efficacy HPS lamps modeled with sapphire arc tubes at CSL 1, DOE assumed the 

ballast efficiencies were the same as those of the baseline system. DOE did this because for each 

of the HPS sapphire arc tube models, the change in lamp wattage is relatively small and thus 

DOE assumed the change in ballast efficiency to be negligible. Table 5.6.2 below lists all of the 

ballast type and wattage combinations, and the ballast efficiency used for each combination. 

Once DOE determined the efficiency of each representative ballast type, DOE used the 

ballast efficiency and lamp wattage to calculate the overall system power. The total power 

required, in watts, was calculated by dividing the lamp wattage by the ballast efficiency. By 

using this total system energy figure, instead of only the wattage of the lamp, DOE ensures that it 

will consider CSLs that increase lamp efficacy while also decreasing system power. These 

overall system power calculations are summarized below in Table 5.6.2. 

Table 5.6.2 HID Ballast Efficiencies 

Ballast Type Lamp Wattage

W

Ballast Efficiency

%

Lamp-and-Ballast System Power

W

HPS Magnetic

70 76.9 91

100 78.1 128

250 84.3 297

400 86.4 463

1000 91.8 1089

MV Magnetic

100 83.3 120

175 85.4 205

250 87.4 286

400 89.1 449

1000 92.4 1083

MH Magnetic

70 72.0 97

100 76.9 130

150 81.0 185

175 88.0 199

200 88.0 227

250 88.0 284

320 88.0 364

400 88.0 455

750 90.7 827

875 90.2 970

1000 91.8 1089

1500 91.9 1632

2000 95.0 2105

MH 

Electronic

50 89.3 56

70 89.7 78

100 90.1 111

150 90.4 166

250 92.5 270
5-18

5.6.2 Fixtures 

As described previously, when replacing an HID lamp with a more efficacious substitute, 

a change in ballast is often required. After seeking input from both HID lamp and HID fixture 

manufacturers, DOE determined that these changes to the lamp-and-ballast system also 

necessitate a change in HID lamp fixture. This fixture replacement is needed for several reasons. 

Replacement lamp-and-ballast systems will likely be a different size, and will likely not fit into 

the existing fixture. Additionally, HID lamp manufacturers and HID lamp fixture manufacturers 

advised that the cost to retrofit an existing fixture with a new system is generally too large for a 

customer to find this method worthwhile. Changing lamp-and-ballast systems will also result in 

non-optimal optics with the existing fixture, because fixtures are designed to optimize the light 

output for a specific lamp-and-ballast system. Lastly, retrofitting an old fixture with a new lampand-ballast system creates safety concerns and will result in the decertifying of the fixture’s UL 

rating.hFor this rulemaking, DOE assumes that changes in the lamp-and-ballast system 

necessitate a change in fixture. DOE models fixture replacements as impacting the price of a 

lamp-and-ballast system to the customer, but not impacting the performance. 

See Appendix 6A of the interim TSD for more information on the pricing of HID 

fixtures. 

5.7 DETAILED DISCUSSION OF REPRESENTATIVE LAMP TYPES

The following sections discuss the criteria used and the lamp models selected for each of 

the 13 representative lamp types used in the engineering analysis.

5.7.1 70 W High-Pressure Sodium Representative Lamp Type 

The ≥1900 K and ≤2800 K representative equipment class contains five representative 

lamp types. In this section, DOE analyzes the 70 W HPS representative lamp type for this 

equipment class. 

5.7.1.1 Baseline Models 

DOE selected baseline lamps as reference points from which DOE measured changes 

resulting from potential energy conservation standards. As discussed in section 5.2, a baseline 

lamp is typically the most common, least efficacious lamp sold in a given equipment class. To 

determine energy savings and changes in price, DOE compared each higher efficacy level with 

the baseline unit. 

DOE considered a number of criteria when selecting which commercially available lamp 

would serve as a baseline. First, as discussed in section 5.3.1, DOE selected a 70 W HPS lamp as 

a baseline based on its relatively high shipment volume. Then, DOE identified typical 

characteristics for these types of lamps (i.e., CRI, rated life, bulb shape, base type, and operating 

 

h

 UL, or Underwriters Laboratories, is an organization that independently certifies a wide variety of product safety, 

including luminaires. When HID fixture manufacturers submit products for safety certification, the UL certification 

is only valid using the lamp-and-ballast system that was sold and tested with the fixture. Any modifications to the 

fixture, such as replacing the lamp and/or ballast will void the UL certification. 
5-19

orientation).i Among all 70 W HPS lamps within the representative equipment class that had the 

most common characteristics, DOE selected one of the least efficacious lamps as the baseline. 

Table 5.7.1 lists the characteristics of the 70 W HPS baseline lamp. 

Table 5.7.1 Baseline Lamp for the 70 W HPS Representative Lamp Type 

CSL Lamp 

Type

Wattage 

W

CCT 

K

Initial 

Lumens

Initial 

Efficacy 

lm/W

Mean 

Lumens

Mean 

Efficacy 

lm/W

Operating 

Orientation

Baseline HPS 70 2100 6300 90.0 5850 83.6 Universal

5.7.1.2 Candidate Standard Levels and More Efficacious Substitutes 

The following discussion identifies the steps and technologies associated with each CSL 

DOE considered for the 70 W HPS representative lamp type. As discussed in section 5.4, DOE 

did not identify any commercially available lamps with an increased efficacy in the ≥1900 K and 

≤2800 K representative equipment class, and instead modeled a more efficacious lamp based on 

a sapphire arc tube. A CSL based on such modeled lamps will only be considered in the 

engineering analysis for future stages of the rulemaking if DOE positively determines that this 

technology option meets all four screening criteria as discussed in chapter 4 of the interim TSD. 

If so, this modeled HPS lamp will represent the maximum improvement in efficacy that is 

technologically feasible, as required by section 325(o) of EPCA. (42 U.S.C. 6295(o)). 

Table 5.7.2 Summary of the CSL for the 70 W HPS Representative Lamp Typef

CSL Design Option Initial Efficacy Requirementj

CSL 1 Modeled HPS lm/W = 54.0 * W0.13

 

Figure 5.7.1 illustrates CSL 1 on a plot with the representative units for the 70 W HPS 

representative lamp type. The squares represent the representative unit selected by DOE for a 

baseline lamp and a modeled sapphire replacement. 

 

i

 DOE attempted, wherever possible, to choose both baseline and representative units that were universal operating 

orientation, meaning the lamp can operate functionally when mounted in any direction. Lamps that can only operate 

in one position (vertical, horizontal, base up, etc.) can be optimized for that position, and thus increase their efficacy, 

whereas manufacturers typically find there to be an efficacy penalty associated with ensuring a lamp can operate in 

any position. Because the ability to operate in any position is useful for customers, DOE wanted to take care not to 

select any representative units that would eliminate universal-orientation lamps and only allow for a single 

orientation lamps. 

j

 Throughout this chapter, W is defined as the rated wattage of the HID lamp. 
5-20

Figure 5.7.1 Candidate Standard Level for the 70 W HPS Representative Lamp Typef

80

82

84

86

88

90

92

94

96

98

100

50 60 70 80 90 100

Initial Lamp Efficacy (lm/W)

Lamp Wattage (W)

CSL 1

Baseline Representative Unit

CSL 1 Representative Unit
5-21

Table 5.7.3 Lamp Designs for the 70 W HPS Representative Lamp Typef

CSL Lamp Type Wattage 

W

CCT 

K

Initial 

Lumens

Initial 

Efficacy 

lm/W

Mean 

Lumens

Mean 

Efficacy 

lm/W

Operating 

Orientation

Baseline HPS 70 2100 6300 90.0 5850 83.6 Universal

CSL 1 Modeled HPS 67 2100 6300 93.9 5850 87.2 Universal

5.7.1.3 Engineering Summary 

The following table summarizes the engineering characteristics for the baseline and each lamp replacement option for the 70 

W HPS representative lamp type. 

Table 5.7.4 Engineering Summary for 70 W HPS Representative Lamp Typef CSL Lamp Type Arc Tube Wattage

W

CCT

K

Initial Lumens

Initial Efficacy lm/W

Mean Lumens

Change in 

Mean 

Lumens 

From 

Baseline 

%

Mean Efficacy lm/W

Operating Orientation

Bulb Finish

Ballast Type

Ballast Efficiency

%

Lamp-and-Ballast 

System Power 

W

Baseline HPS Ceramic 70 2100 6300 90.0 5850 -- 83.6 Universal Clear HPS

magnetic 76.9 91

CSL 1

Modeled 

HPS Sapphire 67 2100 6300 93.9 5850 0.0 87.2 Universal Clear HPSmagnetic 76.9 87
5-22

As discussed in section 5.4, DOE notes that the increased efficacy lamp was modeled to 

have the same initial and mean lumen output as the baseline lamp. The increased efficacy is 

obtained by the modeled sapphire arc tube lamps requiring fewer watts to achieve the same light 

output. 

5.7.2 100 W High-Pressure Sodium Representative Lamp Type 

The ≥1900 K and ≤2800 K representative equipment class contains five representative 

lamp types. In this section, DOE analyzes the 100 W HPS representative lamp type for this 

equipment class. 

5.7.2.1 Baseline Models 

DOE selected baseline lamps as reference points from which DOE measured changes 

resulting from potential energy conservation standards. As discussed in section 5.2, a baseline 

lamp is typically the most common, least efficacious lamp sold in a given equipment class. To 

determine energy savings and changes in price, DOE compared each higher efficacy level with 

the baseline unit. 

DOE considered a number of criteria when selecting which commercially available lamp 

would serve as a baseline. First, as discussed in section 5.3.1, DOE selected a 100 W HPS lamp 

as a baseline based on its relatively high shipment volume. Then, DOE identified typical 

characteristics for these types of lamps (i.e., CRI, rated life, bulb shape, base type, and operating 

orientation). Among all 100 W HPS lamps within the representative equipment class that had the 

most common characteristics, DOE selected one of the least efficacious lamps as the baseline. 

Table 5.7.5 lists the characteristics of the 100 W HPS baseline lamp. 

Table 5.7.5 Baseline Lamp for the 100 W HPS Representative Lamp Type 

CSL Lamp 

Type

Wattage 

W

CCT 

K

Initial 

Lumens

Initial 

Efficacy 

lm/W

Mean 

Lumens

Mean 

Efficacy 

lm/W

Operating 

Orientation

Baseline HPS 100 2000 9500 95.0 8550 85.5 Universal

5.7.2.2 Candidate Standard Levels and More Efficacious Substitutes 

The following discussion identifies the steps and technologies associated with each CSL 

DOE considered for the 100 W HPS representative lamp type. As discussed in section 5.5, DOE 

did not identify any commercially available lamps with an increased efficacy in the ≥1900 K and 

≤2800 K representative equipment class, and instead developed a modeled more efficacious lamp 

based on a sapphire arc tube. A CSL based on such modeled lamps will only be considered in the 

engineering analysis for future stages of the rulemaking if DOE positively determines that this 

technology option meets all four screening criteria as discussed in chapter 4 of the interim TSD. 

