A

- i APPENDIX A. IMPROVED R20 SHORT L AMP

TABLE OF CONTENTS

A.1 INTRODUCTION

.................................................................................................... A-1
A.2 INTERNAL DIMENSIONAL COMPATIBILITY OF HALOGEN BURNER
CAPSULES

................................................................................................ ................................. A-2
A.3 EFFICACY OF IMPROVED DESIGN OPTIONS

.................................................. A-3
A.4 MODELED R20 SHORT LAMPS AS SUBSTITUTES

.......................................... A-6A

- 1 APPENDIX A. IMPROVED R20 SHORT L AMP

A.1 INTRODUCTION

This appendix provides detailed information on the analysis conducted for the final rule to determine if the efficacy of 100- watt (W) R20 a short (having a maximum overall length [ MOL ] of 3 and 5/8 [or 3.625] inches) lamps (hereafter “ R20 short lamps”) could be improved to meet energy conservation standards. The existing R20 short lamps use incandescent technology and do not meet previous energy conservation standards or the existing standards that began requiring compliance in July 2012 b (hereafter “July 2012 standards”). Specifically, the U.S. Department of Energy (DOE) examined the addition of halogen capsules to existing R20 short lamps. Tungsten- halogen lamps are a specific type of incandescent reflector lamp (IRL) that contain a small diameter fused quartz envelope filled with a halogen molecule, referred to as a capsule, that surrounds the filament. The use of halogen capsules is known to improve efficacy
of IRLs. H alogen infrared ( HIR ) technology, in addition to the halogen capsules, uses coatin gs on the inside outside of the capsule that reflect infrare d light back onto the filament, while letting the visible energy pass through the coating. These infrared coatings increase the filament operating temperature, further improving lamp efficacy. In this final rule analysis, DOE modeled R20 short lamps utiliz ing HIR technology.

The halogen capsules in tungsten- halogen lamps are available in two designs: (1) a single -ended burner that contains a lead wire inside the capsule and (2) a double-ended burner that features a lead wire outside the capsule. Single

- ended burners are less efficacious than double-ended due to the presence of the lead wire inside the capsule, which prevents a certain amount of energy from reaching the capsule wall and being reflected back to the capsule
filament. Single -ended burners are a lso typically smaller in size. Hence in modeling R20 short lamps using HIR technology, DOE examined two specific scenarios, one using a single-ended
burner and the other using a double- ended burner.

DOE was unable to identify any commercially available R20 short lamps using HIR technology with single -ended or double-ended halogen burners

. Therefore, DOE used commercially available lamps from which to scale more efficacious R20 short lamps. Before doing so, DOE first confirmed through teardowns that the halogen capsules of the commercial lamp s could fit in an R20 short lamp. Section A.2 of this appendix describes the teardown tes ting conducted by DOE for th is final rule to determine if halogen capsules are dimensionally compatible with R20 short lamps. Section A.3 presents results of DOE’s modeling analysis to determine whether HIR R20 short lamps could meet energy conservation standards. Section A.4
discusses whether HIR R20 short lamps would meet the special characteristic requirements of the R20 short lamp and if an improved R20 short lamp is a potential substitute.

a “R” denotes a reflecto r lamp type and “20” denotes diameter in 1/8 inch increments, which translates to 2.5 inches.

b Existing standards were established as amendments to previous standards in a final rule published July 2009, requiring compliance in July 2012. 74 FR 34080 (July 14, 2009). Information regarding the 2009 Lamps Rule can be found at on regulations.gov, docket number EERE

- 2006

- STD

- 0131 at www.regulations.gov/#!docketDetail;D=EERE

- 2006

- STD

- 0131 and on DOE’s Building and Technologies webpage for Incandescent Reflector Lamps : http://www1.eere.energy.gov/buildings/appliance_standards/product.aspx/productid/58A

- 2 A.2 INTERNAL DIMENSIONAL COMPATIBILITY OF HALOGEN BURNER
CAPSULES

In response to a request for information c (RFI) for this rulemaking, DOE received conflicting comments regarding the feasibility of incorporating halogen capsules in R20 short lamps. Therefore, DOE performed teardowns to determine the dimensional compatibility of both single -ended and double-ended halogen capsules with R20 short lamps.

For the notice of proposed rulemaking (NOPR) analysis, d DOE had torn down two 100 W R20 short lamp models, one from each of the two known manufacturers of R20 short lamps.
DOE had also torn down one 60 W HIR PAR e 30 short lamp containing a double-ended halogen
burner. For the final rule, DOE tore down additional commercially available lamps for use in the modeling analysis of an HIR R20 short lamp. Specifically, DOE tore down one 40 W HIR R20 model containing a single-ended burner, one 45 W HIR R20 model containing a double-ended burner, and two 40 W HIR R20 models containing double-ended burners. DOE gathered internal and external dimensions of the lamp components, as well as general design information from
these teardowns.

DOE first compared the dimensions of the 100 W R20 short lamps to that of the 40 W

HIR R20 model with single -ended burner to determine if the burner could be utilized in an R20 short lamp. DOE measured the length of the reflector f of the R20 short lamp to be 67.0 mm for
the first model and 67.3 mm for the second model. DOE determined that the 40 W HIR R20 reflector length was 75.7 mm and the distance from the end of the halogen capsule to the reflector wall was 16.0 mm. Thus, the length required to fit the halogen capsule was 59.7 mm. Therefore, DOE expects that if th is halogen capsule was mounted in an R20 short lamp, there would be an additional 7.3 to 7.6 mm of vertical space between the halogen capsule and reflector
wall.

Based on the se teardown results , DOE concluded that the single -ended burner found in
the 40 W HIR R20 lamp is dimensionally compatible with an R20 short lamp.

DOE also compared the dimensions of the 100 W R20 short lamps to that of the HIR R20 lamps with double-ended burners to determine dimensional compatibility. As stated previously, DOE measured the length of the reflector of the R20 short lamp to be 67.0 mm for the first
model and 67.3 mm for the second model. For the 45 W HIR R20 model with a double-ended burner, DOE determined that the reflector length was 72.3 mm and the distance from the end of the halogen capsule to the reflector wall was 4.9 mm. Thus, the length required to fit the halogen capsule of the 45 W HIR R20 was 67.4 mm, which was greater than the reflector length of both R20 short lamp model s.

c The RFI and associated comments can also be found at regulations.gov under Docket No. EERE

– 2010

– BT

– PET

– 0047

. d Appendix A from the NOPR can be found on regulations.gov, under docket number EERE

– 2010

– BT

– PET

– 0047

, at www.regulations.gov/#!docketDetail;D=EERE

- 2010

- BT

- PET

- 0047

.
e “PAR” denotes a parabolic aluminum reflector lamp type

. f The length of the reflector is the distance from the top of the lamp base to the end of the reflector.A

- 3 DOE also examined two 40 W HIR R20 models containing double-ended burners. F or the first 40 W HIR R20 model, DOE measured the reflector length to be 74.4 mm and the distance from the end of the halogen capsule to the reflector wall was 6.2 mm. The length required to fit the halogen capsule of this lamp was therefore 68.2 mm, which was greater tha n the reflector length of both R20 short lamp models. For the second 40 W HIR R20 model, DOE determined that the reflector length was 74.1 mm and the distance from the end of the halogen capsule to the reflector wall was 7.7 mm. Therefore, the length required for the halogen capsule was 66.4 mm, which was 0.6 mm less than the reflector length of the first R20 short lamp model and 0.9 mm less than the reflector length of the second.

Based on the se teardown results, DOE found that the required length of the 45 W HIR
R20 double-ended burner and one model of 40 W HIR R20 double-ended burner w ere greater than the measured length of the R20 short lamp reflector. For the second 40 W HIR R20 model,
b ecause there would be less than 1 mm of space between the halogen capsule and reflector wall when mounted in the R20 short lamp, DOE determined it would be extremely difficult to reliablyfit the double-ended burner in an R20 short lamp. Therefore, DOE concluded that the doubleended burners found in the commercially available HIR R20 lamps were not dimensionally compatible with the R20 short lamps.