If so, this modeled HPS lamp will represent the maximum improvement in efficacy that is 

technologically feasible, as required by section 325(o) of EPCA. (42 U.S.C. 6295(o)). 
5-23

Table 5.7.6 Summary of the CSL for the 100 W HPS Representative Lamp Typef

CSL Design Option Initial Efficacy Requirementj

CSL 1 Modeled HPS lm/W = 54.0 * W0.13

 

Figure 5.7.2 illustrates CSL 1 on a plot with the representative units for the 100 W HPS 

representative lamp type. The squares represent the representative unit selected by DOE for a 

baseline lamp and a modeled sapphire replacement. 

Figure 5.7.2 Candidate Standard Level for the 100 W HPS Representative Lamp Typef

85

87

89

91

93

95

97

99

101

103

105

80 85 90 95 100 105 110

Initial Lamp Efficacy (lm/W)

Lamp Wattage (W)

CSL 1

Baseline Representative Unit

CSL 1 Representative Unit
5-24

Table 5.7.7 Lamp Designs for the 100 W HPS Representative Lamp Typef

CSL Lamp Type Wattage 

W

CCT 

K

Initial 

Lumens

Initial 

Efficacy 

lm/W

Mean 

Lumens

Mean 

Efficacy 

lm/W

Operating 

Orientation

Baseline HPS 100 2000 9500 95.0 8550 85.5 Universal

CSL 1 Modeled HPS 96 2000 9500 99.2 8550 89.2 Universal

5.7.2.3 Engineering Summary 

The following table summarizes the engineering characteristics for the baseline and each lamp replacement option in the 100 

W HPS representative lamp type. 

Table 5.7.8 Engineering Summary for 100 W HPS Representative Lamp Typef CSL Lamp Type Arc Tube Wattage

W

CCT

K

Initial Lumens

Initial Efficacy lm/W

Mean Lumens

Change in 

Mean 

Lumens 

From 

Baseline 

%

Mean Efficacy lm/W

Operating Orientation

Bulb Finish

Ballast Type

Ballast Efficiency

%

Lamp-and-Ballast System 

Power Use

W

Baseline HPS Ceramic 100 2000 9500 95.0 8550 -- 85.5 Universal Clear HPS 

magnetic 78.1 128

CSL 1 Modeled 

HPS Sapphire 96 2000 9500 99.2 8550 0.0 89.2 Universal Clear HPS magnetic 78.1 123

As discussed in section 5.4, DOE notes that the increased efficacy lamp was modeled to have the same initial and mean lumen 

output as the baseline lamp. The increased efficacy is obtained by the modeled sapphire arc tube lamps requiring fewer watts to 

achieve the same light output.
5-25

5.7.3 250 W High-Pressure Sodium Representative Lamp Type 

The ≥1900 K and ≤2800 K representative equipment class contains five representative 

lamp types. In this section, DOE analyzes the 250 W HPS representative lamp type for this 

equipment class. 

5.7.3.1 Baseline Models 

DOE selected baseline lamps as reference points from which DOE measured changes 

resulting from potential energy conservation standards. As discussed in section 5.2, a baseline 

lamp is typically the most common, least efficacious lamp sold in a given equipment class. To 

determine energy savings and changes in price, DOE compared each higher efficacy level with 

the baseline unit. 

DOE considered a number of criteria when selecting which commercially available lamp 

would serve as a baseline. First, as discussed in section 5.3.1, DOE selected a 250 W HPS lamp 

as a baseline based on its relatively high shipment volume. Then, DOE identified typical 

characteristics for these types of lamps (i.e., CRI, rated life, bulb shape, base type, and operating 

orientation).i Among all 250 W HPS lamps within the representative equipment class that had the 

most common characteristics, DOE selected one of the least efficacious lamps as the baseline. 

Table 5.7.9 lists the characteristics of the 250 W HPS baseline lamp. 

Table 5.7.9 Baseline Lamp for the 250 W HPS Representative Lamp Type 

CSL Lamp 

Type

Wattage 

W

CCT 

K

Initial 

Lumens

Initial 

Efficacy 

lm/W

Mean 

Lumens

Mean 

Efficacy 

lm/W

Operating 

Orientation

Baseline HPS 250 2100 27,000 108.0 24,300 97.2 Universal

5.7.3.2 Candidate Standard Levels and More Efficacious Substitutes 

The following discussion identifies the steps and technologies associated with each CSL 

DOE considered for the 250 W HPS representative lamp type. As discussed in section 5.4, DOE

did not identify any commercially available lamps with an increased efficacy in the ≥1900 K and 

≤2800 K representative equipment class, and instead developed a modeled more efficacious lamp 

based on a sapphire arc tube. A CSL based on such modeled lamps will only be considered in the 

engineering analysis for future stages of the rulemaking if DOE positively determines that this 

technology option meets all four screening criteria as discussed in chapter 4 of the interim TSD. 

If so, this modeled HPS lamp will represent the maximum improvement in efficacy that is 

technologically feasible, as required by section 325(o) of EPCA. (42 U.S.C. 6295(o)). 

Table 5.7.10 Summary of the CSL for the 250 W HPS Representative Lamp Typef

CSL Design Option Initial Efficacy Requirementj

CSL 1 Modeled HPS lm/W = 54.0 * W0.13

 
5-26

Figure 5.7.3 illustrates CSL 1 on a plot of the representative units for the 250 W HPS 

representative lamp type. The squares represent the representative unit selected by DOE for a 

baseline lamp and a modeled sapphire replacement. 

Figure 5.7.3 Candidate Standard Level for the 250 W HPS Representative Lamp Typef

100

102

104

106

108

110

112

114

116

118

120

230 235 240 245 250 255 260 265 270

Initial Lamp Efficacy (lm/W)

Lamp Wattage (W)

CSL 1

Baseline Representative Unit

CSL 1 Representative Unit
5-27

Table 5.7.11 Lamp Designs for the 250 W HPS Representative Lamp Typef

CSL Lamp Type Wattage 

W

CCT 

K

Initial 

Lumens

Initial 

Efficacy 

lm/W

Mean 

Lumens

Mean 

Efficacy 

lm/W

Operating 

Orientation

Baseline HPS 250 2100 27,000 108.0 24,300 97.2 Universal

CSL 1 Modeled HPS 240 2100 27,000 112.7 24,300 101.4 Universal

5.7.3.3 Engineering Summary 

The following table summarizes the engineering characteristics for the baseline and each lamp replacement option in the 250 

W HPS representative lamp type. 

Table 5.7.12 Engineering Summary for 250 W HPS Representative Lamp Typef CSL Lamp Type Arc Tube Wattage W CCT

K

Initial Lumens

Initial Efficacy lm/W

Mean Lumens

Change in 

Mean 

Lumens 

From 

Baseline 

%

Mean Efficacy lm/W

Operating Orientation

Bulb Finish

Ballast Type

Ballast Efficiency

%

Lamp-and-Ballast System 

Power

W

Baseline HPS Ceramic 250 2100 27,000 108.0 24,300 -- 97.2 Universal Clear HPS

magnetic 84.3 297

CSL 1 Modeled 

HPS Sapphire 240 2100 27,000 112.7 24,300 0.0 101.4 Universal Clear HPS magnetic 84.3 284

As discussed in section 5.4, DOE notes that the increased efficacy lamp was modeled to have the same initial and mean lumen 

output as the baseline lamp. The increased efficacy is obtained by the modeled sapphire arc tube lamps requiring fewer watts to 

achieve the same light output.
5-28

5.7.4 400 W High-Pressure Sodium Representative Lamp Type 

The ≥1900 K and ≤2800 K representative equipment class contains five representative 

lamp types. In this section, DOE analyzes the 400 W HPS representative lamp type for this 

equipment class. 

5.7.4.1 Baseline Models 

DOE selected baseline lamps as reference points from which DOE measured changes 

resulting from potential amended energy conservation standards. As discussed in section 5.2, a 

baseline lamp is typically the most common, least efficacious lamp sold in a given equipment 

class. To determine energy savings and changes in price, DOE compared each higher efficacy 

level with the baseline unit. 

DOE considered a number of criteria when selecting which commercially available lamp 

would serve as a baseline. First, as discussed in section 5.3.1, DOE selected 400 W HPS lamps 

as a baseline based on its relatively high shipment volume. Then, DOE identified typical 

characteristics for these types of lamps (i.e., CRI, rated life, bulb shape, base type, and operating 

orientation).i Among all 400 W HPS lamps within the representative equipment class that had the 

most common characteristics, DOE selected one of the least efficacious lamps as the baseline. 

Table 5.7.13 lists the characteristics of the 400 W HPS baseline lamp. 

Table 5.7.13 Baseline Lamp for the 400 W HPS Representative Lamp Type 

CSL Lamp 

Type

Wattage 

W

CCT 

K

Initial 

Lumens

Initial 

Efficacy 

lm/W

Mean 

Lumens

Mean 

Efficacy 

lm/W

Operating 

Orientation

Baseline HPS 400 2000 47,000 117.5 39,950 99.9 Universal

5.7.4.2 Candidate Standard Levels and More Efficacious Substitutes 

The following discussion identifies the steps and technologies associated with each CSL 

DOE considered for the 400 W HPS representative lamp type. As discussed in section 5.4, DOE 

did not identify any commercially available lamps with an increased efficacy in the ≥1900 K and 

≤2800 K representative equipment class, and instead developed a modeled more efficacious lamp 

based on a sapphire arc tube. A CSL based on such modeled lamps will only be considered in the 

engineering analysis for future stages of the rulemaking if DOE positively determines that this 

technology option meets all four screening criteria as discussed in chapter 4 of the interim TSD. 

If so, this modeled HPS lamp will represent the maximum improvement in efficacy that is 

technologically feasible, as required by section 325(o) of EPCA. (42 U.S.C. 6295(o)). 

Table 5.7.14 Summary of the CSL for the 400 W HPS Representative Lamp Typef

CSL Design Option Initial Efficacy Requirementj

CSL 1 Modeled HPS lm/W = 54.0 * W0.13

 
5-29

Figure 5.7.4 illustrates CSL 1 on a plot of the representative units for the 400 W HPS 

representative lamp type. The squares represent the representative unit selected by DOE for a 

baseline lamp and a modeled sapphire replacement. 