However, as stated previously, DOE conducted a teardown of a 60 W HIR PAR30 short lamp with a double-ended burner i n the NOPR analysis . DOE determined based on a similar teardown analysis that the halogen capsule found in the 60 W HIR PAR30 short lamp could fit in an R20 short lamp. Thus, DOE maintains that double-ended burners exist that are dimensionally compatible w ith R20 short lamps.

Therefore, t hrough the results of the independent teardown testing discussed in this
section , DOE was able to confirm that a single

- ended burner from a 40 W HIR R20 lamp and a
double-ended burner from a 60 W HIR PAR30 short lamp would fit in an R20 short lamp . DOE then proceeded to use these commercially available lamps to model a more efficacious R20 short lamp.

A.3 EFFICACY OF IMPROVED DESIGN OPTIONS

After establishing that single -ended and double-ended halogen burners are dimensionally compatible with R20 short lamps, DOE next performed testing to determine the potential improvement in efficacy for R20 short lamps through the use of these technologies. As mentioned previously, DOE was unable to identify any R20 short lamps using HIR technology with single -ended or double-ended burners. Therefore, to determine the improvement in efficacy of a 100 W R20 short lamp using these technology options , DOE deve loped theoretical models by scaling from commercially available product s.

A.3.1 Single

- Ended Burner Modeling Analysis

DOE tested the efficacy of the 120 V, 40 W HIR R20 lamp that contained a dimensionally compatible single -ended burner to determine the lamp’s performance. Next, DOEA

- 4 used Illuminating Engineering Society of North America ( IESNA ) equations relating lifetime, lumens, and wattage to scale the 40 W HIR R20 lamp to meet the performance specifications (i.e., lumen output and lifetime) of the R20 short lamp. DOE conducted three modeling scenarios, scaling the lumen output of the 40 W lamp to be comparable to the minimum, maximum, and average lumen output of the established performance range (637 and 1,022 lumens) of R20 short lamps. Typically R20 short lamps have a lifetime of 2,000 or 2,500 hours. For this analysis, DOE assumed the maximum rated lifetime of 2,500 hours. The results of this scaling analysis are presented in Table A.1

.

Table A.1 Results of R20 Short Lamp Single

- Ended Burner Modeling Analysis Scaling
Scenario Lifetime (hours) Lumens Watts (W) Efficacy (lm/W) Standard g

Average lumen
output 2,500 828.8 55 15.1 14.8

Maximum lumen output 2,500 1,011.1 66 15.3 15.5

Minimum lumen output 2,500 649.8 44 14.8 N/A h

Based on these results, DOE determined that the efficacy of an R20 short lamp improves with the use of a single -ended halogen burner. The efficacy of the 100 W R20 short lamp was measured to be 8.5 lumens per watt (lm/W), while the theoretical efficacy of the modeled HIR R20 short lamp with single-ended burner was calculated to be between 14.8 lm/W and 15.3
lm/W. For the average lumen output scenario, the efficacy of the modeled lamp improved to
meet the July 2012 standards. For the maximum lumen output scenario, the efficacy of the modeled lamp did not meet the July 2012 standards. In the case of the minimum lumen output scenario, the modeled lamp wattage was reduced to lower than 45 W, thereby excluding the lamp from existing standards for IRLs specified in 10 CFR 430.32(n)(5). i

A.3.2 Double

- Ended Burne r Modeling Analysis

DOE utilized a similar scaling process to determine if the incorporation of a double

ended halogen burner would successfully increase the efficacy of an R20 short lamp by a
sufficient amount to meet the July 2012 standards. As stated previously, DOE found, based on teardowns, that the double-ended burners found in commercially available HIR R20 lamps were likely not dimensionally compatible with the R20 short lamp. DOE did however identif y a commercially available 120 V, 60 W HIR PAR30 short lamp that contained a double- ended burner that was dimensionally compatible with an R20 short lamp (see section A.2 ) in the NOPR analysis

. Therefore, D OE maintained the use of the 60 W HIR PAR30 short lamp to model an R20 short lamp with double-ended burner. As noted previously, due to the lead wire being outside of the capsule, a double -ended burner is more effic acious than a single-ended burner, and
th erefore, could possibly result in an even more efficacious R20 short lamp.

g The minimum efficacy required by existing IRL standard specified in 10 CFR 430.32(n)(5)

, given the modeled lamp wattage.

h This lamp is excluded from the existing IRL standards specified in 10 CFR 430.32(n)(5). See 10 CFR 430.32(n)(6)(ii) for a list of exclusions.

i For a full list of exclusions see 10 CFR 430.32(n)(6)(ii).A

- 5 DOE acknowledges that a lamp’s reflector efficiency, which affects the overall lamp efficacy, is dependent on the envelope shape. Therefore, DOE applied the efficiency of R20

- shaped reflectors to the efficacy of the HIR PAR30 short lamp burner with PAR- shape reflector removed. For the final rule, DOE revised the analysis to examine both an average reflector efficiency

, as well as a higher reflector efficiency , as suggested in a joi nt comment by California
investor- owned utilities . (CA IOUs, No. 16 at p. 2) During p revious reflector efficiency testing, DOE determined the average reflector efficiency of R20 -shaped lamps to be 62.2 percent. Of the R20 lamp models tested, DOE identified a higher performing lamp model that had a reflector efficiency of 66.3 percent. I n order to determine the efficacy of the double-ended halogen burner
with an R- shaped reflector efficiency , DOE applied the average reflector efficiency value of 62.2 percent to the tested efficacy of the HIR PAR30 short lamp’s halogen capsule with the PARshaped r eflector removed. DOE then repeated this assessment using the higher reflector efficiency value of 66.3 percent

.

Next, DOE used IESNA equations relating lifetime, lumens, and wattage to scale the resulting theoretical 60 W HIR R20 lamps to meet the performance specifications (i.e., lumen output and lifetime) of the R20 short lamp. DOE first conducted three modeling scenarios for the HIR R20 lamp with double-ended burner and average reflector efficiency , scaling the lumen output to be comparable to the minimum , maximum, and average lumen output of the established performance range (637 and 1,022 lumens) of R20 short lamps. As stated previously, R20 short lamps typically have a lifetime of 2,000 or 2,500 hours. For this analysis, DOE again assumed the maximum rated lifetime of 2,500 hours. The results of this scaling analysis are presented in
Table A.2

.

Table A.2 Results of R20 Short Lamp Double

- Ended Burner with Average Reflector Efficiency Modeling Analysis Scaling
Scenario Lifetime (hours) Lumens Watts (W) Efficacy (lm/W) Standard j

Average lumen
output 2,500 839.9 58 14.5 15.0

Maximum lumen output 2,500 1

, 031.0 70 14.7 15.7

Minimum lumen output 2,500 652.3 46 14.2 14.1

Based on the results of these scaling calculations, DOE determined that the efficacy of an R20 short lamp improves using a double-ended halogen burner with average reflector efficiency applied . The efficacy of the 100 W R20 was measured to be 8.5 lm/W, while the ef ficacy of the
modeled HIR R20 short lamp with double- ended burner and average reflector efficiency was calculated to be between 14.2 lm/W and 14.7 lm/W. For the average lumen output and maximum lumen output scenarios, the efficacy of the modeled lamps did not meet the July 2012 standards. However, for the minimum lumen output scenario, the efficacy of the modeled lamp improved to

meet the July 2012 standards.

j The minimum efficacy required by existing IRL standard specified in 10 CFR 430.32(n)(5) given the modeled lamp wattage.A

- 6 DOE then conducted the same analysis for the HIR R20 lamp with double-ended burner and higher reflector efficiency. DOE again scaled the lumen output to be comparable to the minimum, maximum, and average lumen output of the established performance range (637 and 1,022 lumens ) of R20 short lamps. DOE assumed the maximum rated lifetime for R20 short lamps of 2,500 hours. The results of the scaling analysis are presented in Table A.3

.