Figure 5.7.4 Candidate Standard Level for the 400 W HPS Representative Lamp Typef

115

116

117

118

119

120

121

122

123

124

125

370 380 390 400 410 420

Initial Lamp Efficacy (lm/W)

Lamp Wattage (W)

CSL 1

Baseline Representative Unit

CSL 1 Representative Unit
5-30

Table 5.7.15 Lamp Designs for the 400 W HPS Representative Lamp Typef

CSL Lamp Type Wattage 

W

CCT 

K

Initial 

Lumens

Initial 

Efficacy 

lm/W

Mean 

Lumens

Mean 

Efficacy 

lm/W

Operating 

Orientation

Baseline HPS 400 2000 47,000 117.5 39,950 99.9 Universal

CSL 1 Modeled HPS 383 2000 47,000 122.6 39,950 104.3 Universal

5.7.4.3 Engineering Summary 

The following table summarizes the engineering characteristics for the baseline and each lamp replacement option in the 400 

W HPS representative lamp type. 

Table 5.7.16 Engineering Summary for 400 W HPS Representative Lamp Typef CSL Lamp Type Arc Tube Wattage

W

CCT

K

Initial Lumens

Initial Efficacy lm/W

Mean Lumens

Change in 

Mean 

Lumens 

From 

Baseline 

%

Mean Efficacy lm/W

Operating Orientation

Bulb Finish

Ballast Type

Ballast Efficiency

%

Lamp-and-Ballast System 

Power

W

Baseline HPS Ceramic 400 2000 47,000 117.5 39,950 -- 99.9 Universal Clear HPS 

magnetic 86.4 463

CSL 1

Modeled 

HPS Sapphire 383 2000 47,000 122.6 39,950 0.0 104.3 Universal Clear HPS magnetic 86.4 444

As discussed in section 5.4, DOE notes that the increased efficacy lamp was modeled to have the same initial and mean lumen 

output as the baseline lamp. The increased efficacy is obtained by the modeled sapphire arc tube lamps requiring fewer watts to 

achieve the same light output.
5-31

5.7.5 1000 W High-Pressure Sodium Representative Lamp Type 

The ≥1900 K and ≤2800 K representative equipment class contains five representative 

lamp types. In this section, DOE analyzes the 1000 W HPS representative lamp type for this 

equipment class. 

5.7.5.1 Baseline Models 

DOE selected baseline lamps as reference points from which DOE measured changes 

resulting from potential energy conservation standards. As discussed in section 5.2, a baseline 

lamp is typically the most common, least efficacious lamp sold in a given equipment class. To 

determine energy savings and changes in price, DOE compared each higher efficacy level with 

the baseline unit. 

DOE considered a number of criteria when selecting which commercially available lamp 

would serve as a baseline. First, as discussed in section 5.3.1, DOE selected a 1000 W HPS lamp 

as a baseline based on its relatively high shipment volume. Then, DOE identified typical 

characteristics for these types of lamps (i.e., CRI, rated life, bulb shape, base type, and operating 

orientation).i Among all 1000 W HPS lamps within the representative equipment class that had 

the most common characteristics, DOE selected one of the least efficacious lamps as the 

baseline. Table 5.7.17 lists the characteristics of the 1000 W HPS baseline lamp. 

Table 5.7.17 Baseline Lamp for the 1000 W HPS Representative Lamp Type

CSL Lamp 

Type

Wattage 

W

CCT 

K

Initial 

Lumens

Initial 

Efficacy 

lm/W

Mean 

Lumens

Mean 

Efficacy 

lm/W

Operating 

Orientation

Baseline HPS 1000 2100 130,000 130.0 117,000 117.0 Universal

5.7.5.2 Candidate Standard Levels and More Efficacious Substitutes 

The following discussion identifies the steps and technologies associated with each CSL 

DOE considered for the 1000 W HPS representative lamp type. As discussed in section 5.4, DOE 

did not identify commercially available lamps with an increased efficacy in the ≥1900 K and 

≤2800 K representative equipment class, and instead developed a modeled more efficacious lamp 

based on a sapphire arc tube. A CSL based on such modeled lamps will only be considered in the 

engineering analysis for future stages of the rulemaking if DOE positively determines that this 

technology option meets all four screening criteria as discussed in chapter 4 of the interim TSD. 

If so, this modeled HPS lamp will represent the maximum improvement in efficacy that is 

technologically feasible, as required by section 325(o) of EPCA. (42 U.S.C. 6295(o)). 

Table 5.7.18 Summary of the CSL for the 1000 W HPS Representative Lamp Typef

CSL Design Option Initial Efficacy Requirementj

CSL 1 Modeled HPS lm/W = 54.0 * W0.13

 
5-32

Figure 5.7.5 illustrates CSL 1 on a plot of the representative units for the 1000 W HPS 

representative lamp type. The squares represent the representative unit selected by DOE for a 

baseline lamp and a modeled sapphire replacement. 

Figure 5.7.5 Candidate Standard Level for the 1000 W HPS Representative Lamp Typef

128

129

130

131

132

133

134

135

136

137

138

950 960 970 980 990 1000

Initial Lamp Efficacy (lm/W)

Lamp Wattage (W)

CSL 1
5-33

Table 5.7.19 Lamp Designs for the 1000 W HPS Representative Lamp Typef

CSL Lamp Type Wattage 

W

CCT 

K

Initial 

Lumens

Initial 

Efficacy 

lm/W

Mean 

Lumens

Mean 

Efficacy 

lm/W

Operating 

Orientation

Baseline HPS 1000 2100 130,000 130.0 117,000 117.0 Universal

CSL 1 Modeled HPS 958 2100 130,000 135.7 117,000 122.1 Universal

5.7.5.3 Engineering Summary 

The following table summarizes the engineering characteristics for the baseline and each lamp replacement option in the 1000 

W HPS representative lamp type. 

Table 5.7.20 Engineering Summary for 1000 W HPS Representative Lamp Typef CSL Lamp Type Arc Tube Wattage

W

CCT

K

Initial Lumens

Initial Efficacy lm/W

Mean Lumens

Change in 

Mean 

Lumens 

From 

Baseline 

%

Mean Efficacy lm/W

Operating Orientation

Bulb Finish

Ballast Type

Ballast Efficiency

%

Lamp-and-Ballast System 

Power

W

Baseline HPS Ceramic 1000 2100 27,000 130.0 117,000 -- 117.0 Universal Clear HPS 

magnetic 91.8 1089

CSL 1 Modeled 

HPS Sapphire 958 2100 27,000 135.7 117,000 0.0 122.1 Universal Clear HPS magnetic 91.8 1043

 

As discussed in section 5.4, DOE notes that the increased efficacy lamp was modeled to have the same initial and mean lumen 

output as the baseline lamp. The increased efficacy is obtained by the modeled sapphire arc tube lamps requiring fewer watts to 

achieve the same light output.
5-34

5.7.6 100 W Mercury Vapor Representative Lamp Type 

The >2800 K and ≤4500 K, ≥50 W and ≤400 W representative equipment class contains 

five representative lamp types. In this section, DOE analyzes the 100 W MV representative lamp 

type for this equipment class. 

5.7.6.1 Baseline Models 

DOE selected baseline lamps as reference points from which DOE measured changes 

resulting from potential energy conservation standards. As discussed in section 5.2, a baseline 

lamp is typically the most common, least efficacious lamp sold in a given equipment class. To 

determine energy savings and changes in price, DOE compared each higher efficacy level with 

the baseline unit. 

DOE considered a number of criteria when selecting which commercially available lamp 

would serve as a baseline. First, as discussed in section 5.3.1, DOE selected a 100 W MV lamp 

as a baseline lamp because of its relatively high shipment volume. Then, DOE identified typical 

characteristics for these types of lamps (i.e., CRI, rated life, bulb shape, base type, and operating 

orientation).i Among all 100 W MV lamps within the representative equipment class that had the 

most common characteristics, DOE selected the least efficacious 100 W MV lamp as the 

baseline. Table 5.7.21 describes the characteristics of the 100 W MV baseline lamp. 

DOE also considered a MH baseline with similar characteristics, including mean lumen 

output, for the 100 W MV representative lamp type. This second baseline lamp was selected to 

account for the different high-volume lamps within the representative lamp type and their 

associated customer economics. Even though MV lamps are the least efficacious lamps in this 

equipment class, a large portion of the market has already transitioned from MV technology to 

MH technology. As described in section 5.3.1, the least-efficacious MH lamp with similar 

characteristics to the 100 W MV baseline was a 70 W pulse-start MH lamp, since there are no 

probe-start MH lamps at these low wattages. 

Table 5.7.21 Baseline Lamps for the 100 W MV Representative Lamp Type

CSL Lamp 

Type

Wattage 

W

CCT 

K

Initial 

Lumens

Initial 

Efficacy 

lm/W

Mean 

Lumens

Mean 

Efficacy 

lm/W

Operating 

Orientation

Baseline MV 100 3900 4000 40.0 2800 28.0 Universal

Baseline 

MH/CSL 2 Pulse MH 70 4000 5500 78.6 3000 42.9 Universal

5.7.6.2 Candidate Standard Levels and More Efficacious Substitutes 

As outlined in chapter 4 of the interim TSD, DOE identified several design options to 

improve the efficacy of MV and MH lamps. At the MV level, the only option DOE identified 

was a switch to a more efficacious technology, such as MH. At the MH level, the means to 

improve efficacy included switching from probe-start technology to pulse-start technology and 
5-35

from quartz arc tubes to ceramic arc tubes.kThese design options are the basis upon which DOE 

developed CSLs. Finally, DOE determined the maximum improvement in efficacy that was 

technologically feasible for HID lamps, as required by section 325(o) of EPCA. (42 U.S.C. 

6295(o)) 

Table 5.7.22 Summary of the CSLs for the 100 W MV Representative Lamp Type 

CSL Design Option Initial Efficacy Requirementj

CSL 1 N/A* lm/W = 45.5 * W0.10

Baseline MH/CSL 2 Pulse MH lm/W = 50.7 * W0.10

CSL 3 CMH lm/W = 48.7 * W0.13

*While no probe-start MH lamps were found in this representative lamp type, the CSL 1 

equation still applies at these lower wattages.

 

Figure 5.7.6 illustrates the three CSLs on a plot with the representative units for the 100 

W MV representative lamp type. The squares represent the representative units selected by DOE 

for each of the technologies in this representative lamp type, while the lines correspond to the 

three CSLs. 