Table A.3 Results of R20 Short L amp Double

- Ended Burner with Higher Reflector Efficiency Modeling Analysis Scaling
Scenario Lifetime (hours) Lumens Watts (W) Efficacy (lm/W) Standard k

Average lumen
output 2,500 828.1 54 15.3 14.7

Maximum lumen output 2,500 1

, 013.7 65 15.6 15.4

Minimum lumen output 2,500 646.0 43 15.0 N/A l

DOE determined through the scaling calculations that the efficacy of an R20 short lamp improves further with the use of a double-ended halogen burner and higher reflector efficiency applied . The efficacy of the 100 W R20 was measured to be 8.5 lm/W, while the efficacy of the modeled HIR R20 lamp with double-ended burner and higher reflector efficiency was calculated
to be between 1 5.0 lm/W and 1 5.6 lm/W. For the average lumen output and maximum lumen output scenario s, the efficacy of the modeled lamp s improved to meet the July 2012 standards. In the case of the minimum lumen output scenario, the modeled lamp wattage was reduced to lower than 45 W, thereby excluding the lamp from existing standards for IRLs specified in 10 CFR 430.32(n)(5). m

A.4 MODELED R20 SHORT LA MPS AS SUBSTITUTES

DOE believes there is uncertainty with the results of the modeling analysis presented in
section A.3 due to the difference in MOL of the commercially available R20 lamps used for scaling . Because no R20 short lamps exist with halogen technology, DOE had to scale from lamp s that have longer MOLs than the R20 short lamp’s 3.625 inches. The scaling analys is for the HIR R20 lamp with a single -ended burner was based on such a standard R20 lamp. Similarly

, when modeling the HIR R20 lamps with double-ended burners, DOE utilized the reflector efficiencies of standard R20 lamps. DOE used these efficiencies because t esting the efficiency of a reflector requires the lamp to contain a halogen capsule. The lumen output of the lamp is first measured with the reflector intact. Next, the lumen output of the halogen capsule alone is
measured. The reflector efficienc y is then calculated as the ratio of the lamp lumen output to the

k The minimum efficacy required by existing IRL standard specified in 10 CFR 430.32(n)(5)

, given the modeled lamp wattage.

l This lamp is excluded from the existing IRL standards specified in 10 CFR 430.32(n)(5). See 10 CFR 430.32(n)(6)(ii) for a list of exclusions.

m For a full list of exclusions see 10 CFR 430.32(n)(6)(ii).A

- 7 capsule lumen output. As no commercially available R20 short lamps utilize halogen technology, DOE was unable to test the reflector efficiency of R20 short lamps.

DOE attempted to determine if a relationship between efficacy and MOL exists in order to account for the difference in MOL with the modeled lamps. DOE compared the catalog efficacy of standard length and long length halogen lamps that had the same shape, diameter, lifetime, voltage , and wattage, and could not find a consistent relationship between lamp length and efficacy. DOE found that efficacy sometimes increased with increased MOL, sometimes decreased, and in other cases there was no change in efficacy when there was a change in MOL. Therefore, it is unclear if shortening the length of the reflector would impact the efficacy of the improved R20 short lamp models.

DOE evaluated whether the standards-compliant R20 short lamps based on the modeling successfully replicated the neces sary performance specifications of lumen output and beam spread using the theoretical calculations described in section A.3

. Based on its theoretical modeling, DOE determined that an HIR R20 short lamp may be able to achieve lumen output within the established range for R20 short lamp of 637 to 1,022 lumens. However, because the position of the filament affects the beam angle, DOE anticipates that the beam angle cou ld be affected by the use of a halogen capsule. Because standards -compliant R20 short lamps are not commercially available, DOE is unable to confirm the beam angle of R20 short lamps that utilize an HIR capsule.

The refore, the results of the modeling ana lysis were inconclusive. While the theoretical analysis for each of the three modeled lamps (i.e.

, HIR with single -ended burner, HIR with double-ended burner and average reflector efficiency, and HIR with double-ended burner and higher reflector efficiency ) resulted in at least one potentially compliant lamp, some of the scenarios indicated the lamp could not be improved to meet standards and remain within the required lumen range for an R20 short lamp. Additionally , it is unclear if the variation in reflector length would impact the modeled efficacy and it is unknown if the standards- compliant lamp would be able to achieve the special characteristics of the R20 short lamp.