Figure 5.7.6 Candidate Standard Levels for the 100 W MV Representative Lamp Type

 

k

 DOE notes that within this representative lamp type, no probe-start MH lamps were found. As such, none of the 

representative lamps are probe-start MH, but the CSL 1 equation that correlates to a switch from MV to probe-start 

MH still applies at these wattages. 

0

20

40

60

80

100

120

45 50 55 60 65 70 75 80 85 90 95 100 105

Initial Lamp Efficacy (lm/W)

Wattage

CSL 1

CSL 2

CSL 3

MV Baseline Representative Unit

Baseline MH/CSL 2 Representative Unit

CSL 3 Representative Unit
5-36

Table 5.7.23 Lamp Designs for the 100 W MV Representative Lamp Type 

CSL Lamp Type Wattage 

W

CCT 

K

Initial 

Lumens

Initial 

Efficacy 

lm/W

Mean 

Lumens

Mean 

Efficacy 

lm/W

Operating 

Orientation

Baseline MV 100 3900 4000 40.0 2800 28.0 Universal

CSL 1 N/A

Baseline 

MH/CSL 2 Pulse MH 70 4000 5500 78.6 3000 42.9 Universal

CSL 3 CMH 50 3000 4100 82.0 2750 55.0 Universal

5.7.6.3 Engineering Summary 

The following table summarizes the engineering characteristics for each lamp replacement option in the 100 W MV 

representative lamp type. 

Table 5.7.24 Engineering Summary for 100 W MV Representative Lamp Type CSL Lamp Type Starting Method Arc Tube Wattage

W

CCT

K

Initial Lumens

Initial Efficacy lm/W

Mean Lumens

Change in 

Mean 

Lumens 

From 

Baseline 

%

Mean Efficacy lm/W

Operating Orientation

Bulb Finish

Ballast Type

Ballast Efficiency

%

Lamp-and-Ballast 

System Power

W

Baseline MV N/A N/A 100 3900 4000 40.0 2800 -- 28.0 Universal Coated MV

magnetic 83.3 120

CSL 1 N/A

Baseline 

MH/CSL 2 MH Pulse Quartz 70 4000 5500 78.6 3000 +7.1 42.9 Universal Clear MHmagnetic 72.0 97

CSL 3 MH Pulse Ceramic 50 3000 4100 82.0 2750 -1.8 55.0 Universal Clear MH

electronic 89.3 56
5-37

5.7.7 175 W Mercury Vapor Representative Lamp Type 

The >2800 K and ≤4500 K, ≥50 W and ≤400 W representative equipment class contains 

five representative lamp types. In this section, DOE analyzes the 175 W MV representative lamp 

type for this equipment class. 

5.7.7.1 Baseline Models 

DOE selected baseline lamps as reference points from which DOE measured changes 

resulting from potential energy conservation standards. As discussed in section 5.2, a baseline 

lamp is typically the most common, least efficacious lamp sold in a given equipment class. To 

determine energy savings and changes in price, DOE compared each higher efficacy level with 

the baseline unit. 

DOE considered a number of criteria when selecting which commercially available lamp 

would serve as a baseline. First, as discussed in section 5.3.1, DOE selected a 175 W MV lamp 

as a baseline lamp because of its relatively high shipment volume. Then, DOE identified typical 

characteristics for these types of lamps (i.e., CRI, rated life, bulb shape, base type, and operating 

orientation).i Among all 175 W MV lamps within the representative equipment class that had the 

most common characteristics, DOE selected the least efficacious 175 W MV lamp as the 

baseline. Table 5.7.25 describes the characteristics of the 175 W MV baseline lamp. 

DOE also considered a MH baseline with similar characteristics, including mean lumen 

output, for the 175 W MV representative lamp type. This second baseline lamp was selected to 

account for the different high-volume lamps within the representative lamp type and their 

associated customer economics. Even though MV lamps are the least efficacious lamps in this 

equipment class, a large portion of the market has already switched from MV technology to MH 

technology. As described in section 5.3.1, the least efficacious MH lamp with similar 

characteristics to the 175 W MV baseline was a 100 W pulse-start MH lamp, since there are no 

probe-start MH lamps at these low wattages. 

Table 5.7.25 Baseline Lamps for the 100 W MV Representative Lamp Type 

CSL Lamp 

Type

Wattage 

W

CCT 

K

Initial 

Lumens

Initial 

Efficacy 

lm/W

Mean

Lumens

Mean 

Efficacy 

lm/W

Operating 

Orientation

Baseline MV 175 3900 7800 44.6 6630 37.9 Universal

Baseline 

MH/CSL 2 Pulse MH 100 4000 8100 81.0 5800 58.0 Universal

5.7.7.2 Candidate Standard Levels and More Efficacious Substitutes 

As outlined in chapter 4 of the interim TSD, DOE identified several design options to 

improve the efficacy of MV and MH lamps. At the MV level, the only option DOE identified 

was a switch to a more efficacious technology, such as MH. At the MH level, means to improve 

efficacy included switching from probe-start technology to pulse-start technology and from 
5-38

quartz arc tubes to ceramic arc tubes.lThese design options are the basis upon which DOE 

developed CSLs. Finally, DOE determined the maximum improvement in efficacy that was 

technologically feasible for HID lamps, as required by section 325(o) of EPCA. (42 U.S.C. 

6295(o)) 

Table 5.7.26 Summary of the CSLs for the 175 W MV Representative Lamp Type 

CSL Design Option Initial Efficacy Requirementj

CSL 1 N/A* lm/W = 45.5 * W0.10

Baseline MH/CSL 2 Pulse MH lm/W = 50.7 * W0.10

CSL 3 CMH lm/W = 48.7 * W0.13

*While no probe-start MH lamps were found in this representative lamp type, the CSL 

1 equation still applies at these lower wattages.

Figure 5.7.7 illustrates the three CSLs on a plot with the representative units for the 175 

W MV representative lamp type. The squares represent the representative units selected by DOE 

for each of the technologies in this representative lamp type, while the lines correspond to the 

three CSLs. 

Figure 5.7.7 Candidate Standard Levels for the 175 W MV Representative Lamp Type 

 

l

 DOE notes that within this representative lamp type, no probe-start MH lamps were found. As such, none of the 

representative lamps are probe-start MH, but the CSL 1 equation that correlates to a switch from MV to probe-start 

MH still applies at these wattages. 

0

20

40

60

80

100

120

55 70 85 100 115 130 145 160 175 190

Initial Lamp Efficacy (lm/W)

Wattage

CSL 1

CSL 2

CSL 3

Baseline MV Representative Unit

Baseline MH/CSL 2 Representative Unit

CSL 3 Representative Unit
5-39

Table 5.7.27 Lamp Designs for the 175 W MV Representative Lamp Type 

CSL Lamp Type Wattage 

W

CCT 

K

Initial 

Lumens

Initial 

Efficacy 

lm/W

Mean 

Lumens

Mean 

Efficacy 

lm/W

Operating 

Orientation

Baseline MV 175 3900 7800 44.6 6630 37.9 Universal

CSL 1 N/A

Baseline 

MH/CSL 2 Pulse-start MH 100 4000 8100 81.0 5800 58.0 Universal

CSL 3 CMH 70 3000 7200 102.9 5980 85.4 Universal

5.7.7.3 Engineering Summary 

The following table summarizes the engineering characteristics for each lamp replacement option in the 175 W MV 

representative lamp type. 

Table 5.7.28 Engineering Summary for 175 W MV Representative Lamp Type CSL Lamp Type Starting Method Arc Tube Wattage

W

CCT

K

Initial Lumens

Initial Efficacy lm/W

Mean Lumens

Change in 

Mean 

Lumens 

From 

Baseline 

%

Mean Efficacy lm/W

Operating Orientation

Bulb Finish

Ballast Type

Ballast Efficiency

%

Lamp-and-Ballast System 

Power

W

Baseline MV N/A N/A 175 3900 7800 44.6 6630 -- 37.9 Universal Coated MV

magnetic 85.4 205

CSL 1 N/A

Baseline 

MH/CSL 2 MH Pulse Quartz 100 4000 8100 81.0 5800 -12.5 58.0 Universal Clear MHmagnetic 76.9 130

CSL 3 MH Pulse Ceramic 70 3000 7200 102.9 5980 -9.8 85.4 Universal Clear MH

electronic 89.7 78
5-40

5.7.8 250 W Mercury Vapor Representative Lamp Type 

The >2800 K and ≤4500 K; ≥50 W and ≤400 W representative equipment class contains 

five representative lamp types. In this section, DOE analyzes the 250 W MV representative lamp 

type for this equipment class. 

5.7.8.1 Baseline Models 

DOE selected baseline lamps as reference points from which DOE measured changes 

resulting from potential energy conservation standards. As discussed in section 5.2, a baseline 

lamp is typically the most common, least efficacious lamp sold in a given equipment class. To 

determine energy savings and changes in price, DOE compared each higher efficacy level with 

the baseline unit. 

DOE considered a number of criteria when selecting which commercially available lamp 

would serve as a baseline. First, as discussed in section 5.3.1, DOE selected a 250 W MV lamp 

as a baseline lamp because of its relatively high shipment volume. Then, DOE identified typical 

characteristics for these types of lamps (i.e., CRI, rated life, bulb shape, base type, and operating 

orientation).i Among all 250 W MV lamps within the representative equipment class that had the 

most common characteristics, DOE selected the least efficacious 250 W MV lamp as the 

baseline. Table 5.7.29 describes the characteristics of the 250 W MV baseline lamp. 

DOE also considered a MH baseline with similar characteristics, including mean lumen 

output, for the 250 W MV representative lamp type. This second baseline lamp was selected to 

account for the different high-volume lamps within the representative lamp type and their 

associated customer economics. Even though MV lamps are the least efficacious lamps in this 

equipment class, a large portion of the market has already switched from MV technology to MH 

technology. As described in section 5.3.1, the least efficacious MH lamp with similar 

characteristics to the 250 W MV baseline was a 175 W probe-start MH lamp. 

Table 5.7.29 Baseline Lamps for the 250 W MV Representative Lamp Type 

CSL Lamp 

Type

Wattage 

W

CCT 

K

Initial 

Lumens

Initial 

Efficacy 

lm/W

Mean 

Lumens

Mean 

Efficacy 

lm/W

Operating 

Orientation

Baseline MV 250 4000 12,500 50.0 10,000 40.0 Universal

Baseline 

MH/CSL 1 Probe MH 175 4000 13,500 77.1 9100 52.0 Universal

5.7.8.2 Candidate Standard Levels and More Efficacious Substitutes 

As outlined in chapter 4 of the interim TSD, DOE identified several design options to 

improve the efficacy of MV and MH lamps. At the MV level, the only option DOE identified 

was a switch to a more efficacious technology, such as MH. At the MH level, means to improve 

efficacy included switching from probe-start technology to pulse-start technology and from 

quartz arc tubes to ceramic arc tubes. These design options are the basis upon which DOE 

developed CSLs. Finally, DOE determined the maximum improvement in efficacy that was 
5-41

technologically feasible for HID lamps, as required by section 325(o) of EPCA. (42 U.S.C. 

6295(o)) 

Table 5.7.30 Summary of the CSLs for the 250 W MV Representative Lamp Type 

CSL Design Option Initial Efficacy Requirementj

Baseline MH/CSL 1 Probe MH lm/W = 45.5 * W0.10

CSL 2 Pulse MH lm/W = 50.7 * W0.10

CSL 3 CMH lm/W = 48.7 * W0.13

 

Figure 5.7.8 illustrates the three CSLs on a plot with the representative units for the 250 

W MV representative lamp type. The squares represent the representative units selected by DOE 

for each of the four technologies in this representative lamp type, while the lines correspond to 

the three CSLs. 

Figure 5.7.8 Candidate Standard Levels for the 250 W MV Representative Lamp Type

0

20

40

60

80

100

120

75 100 125 150 175 200 225 250 275

Initial Lamp Efficacy (lm/W)

Wattage

CSL 1

CSL 2

CSL 3

MV Baseline Representative Unit

Baseline MH/CSL 1 Representative Unit

CSL 2 Representative Unit

CSL 3 Representative Unit
5-42

Table 5.7.31 Lamp Designs for the 250 W MV Representative Lamp Type 

CSL Lamp Type Wattage 

W

CCT 

K

Initial 

Lumens

Initial 

Efficacy 

lm/W

Mean 

Lumens

Mean 

Efficacy 

lm/W

Operating 

Orientation

Baseline MV 250 4000 12,500 50.0 10,000 40.0 Universal

Baseline MH/CSL 1 Probe MH 175 4000 13,500 77.1 9100 52.0 Universal

CSL 2 Pulse MH 150 3400 13,300 88.7 10,000 66.7 Universal

CSL 3 CMH 100 3000 9500 95.0 7600 76.0 Universal

5.7.8.3 Engineering Summary 

The following table summarizes the engineering characteristics for each lamp replacement option in the 250 W MV 

representative lamp type. At CSL 3, a lamp was not commercially available that maintained mean lumens within 10 percent. While 

DOE sought to maintain higher efficacy substitutes within 10 percent, it also sought to analyze commercially available lamps. 

Table 5.7.32 Engineering Summary for 250 W MV Representative Lamp Type CSL Lamp Type Starting Method Arc Tube Wattage

W

CCT

K

Initial Lumens

Initial Efficacy lm/W

Mean Lumens

Change in 

Mean 

Lumens 

From 

Baseline 

%

Mean Efficacy lm/W

Operating Orientation

Bulb Finish

Ballast Type

Ballast Efficiency

%

Lamp-and-Ballast 

System Power

W

Baseline MV N/A N/A 250 4000 12,500 50.0 10,000 -- 40.0 Universal Coated MV 

magnetic 87.4 286

Baseline 

MH/CSL 1 MH Probe Quartz 175 4000 13,500 77.1 9100 -9.0 52.0 Universal Clear MH magnetic 88.0 199

CSL 2 MH Pulse Quartz 150 3400 13,300 88.7 10,000 0.0 66.7 Universal Clear MH 

magnetic 81.0 185

CSL 3 MH Pulse Ceramic 100 3000 9500 95.0 7600 -24.0 76.0 Universal Clear MH 

electronic 90.1 111
5-43

5.7.9 400 W Mercury Vapor Representative Lamp Type 

The >2800 K and ≤4500 K; ≥50 W and ≤400 W representative equipment class contains 

five representative lamp types. In this section, DOE analyzes the 400 W MV representative lamp 

type for this equipment class. 

5.7.9.1 Baseline Models 

DOE selected baseline lamps as reference points from which DOE measured changes 

resulting from potential energy conservation standards. As discussed in section 5.2, a baseline 

lamp is typically the most common, least efficacious lamp sold in a given equipment class. To 

determine energy savings and changes in price, DOE compared each higher efficacy level with 

the baseline unit. 

DOE considered a number of criteria when selecting which commercially available lamp 

would serve as a baseline. First, as discussed in section 5.3.1, DOE selected a 400 W MV lamp 

as a baseline lamp because of its relatively high shipment volume. Then, DOE identified typical 

characteristics these types of lamps (i.e., CRI, rated life, bulb shape, base type, and operating 

orientation).i Among all 400 W MV lamps within the representative equipment class that had 

these common characteristics, DOE selected the least efficacious 400 W MV lamp as a baseline. 

Table 5.7.33 describes the characteristics of the 400 W MV baseline lamp. 

DOE also considered a MH baseline with similar characteristics, including mean lumen 

output, for the 400 W MV representative lamp type. This second baseline lamp was selected to 

account for the different high-volume lamps within the representative lamp type and their 

associated customer economics. Even though MV lamps are the least efficacious lamps in this 

equipment class, a large portion of the market has already switched from MV technology to MH 

technology. As described in section 5.3.1, the least efficacious MH lamp with similar 

characteristics to the 400 W MV baseline was a 250 W probe-start MH lamp. 

Table 5.7.33 Baseline Lamps for the 400 W MV Representative Lamp Type 

CSL Lamp 

Type

Wattage

W

CCT 

K

Initial 

Lumens

Initial 

Efficacy 

lm/W

Mean 

Lumens

Mean 

Efficacy 

lm/W

Operating 

Orientation

Baseline MV 400 4000 22,000 55.0 16,200 40.5 Universal

Baseline 

MH/CSL 1 Probe MH 250 4200 22,000 88.0 15,000 60.0 Universal

5.7.9.2 Candidate Standard Levels and More Efficacious Substitutes 

As outlined in chapter 4 of the interim TSD, DOE identified several design options to 

improve the efficacy of MV and MH lamps. At the MV level, the only option DOE identified 

was a switch to a more efficacious technology, such as MH. At the MH level, means to improve 

efficacy included switching from probe-start technology to pulse-start technology and from 

quartz arc tubes to ceramic arc tubes. These design options are the basis upon which DOE 

developed CSLs. Finally, DOE determined the maximum improvement in efficacy that was 
5-44

technologically feasible for HID lamps, as required by section 325(o) of EPCA. (42 U.S.C. 

6295(o)) 

Table 5.7.34 Summary of the CSLs for the 400 W MV Representative Lamp Type 

CSL Design Option Initial Efficacy Requirementj

Baseline MH/CSL 1 Probe MH lm/W = 45.5 * W0.10

CSL 2 Pulse MH lm/W = 50.7 * W0.10

CSL 3 CMH lm/W = 48.7 * W0.13

Figure 5.7.9 illustrates the three CSLs on a plot with the representative units for the 400 

W MV representative lamp type. The squares represent the representative units selected by DOE 

for each of the four technologies in this representative lamp type, while the lines correspond to 

the three CSLs. 

Figure 5.7.9 Candidate Standard Levels for the 400 W MV Representative Lamp Type 

0

20

40

60

80

100

120

125 150 175 200 225 250 275 300 325 350 375 400 425

Initial Lamp Efficacy (lm/W)

Wattage

CSL 1

CSL 2

CSL 3

MV Baseline Representative Unit

Baseline MH/CSL 1 Representative Unit

CSL 2 Representative Unit

CSL 3 Representative Unit
5-45

Table 5.7.35 Lamp Designs for the 400 W MV Representative Lamp Type 

CSL Lamp Type Wattage 

W

CCT K

Initial 

Lumens

Initial 

Efficacy 

lm/W

Mean 

Lumens

Mean 

Efficacy 

lm/W

Operating 

Orientation

Baseline MV 400 4000 22,000 55.0 16,200 40.5 Universal

Baseline MH/CSL 1 Probe MH 250 4200 22,000 88.0 15,000 60.0 Universal

CSL 2 Pulse MH 200 4000 19,000 95.0 16,340 81.7 Horizontal

CSL 3 CMH 150 3000 15,000 100.0 12,450 83.0 Universal

5.7.9.3 Engineering Summary 

The following table summarizes the engineering characteristics for each lamp replacement option in the 400 W MV 

representative lamp type. At CSL 3, a lamp was not commercially available that maintained mean lumens within 10 percent. While 

DOE sought to maintain higher efficacy substitutes within 10 percent, it also sought to analyze commercially available lamps. 

Table 5.7.36 Engineering Summary for 400 W MV Representative Lamp Type CSL Lamp Type Starting Method Arc Tube Wattage

W

CCT

K

Initial Lumens

Initial Efficacy lm/W

Mean Lumens

Change in 

Mean 

Lumens 

From 

Baseline 

%

Mean Efficacy lm/W

Operating Orientation

Bulb Finish

Ballast Type

Ballast Efficiency

%

Lamp-and-Ballast System 

Power

W

Baseline MV N/A N/A 400 4000 22000 55.0 16,200 -- 40.5 Universal Coated MV 

magnetic 89.1 449

Baseline 

MH/CSL 1 MH Probe Quartz 250 4200 22000 88.0 15,000 -7.4 60.0 Universal Clear MH magnetic 88.0 284

CSL 2 MH Pulse Quartz 200 4000 19000 95.0 16,340 +0.9 81.7 Horizontal Clear MH 

magnetic 88.0 227

CSL 3 MH Pulse Ceramic 150 3000 15000 100.0 12,450 -23.1 83.0 Universal Clear MH 

electronic 90.4 166
5-46

5.7.10 400 W Metal Halide Representative Lamp Type 

The >2800 K and ≤4500 K; ≥50 W and ≤400 W representative equipment class contains 

five representative lamp types. In this section, DOE analyzes the 400 W MH representative lamp 

type for this equipment class. 

5.7.10.1 Baseline Models 

DOE selected baseline lamps as reference points from which DOE measured changes 

resulting from potential energy conservation standards. As discussed in section 5.2, a baseline 

lamp is typically the most common, least efficacious lamp sold in a given equipment class. To 

determine energy savings and changes in price, DOE compared each higher efficacy level with 

the baseline unit. 

DOE considered a number of criteria when selecting which commercially available lamp 

would serve as a baseline lamp. First, as discussed in section 5.3.1, DOE selected a 400 W MH 

lamp as a baseline lamp because of its relatively high shipment volume. Then, DOE identified 

typical characteristics for these types of lamps (i.e., CRI, rated life, bulb shape, base type, and 

operating orientation).i Unlike the other four representative lamp types in this equipment class, 

DOE only included one baseline lamp. A 400 W MH baseline lamp did not match any of the 

lumen packages of a MV baseline, but because of its high shipment volume, a 400 W MH 

baseline was analyzed. Among all 400 W MH lamps within the representative equipment class 

that had the most common characteristics, DOE selected the least efficacious 400 W MH lamp as 

the baseline. Table 5.7.37 describes the characteristics of the 400 W MH baseline lamp. 

Table 5.7.37 Baseline Lamps for the 400 W MH Representative Lamp Type 

CSL Lamp 

Type

Wattage 

W

CCT 

K

Initial 

Lumens

Initial 

Efficacy 

lm/W

Mean 

Lumens

Mean 

Efficacy 

lm/W

Operating 

Orientation

Baseline/

CSL 1

Probe 

MH 400 4000 36,000 90.0 22,100 55.3 Universal

5.7.10.2 Candidate Standard Levels and More Efficacious Substitutes 

As outlined in chapter 4 of the interim TSD, DOE identified several design options to 

improve the efficacy of probe-start MH lamps. These design options are the basis upon which 

DOE developed CSLs and included switching from probe-start technology to pulse-start 

technology and from quartz arc tubes to ceramic arc tubes. Finally, DOE determined the 

maximum improvement in efficacy that is technologically feasible for HID lamps, as required by 

section 325(o) of EPCA. (42 U.S.C. 6295 (o)) 
5-47

Table 5.7.38 Summary of the CSLs for the 400 W MH Representative Lamp Type 

CSL Design Option Initial Efficacy Requirementj

Baseline/CSL 1 Probe MH lm/W = 45.5 * W0.10

CSL 2 Pulse MH lm/W = 50.7 * W0.10

CSL 3 CMH lm/W = 48.7 * W0.13

 

Figure 5.7.10 illustrates the three CSLs on a plot with the representative units for the 400 

W MH representative lamp type. The squares represent the representative units selected by DOE 

for each of the three technologies in this representative lamp type, while the lines correspond to 

the three CSLs. 

Figure 5.7.10 Candidate Standard Levels for the 400 W MH Representative Lamp Type 

0

20

40

60

80

100

120

225 250 275 300 325 350 375 400 425

Initial Lamp Efficacy (lm/W)

Wattage

CSL 1

CSL 2

CSL 3

Baseline/CSL 1 Representative Unit

CSL 2 Representative Unit

CSL 3 Representative Unit
5-48

Table 5.7.39 Lamp Designs for the 400 W MH Representative Lamp Type 

CSL Lamp Type Wattage 

W

CCT 

K

Initial 

Lumens

Initial 

Efficacy 

lm/W

Mean 

Lumens

Mean 

Efficacy 

lm/W

Operating 

Orientation

Baseline N/A

Baseline/CSL 1 Probe MH 400 4000 36,000 90.0 22,100 55.3 Universal

CSL 2 Pulse MH 320 4300 30,000 93.8 21,000 65.6 Universal

CSL 3 CMH 250 3000 25,000 100.0 20,000 80.0 Universal

5.7.10.3 Engineering Summary 

The following table summarizes the engineering characteristics for each lamp replacement option in the 400 W MH 

representative lamp type. 

Table 5.7.40 Engineering Summary for 400 W MH Representative Lamp Type CSL Lamp Type Starting Method Arc Tube Wattage

W

CCT

K

Initial Lumens

Initial Efficacy lm/W

Mean Lumens

Change in 

Mean 

Lumens 

From 

Baseline 

%

Mean Efficacy lm/W

Operating Orientation

Bulb Finish

Ballast Type

Ballast Efficiency

%

Lamp-and-Ballast System 

Power

W

Baseline N/A

Baseline/CSL 1 MH Probe Quartz 400 4000 36,000 90.0 22,100 -- 55.3 Universal Clear MH 

magnetic 88.0 455

CSL 2 MH Pulse Quartz 320 4300 30,000 93.8 21,000 -5.0 65.6 Universal Clear MH 

magnetic 88.0 364

CSL 3 MH Pulse Ceramic 250 3000 25,000 100.0 20,000 -9.5 80.0 Universal Clear MH 

electronic 92.5 270
5-49

5.7.11 1000 W Mercury Vapor Representative Lamp Type 

The >2800 K and ≤4500 K; >400 W and ≤1000 W representative equipment class 

contains two representative lamp types. In this section, DOE analyzes the 1000 W MV 

representative lamp type for this equipment class. 

5.7.11.1 Baseline Models 

DOE selected baseline lamps as reference points from which DOE measured changes 

resulting from potential energy conservation standards. As discussed in section 5.2, a baseline 

lamp is typically the most common, least efficacious lamp sold in a given equipment class. To 

determine energy savings and changes in price, DOE compared each higher efficacy level with 

the baseline unit. 

DOE considered a number of criteria when selecting which commercially available lamp 

would serve as a baseline. First, as discussed in section 5.3.1, DOE selected a 1000 W MV lamp 

as a baseline lamp because of its relatively high shipment volume. Then, DOE identified typical 

characteristics for these types of lamps (i.e., CRI, rated life, bulb shape, base type, and operating 

orientation).i Among all 1000 W MV lamps within the representative equipment class that had 

the most common characteristics, DOE selected the least efficacious 1000 W MV lamp as the 

baseline. Table 5.7.41 describes the characteristics of the 1000 W MV baseline lamp. 

Table 5.7.41 Baseline Lamps for the 1000 W MV Representative Lamp Type 

CSL Lamp 

Type

Wattage 

W

CCT 

K

Initial 

Lumens

Initial 

Efficacy 

lm/W

Mean 

Lumens

Mean 

Efficacy 

lm/W

Operating 

Orientation

Baseline MV 1000 3600 59000 59.0 54,000 54.0 Universal

5.7.11.2 Candidate Standard Levels and More Efficacious Substitutes 

As outlined in chapter 4 of the interim TSD, DOE identified several design options to 

improve the efficacy of MV and MH lamps. At the MV level, the only option DOE identified 

was a switch to a more efficacious technology, such as MH. At the MH level, the only means to 

improve efficacy was to switch from probe-start technology to pulse-start technology.m

These 

design options are the basis upon which DOE developed CSLs. Finally, DOE determined the 

maximum improvement in efficacy that was technologically feasible for HID lamps, as required 

by section 325(o) of EPCA. (42 U.S.C. 6295 (o)) 

 

m

 While DOE did not find a probe-start MH lamp that fit into this representative lamp type, the CSL 1 equation still 

applies to any potential lamps, probe-start MH or other, in this equipment class. 
5-50

Table 5.7.42 Summary of the CSLs for the 1000 W MV Representative Lamp Type 

CSL Design Option Initial Efficacy Requirementj

CSL 1 N/A* lm/W = 0.021 * W + 74.3

CSL 2 Pulse MH lm/W = 0.021 * W + 83.8

*DOE did not find any probe-start MH lamps to fit this representative lamp type, but the CSL 

1 equation that relates to probe-start MH lamps still applies to the equipment class. 

 

Figure 5.7.11 illustrates the three CSLs on a plot with the representative units for the 

1000 W MV representative lamp type. The squares represent the representative units selected by 

DOE for each of the two technologies in this representative lamp type, while the lines correspond 

to the two CSLs. 

Figure 5.7.11 Candidate Standard Levels for the 1000 W MV Representative Lamp Type 

0

20

40

60

80

100

120

400 450 500 550 600 650 700 750 800 850 900 950 1000 1050

Iniitial Lamp Efficacy (lm/W)

Wattage (W)

CSL 1

CSL 2

Baseline Representative Unit

CSL 2 Representative Unit
5-51

Table 5.7.43 Lamp Designs for the 1000 W MV Representative Lamp Type

CSL Lamp 

Type

Wattage 

W

CCT 

K

Initial 

Lumens

Initial 

Efficacy 

lm/W

Mean 

Lumens

Mean 

Efficacy 

lm/W

Operating 

Orientation

Baseline MV 1000 3600 59,000 59.0 54,000 54.0 Universal

CSL 1 N/A

CSL 2 Pulse MH 750 4000 75,000 100.0 55,000 73.3 Base Up

5.7.11.3 Engineering Summary 

The following table summarizes the engineering characteristics for each lamp replacement option in the 1000 W MV 

representative lamp type. 

Table 5.7.44 Engineering Summary for 1000 W MV Representative Lamp Type CSL Lamp Type Starting Method Arc Tube Wattage

W

CCT

K

Initial Lumens

Initial Efficacy lm/W

Mean Lumens

Change in 

Mean 

Lumens 

From 

Baseline 

%

Mean Efficacy lm/W

Operating Orientation

Bulb Finish

Ballast Type

Ballast Efficiency

%

Lamp-and-Ballast System 

Power

W

Baseline MV N/A N/A 1000 3600 59,000 59.0 54,000 -- 54.0 Universal Coated MV 

magnetic 92.4 1083

CSL 1 N/A

CSL 2 MH Pulse Quartz 750 4000 75,000 100.0 55,000 +1.9 73.3 Base Up Clear MH 

magnetic 90.7 827
5-52

5.7.12 1000 W Metal Halide Representative Lamp Type 

The >2800 K and ≤4500 K; >400 W and ≤1000 W representative equipment class 

contains two representative lamp types. In this section, DOE analyzes the 1000 W MH 

representative lamp type for this equipment class. 

5.7.12.1 Baseline Models 

DOE selected baseline lamps as reference points from which DOE measured changes 

resulting from potential energy conservation standards. As discussed in section 5.2, a baseline 

lamp is typically the most common, least efficacious lamp sold in a given equipment class. To 

determine energy savings and changes in price, DOE compared each higher efficacy level with 

the baseline unit. 

DOE considered a number of criteria when selecting which commercially available lamp 

would serve as a baseline. First, as discussed in section 5.3.1, DOE selected a 1000 W MH lamp 

as a baseline lamp because of its relatively high shipment volume. Then, DOE identified typical 

characteristics for these types of lamps (i.e., CRI, rated life, bulb shape, base type, and operating 

orientation).i Among all 1000 W MH lamps within the representative equipment class that had 

the most common characteristics, DOE selected the least efficacious 1000 W MH lamp as the 

baseline. Table 5.7.45 describes the characteristics of the 1000 W MH baseline lamp. 

Table 5.7.45 Baseline Lamps for the 1000 W MH Representative Lamp Type 

CSL Lamp 

Type

Wattage 

W

CCT

K

Initial 

Lumens

Initial 

Efficacy 

lm/W

Mean 

Lumens

Mean 

Efficacy 

lm/W

Operating 

Orientation

Baseline Probe MH 1000 4200 105,000 105.0 84,000 84.0 Universal

5.7.12.2 Candidate Standard Levels and More Efficacious Substitutes 

As outlined in chapter 4 of the interim TSD, DOE identified several design options to 

improve the efficacy of MH lamps. The only means to improve efficacy for this representative 

lamp type was to switch from probe-start technology to pulse-start technology. These design 

options are the basis upon which DOE developed CSLs. Finally, DOE determined the maximum 

improvement in efficacy that was technologically feasible for HID lamps, as required by section 

325(o) of EPCA (42 U.S.C. 6295 (o)) 

Table 5.7.46 Summary of the CSLs for the 1000 W MH Representative Lamp Type 

CSL Design Option Initial Efficacy Requirementj

Baseline/CSL 1 Probe MH N/A

CSL 2 Pulse MH lm/W = 0.021 * W + 83.8

 

Figure 5.7.12 illustrates the three CSLs on a plot of the 1000 W MH representative lamp 

type. The squares represent the representative units selected by DOE for each of the two 

technologies in this representative lamp type, while the lines correspond to the two CSLs. 
5-53

Figure 5.7.12 Candidate Standard Levels for the 1000 W MH Representative Lamp Type 

0

20

40

60

80

100

120

400 450 500 550 600 650 700 750 800 850 900 950 1000 1050

Iniitial Lamp Efficacy (lm/W)

Wattage (W)

CSL 1

CSL 2

Baseline/CSL 1 Representative Unit

CSL 2 Representative Unit
5-54

Table 5.7.47 Lamp Designs for the 1000 W MV Representative Lamp Type 

CSL Lamp Type Wattage 

W

CCT 

K

Initial 

Lumens

Initial 

Efficacy 

lm/W

Mean 

Lumens

Mean 

Efficacy 

lm/W

Operating 

Orientation

Baseline N/A

Baseline/CSL 1 Probe MH 1000 4200 105,000 105.0 84,000 84.0 Universal

CSL 2 Pulse MH 875 4000 96,000 109.7 82,500 94.3 Universal

5.7.12.3 Engineering Summary 

The following table summarizes the engineering characteristics for each lamp replacement option in the 1000 W MH 

representative lamp type. 

Table 5.7.48 Engineering Summary for 1000 W MH Representative Lamp Type CSL Lamp Type Starting Method Arc Tube Wattage

W

CCT

K

Initial Lumens

Initial Efficacy lm/W

Mean Lumens

Change in 

Mean 

Lumens 

From 

Baseline 

%

Mean Efficacy lm/W

Operating Orientation

Bulb Finish

Ballast Type

Ballast Efficiency

%

Lamp-and-Ballast

System Power

W

Baseline N/A

Baseline/

CSL 1 MH Probe Quartz 1000 4200 105,000 105.0 84,000 -- 84.0 Universal Clear MH magnetic 91.8 1089

CSL 2 MH Pulse Quartz 875 4000 96,000 109.7 82,500 -1.8 94.3 Universal Clear MH 

magnetic 90.2 970
5-55

5.7.13 2000 W Metal Halide Representative Lamp Type 

The >2800 K and ≤4500 K; >1000 W and ≤2000 W representative equipment class 

contains one representative lamp type. In this section, DOE analyzes the 2000 W MH 

representative lamp type. 

5.7.13.1 Baseline Models 

DOE selected baseline lamps as reference points from which DOE measured changes 

resulting from potential energy conservation standards. As discussed in section 5.2, a baseline 

lamp is typically the most common, least efficacious lamp sold in a given equipment class. To 

determine energy savings and changes in price, DOE compared each higher efficacy level with 

the baseline unit. 

DOE considered a number of criteria when selecting which commercially available lamp 

would serve as a baseline. First, as discussed in section 5.3.1, DOE selected a 2000 W MH lamp 

as a baseline lamp because of its relatively high shipment volume. Then, DOE identified typical 

characteristics for these types of lamps (i.e., CRI, rated life, bulb shape, base type, and operating 

orientation).i Among all 2000 W MH lamps within the representative equipment class that had 

the most common characteristics, DOE selected the least efficacious 2000 W MH lamp as the 

baseline. Table 5.7.49 describes the characteristics of the 2000 W MH baseline lamp. 

Table 5.7.49 Baseline Lamp for the 2000 W MH Representative Lamp Type

CSL Lamp 

Type

Wattage 

W

CCT 

K

Initial 

Lumens

Initial 

Efficacy 

lm/W

Mean 

Lumens

Mean 

Efficacy 

lm/W

Operating 

Orientation

Baseline Probe MH 2000 4000 170,000 85.0 153,000 76.5 Universal

5.7.13.2 Candidate Standard Levels and More Efficacious Substitutes 

DOE identified more efficacious probe-start MH lamps as potential replacements for the 

2000 W MH baseline. These more efficacious probe-start MH lamps are the basis upon which 

DOE developed CSLs. DOE also determined that these more efficacious probe-start MH lamps 

are the maximum improvement in efficacy that is technologically feasible, as required by section 

325(o) of EPCA (42 U.S.C. 6295(o)) 

 This equipment class does not contain MV lamps because this rulemaking is only 

considering standards for MV lamps up to 1000 W. Additionally, DOE found no commercially 

available pulse-start MH or CMH lamps in this equipment class. As such, CSL 1 corresponds to 

a more efficacious probe-start MH lamp compared to the baseline probe-start MH lamp model. 

Table 5.7.50 Summary of the CSL for the 1000 W MV Representative Lamp Type 

CSL Design Option Initial Efficacy Requirementj

CSL 1 Probe MH lm/W = 95.3

 
5-56

Figure 5.7.13 illustrates the CSL on a plot with the representative units for the 2000 W 

MH representative lamp type. The squares represent the representative units selected by DOE for 

each of the two technologies in this representative lamp type, while the line corresponds to the 

CSL. 

Figure 5.7.13 Candidate Standard Level for the 2000 W MH Representative Lamp Type 

80

85

90

95

100

105

1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000

Initial Lamp Efficacy (lm/W)

Wattage (W)

CSL 1

Baseline Representative Unit

CSL 1 Representative Unit
5-57

Table 5.7.51 Lamp Designs for the 2000 W MV Representative Lamp Type 

CSL Lamp Type Wattage 

W

CCT 

K

Initial 

Lumens

Initial 

Efficacy 

lm/W

Mean 

Lumens

Mean 

Efficacy 

lm/W

Operating 

Orientation

Baseline Probe MH 2000 4000 170,000 85.0 153,000 76.5 Horizontal

CSL 1 Probe MH 1500 3700 155,000 103.3 140,000 93.3 Universal

5.7.13.3 Engineering Summary 

The following table summarizes the engineering characteristics for each lamp replacement option in the 2000 W MH 

representative lamp type. 

Table 5.7.52 Engineering Summary for 2000 W MH Representative Lamp Type CSL Lamp Type Starting Method Arc Tube Wattage

W

CCT

K

Initial Lumens

Initial Efficacy lm/W

Mean Lumens

Change in 

Mean 

Lumens 

From 

Baseline 

%

Mean Efficacy lm/W

Operating Orientation

Bulb Finish

Ballast Type

Ballast Efficiency

%

Lamp-and-Ballast 

System Power

W

Baseline MH Probe Quartz 2000 4000 170,000 85.0 153,000 -- 76.5 Horizontal Clear MH 

magnetic 95.0 2105

CSL 1 MH Probe Quartz 1500 3700 155,000 103.3 140,000 -8.5 93.3 Universal Clear MH 

magnetic 91.9 1632
5-58

5.7.14 Summary of Representative Lamp Type Candidate Standard Levels

The figures below depict the CSL equations for each representative equipment class on a 

plot of the representative lamp models selected. 

Figure 5.7.14 ≥1900 K and ≤2800 K Representative Equipment Class 

80

90

100

110

120

130

140

0 200 400 600 800 1000

Initial Lamp Efficacy (lm/W)

Lamp Wattage (W)

CSL 1

Baseline Representative Units

CSL 1 Representative Units
5-59

Figure 5.7.15 >2800 K and ≤4500 K, ≥50 W and ≤400 W Representative Equipment Class 

Figure 5.7.16 >2800 K and ≤4500 K, >400 W and ≤1000 W Representative Equipment 

Class 

0

20

40

60

80

100

120

25 50 75 100 125 150 175 200 225 250 275 300 325 350 375 400

Initial Lamp Efficacy (lm/W)

Wattage

CSL 1

CSL 2

CSL 3

Baseline Representative Units

CSL 1 Representative Units

CSL 2 Representative Units

CSL 3 Representative Units

0

20

40

60

80

100

120

400 450 500 550 600 650 700 750 800 850 900 950 1000

Iniitial Lamp Efficacy (lm/W)

Wattage (W)

CSL 1

CSL 2

Baseline Representative Units

CSL 1 Representative Units

CSL 2 Representative Units
5-60

Figure 5.7.17 >2800 K and ≤4500 K, >1000 W and ≤2000 W Representative Equipment 

Class 

5.8 SCALING TO EQUIPMENT CLASSES NOT ANALYZED 

DOE identified and selected certain equipment classes as “representative” equipment 

classes on which to concentrate its analytical effort. DOE chose these representative equipment 

classes primarily due to their high market volumes. To scale CSLs to equipment classes not 

directly analyzed, DOE focused its analytical efforts on data reported by manufacturers in their 

publically-available HID lamp catalogs for lamps. 

To develop relationships between clear and coated bulb finish, enclosed-rated and openrated luminaire characteristic, and >2800 K to ≤4500 K and >4500 K to <7000 K CCT, DOE 

identified pairs of lamps in which the only difference between the lamps was the parameter 

under consideration for scaling. For example, to identify the scaling factor between clear lamps 

and coated lamps, DOE identified pairs of lamps within two equipment classes that were 

manufactured by the same manufacturer, within the same family, and differed only by bulb 

finish. DOE calculated the average percentage change in initial efficacy for each of these pairs. 

These averages are used to directly calculate the scaling factors. Additionally, based on data 

analysis and manufacturer interviews, DOE concluded that each of these scaling characteristics 

are independent and do not influence each other. Thus, in order to obtain the efficacy 

requirement for an equipment class with coated, open-rated lamps, the equation for comparable 

clear, enclosed-rated lamps would be simply multiplied by both the bulb finish and luminaire 

characteristic scaling factors. 

80

85

90

95

100

105

1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000

Initial Lamp Efficacy (lm/W)

Wattage (W)

CSL 1

Baseline Representative Unit

CSL 1 Representative Unit
5-61

5.8.1 Bulb Finish 

As discussed in chapter 3 of the interim TSD, manufacturers offer HID lamps in either 

clear or coated bulb finishes. The coating on a lamp blocks a portion of the light produced by the 

arc tube from leaving the lamp. Thus, coated lamps have lower efficacy than their clear 

counterparts. By comparing pairs of coated and clear lamps, all other features remaining 

approximately the same, DOE concluded that coating on MH and HPS lamps reduced overall 

lamp efficacy. For MV lamps, DOE determined that coated lamps were more efficacious than 

their clear counterparts because MV lamps generate a large amount of ultraviolet (UV) light and 

the coating on MV lamps converts the UV light into visible light, thereby increasing the efficacy 

of the lamp.n

 The scaling factors determined for the bulb finish for the two different CCT ranges 

differed significantly enough to warrant separate scaling factors for those equipment classes. For 

both of these bulb finish scaling factors, DOE found no correlation between wattage and efficacy 

difference and thus kept one constant scaling factor for those characteristics. As explained in 

chapter 3 of the interim TSD, DOE classified MV lamps into the clear equipment classes 

regardless of actual bulb finish, and thus MV lamps were not used to determine bulb finish 

scaling factors. DOE found that in the ≥1900 K and ≤2800 K, ≥50 W and ≤1000 W 

representative equipment class, coated lamps were on average 7.9 percent less efficacious than 

clear lamps. Thus, the equations for the ≥1900 K and ≤2800 K, ≥50 W and ≤1000 W, clear 

equipment classes were multiplied by a scaling factor of 0.921 to obtain the equations for the 

≥1900 K and ≤2800 K, ≥50 W and ≤1000 W, coated equipment classes.o DOE found that in the 

three >2800 K and ≤4500 K representative equipment classes, coated MH lamps were on 

average 5.4 percent less efficacious than clear MH lamps. Therefore, the equations for the >2800 

K and ≤4500 K clear equipment classes were multiplied by a scaling factor of 0.946 to obtain the 

equations for the >2800 K and ≤4500 K coated equipment classes. These scaling factors are 

summarized in Table 5.8.1.

5.8.2 Luminaire Characteristic 

As discussed in chapter 3 of the interim TSD, DOE found that MH lamps can be offered 

as either open-rated or enclosed-rated. One of the requirements for a MH lamp to be labeled as 

open-rated is having a glass shroud that surrounds the arc tube to protect the environment and 

any occupants around the lamp in the event of arc tube rupture. After analyzing data and 

interviewing manufacturers, DOE concluded that this glass shroud on MH lamps reduces overall 

lamp efficacy by reducing light transmittance. 

 

n

 Clear and coated finishes are offered for MV lamps. However, the coated MV lamps are only offered in the >2800 

K and ≤4500 K classes, and clear MV lamps are only offered in the >4500 K and <7000 K classes. DOE chose to 

include MV lamps in the clear equipment classes, regardless of the actual bulb finish. See chapter 3 of the interim 

TSD for further details. 

o

 In the ≥1900 K and ≤2800 K; ≥50 W and ≤1000 W; coated; enclosed equipment class, DOE found only one CMH 

lamp, with the rest being HPS lamps. The scaling factor calculated with HPS lamp data ≥1900 K and ≤2800 K will 

be used to calculate the efficacy requirement in the ≥1900 K and ≤2800 K; ≥50 W and ≤1000 W; coated; enclosed 

equipment class. In the ≥1900 K and ≤2800 K; ≥50 W and ≤1000 W; open equipment classes, the only lamps 

available are MH because DOE defined all HPS lamps as enclosed-rated. For that reason, the scaling factors 

calculated with MH lamp data >2800 K and ≤4500 K will be used to calculate the efficacy requirement in the ≥1900 

K and ≤2800 K; ≥50 W and ≤1000 W; open equipment classes. 
5-62

Similar to the bulb finish scaling factor, DOE found no correlation between lamp wattage 

or efficacy and scaling factor. DOE found that in the >2800 K and ≤4500 K CCT representative 

equipment classes, open-rated lamps were on average 4.5 percent less efficacious than clear 

lamps. Therefore, the equations for >2800 K and ≤4500 K, enclosed-rated equipment classes 

were multiplied by a scaling factor of 0.955 to obtain the equations for the >2800 K and ≤4500 

K, open-rated equipment classes. This scaling factor is shown in Table 5.8.1.

5.8.3 CCT Range 

 As discussed in chapter 3 of the interim TSD, within the three CCT ranges DOE used to 

separate equipment classes, MH and MV lamps are found within the 2800 K and 4500 K, and 

4500 K and 7000 K rangesp. However, DOE found that the >2800 K to ≤4500 K CCT lamps 

are much more common, having over ten times as many listings in manufacturer catalogs 

compared to the lamps in the >4500 K and <7000 K range. Thus, the 2800 K and 4500 K 

range was regarded as representative, and DOE focused its analytical efforts on these lamps, 

choosing to scale to the >4500 K and <7000 K range. 

 DOE identified the pairs of lamps from the same manufacturer and lamp families that 

only differed by these CCT ranges. DOE found the data exhibited some variation across lamp 

wattage but the overall trend was inconclusive; therefore, DOE again calculated an average 

scaling factor to be applied at all wattages when going from the lower CCT range to the higher 

CCT range. DOE found that on average the lamps in the >2800 K and ≤4500 K CCT range were 

12.0 percent more efficacious than lamps in the >4500 K and <7000 K CCT range. Thus, the 

equations for the >2800 K and ≤4500 K equipment classes were multiplied by a scaling factor of 

0.880 to obtain the equations for the >4500 K and <7000 K equipment classes. This scaling 

factor is shown in Table 5.8.1.

5.8.4 Scaling Summary 

 In analyzing commercially available lamps, DOE found each scaling factor (bulb finish, 

luminaire characteristic, and CCT range) to be independent. Therefore, to scale from a 

representative equipment class to a scaled equipment class, DOE applied each scaling factor that 

corresponded to the differences between the two classes. Table 5.8.1 summarizes all the scaling 

factors calculated. 

Table 5.8.1 Scaling Factors

Representative Equipment Class

Scaling Factor*

Bulb Finish Luminaire 

Characteristic

CCT 

Range

≥1900 K and ≤2800 K, ≥50 W and ≤1000 W, Clear, Enclosed 0.921 N/A N/A

>2800 K and ≤4500 K, ≥50 W and ≤400 W, Clear, Enclosed 0.946 0.955 0.880

>2800 K and ≤4500 K, >400 W and ≤1000 W, Clear, Enclosed 0.946 0.955 0.880

>2800 K and ≤4500 K, >1000 W and ≤2000 W, Clear, Enclosed 0.946 0.955 0.880

**In order to calculate the efficacy requirement for a scaled equipment class, the representative equipment class 

 

p

 DOE found less than 10 CMH lamps at 2800 K and thus in the lowest CCT range, however these lamps only make 

up less than one percent of all MH lamps. 
5-63

equation is multiplied by each scaling factor of the characteristics of the equipment class that differ from the 

representative class.

5.9 SUMMARY OF ALL CANDIDATE STANDARD LEVEL EQUATIONS 

Table 5.9.1 shows the equations for all equipment classes, both representative and scaled, 

after using the scaling factors discussed in the previous section. 
5-64

Table 5.9.1 Equations for All CSLs 

CCT Range Wattage Bulb Finish*

Luminaire 

Characteristic** CSL 1 Equation CSL 2 Equation CSL 3 Equation

 and

≤ 

 W and 

≤W

Clear Enclosed lm/W = 54.0 * W0.13 N/A N/A

Open lm/W = 51.6 * W0.13 N/A N/A

Coated Enclosed lm/W = 49.7 * W0.13 N/A N/A

Open lm/W = 48.8 * W0.13 N/A N/A

 and

≤ 

 W

and ≤

W

Clear Enclosed lm/W = 45.5 * W0.10 lm/W = 50.7 * W0.10 lm/W = 48.7 * W0.13

Open lm/W = 43.5 * W0.10 lm/W = 48.4 * W0.10 lm/W = 46.5 * W0.13

Coated Enclosed lm/W = 43.0 * W0.10 lm/W = 48.0 * W0.10 lm/W = 46.1 * W0.13

Open lm/W = 41.1 * W0.10 lm/W = 45.8 * W0.10 lm/W = 44.0 * W0.13

 W 

and ≤

W

Clear Enclosed lm/W = 0.021 * W + 74.3 lm/W = 0.021 * W + 83.8 N/A

Open lm/W = 0.020 * W + 71.0 lm/W = 0.020 * W + 80.0 N/A

Coated Enclosed lm/W = 0.020 * W + 70.3 lm/W = 0.020 * W + 79.3 N/A

Open lm/W = 0.019 * W + 67.1 lm/W = 0.019 * W + 75.7 N/A

 W 

and ≤

W

Clear Enclosed lm/W = 95.3 N/A N/A

Open lm/W = 91.0 N/A N/A

Coated Enclosed lm/W = 90.2 N/A N/A

Open lm/W = 86.1 N/A N/A

  and 

 

 W and 

≤ W

Clear Enclosed lm/W = 40.0 * W0.10 lm/W = 44.6 * W0.10 lm/W = 42.9 * W0.13

Open lm/W = 38.2 * W0.10 lm/W = 42.6 * W0.10 lm/W = 40.9 * W0.13

Coated Enclosed lm/W = 37.9 * W0.10 lm/W = 42.2 * W0.10 lm/W = 40.5 * W0.13

Open lm/W = 36.2 * W0.10 lm/W = 40.3 * W0.10 lm/W = 38.7 * W0.13

 W

and ≤

W

Clear Enclosed lm/W = 0.018 * W + 65.4 lm/W = 0.018 * W + 73.7 N/A

Open lm/W = 0.018 * W + 62.4 lm/W = 0.018 * W + 70.4 N/A

Coated Enclosed lm/W = 0.017 * W + 61.9 lm/W = 0.017 * W + 69.8 N/A

Open lm/W = 0.017 * W + 59.1 lm/W = 0.017 * W + 66.6 N/A

 W 

and ≤

W

Clear Enclosed lm/W = 83.9 N/A N/A

Open lm/W = 80.1 N/A N/A

Coated Enclosed lm/W = 79.3 N/A N/A

Open lm/W = 75.8 N/A N/A

* MV lamps regardless of bulb finish are placed in the clear equipment classes for their respective CCT and wattage.

** MV and HPS lamps are placed in the enclosed equipment classes for their respective wattage and CCT.
5-65

REFERENCES 

1

 U.S. Census Bureau. Manufacturing, Mining, and Construction Statistics. Current Industrial 

Reports, Electric Lighting Fixtures, MA335L. 2001. (Last accessed February 15, 2013). 

<www.census.gov/mcd/> 

2

 Zollweg, R.J. Metal Bonding and Interactions in High Temperature Systems: with emphasis on 

alkali metals. 1982. American Chemical Society