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CHAPTER 6.NATIONAL ENERGY SAVINGS AND CONSUMER IMPACTS

TABLE OF CONTENTS

6.1 METHODOLOGY ....................................................................................................... 6-1

6.1.1 Shipment Forecasts ........................................................................................ 6-1

6.1.2 National Energy Savings Analysis................................................................. 6-2

6.1.3 Net Present Value Analysis ........................................................................... 6-2

6.2 ESTIMATES OF POTENTIAL ENERGY AND CONSUMER IMPACTS ............... 6-3

6.2.1 National Energy Savings................................................................................ 6-3

6.2.2 Net Present Value .......................................................................................... 6-3

LIST OF TABLES

Table 6.2.1. Cumulative National Energy Savings for HID Lamps (2017–2046) ...................... 6-3

Table 6.2.2. Cumulative NPV Results for HID Lamps (2017–2046) .......................................... 6-4
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CHAPTER 6. NATIONAL ENERGY SAVINGS AND CONSUMER IMPACTS

For this determination analysis, the U.S. Department of Energy (DOE) estimated the 

following national impacts from representative energy-efficient substitutes for baseline highintensity discharge (HID) lamps: (1) national energy savings (NES), (2) monetary value of the 

energy savings due to standards, (3) increased total installed costs of the considered products due 

to standards, and (4) the net present value (NPV) of energy savings (difference between value of 

energy savings and increased total installed costs). 

DOE prepared a spreadsheet model to forecast energy savings and national consumer 

economic costs and savings resulting from new standards. The next two sections present details 

of the methodology and results of the national impact estimates.

6.1 METHODOLOGY

6.1.1 Shipment Forecasts

Shipment forecasts for HID lamps are key inputs to the NES and NPV calculations, and 

were developed by DOE using a three-step process. First, DOE used historical shipment data 

from NEMA to estimate the total historical shipments of each lamp type analyzed. Second, DOE

calculated an installed stock for each lamp type based on the average service lifetime of each 

lamp type. Third, by applying estimated market growth rates and HID lamp shipment trends, 

DOE developed annual shipment projections. 

As discussed in chapter 2, NEMA provided two sets of HID lamp shipment data for the 

periods 1990 to 2002 and 2003 to 2008. Based on the NEMA shipments data, DOE estimated the 

average annual growth rate to be 1.5 percent until 2016. DOE assumed that mercury vapor (MV) 

lamps would decline to extinction and not exist for lighting applications by 2016. DOE also 

assumed that high-pressure sodium (HPS) lamps would represent one-third of all HID lamps, and 

that metal halide lamps (both probe and pulse-start) would constitute the remaining shipments. 

Historically, probe-start metal halide (MH) has dominated total metal halide lamp shipments, but 

DOE assumed that MH shipments will gradually decrease as luminaire requirements and other 

incentives promote the use of pulse-start MH (PMH) or non-HID technologies. 

DOE assumed that the overall number of HID lamps shipped would peak near 2020. The 

following are the factors in DOE’s assumptions: 

• DOE’s metal halide lamp fixture (MHLF) rule could affect the price of fixtures. More 

efficient ballasts could require redesign of the fixtures as noted during the MHLF public 

meeting1

. The effective dates of future MHLF rules are 2015 and 2022. 

• Many non-HID technologies are competing in the traditional HID market. For instance, 

the high-bay and low-bay market, traditionally dominated by HID technology, has lost 

significant ground to the fluorescent versions of these fixtures known as high-intensity 

fluorescent (HIF). During the MHLF public meeting, DOE heard that since 2002 there 
6-2 

has been a major shift away from metal halide high-bay fixtures to fluorescent high-bay 

fixtures2

. DOE believes that this trend will continue.

• Many energy codes (both state and the Federal ANSI/ASHRAE/IESNA Standard 90.1) 

have requirements in either parking lot or structures for increased use of controls. The 

controls turn off or reduce the lighting power in response to either daylight or low 

frequency of occupants. HID technology has dominated parking lot and structure 

applications, but the control requirements will require other technologies to be 

considered. DOE believes that induction, fluorescent, and solid-state lighting will fill the 

void left by HID from the increased lighting control requirements. 

In summary, DOE assumes a growth of 1.5 percent from 2008 to 2016 in overall HID 

lamp shipments with MV trending to 0 percent by 2016, HPS consistently representing 33 

percent of the total HID shipments, and metal halide (MH and PMH) constituting the remaining 

shipments. DOE assumes that overall HID lamps will peak and chose 2016 as the year of 

maximum shipments. After 2016, DOE assumed the HID lamp shipments would decline at a rate 

of 1.5 percent per year. Under these assumptions, the total HID shipments in 2024 will be 

roughly the same number of HID lamps shipped in 2008. 

6.1.2 National Energy Savings Analysis 

The inputs for determining NES are (1) annual energy consumption per unit; (2) 

shipments; (3) equipment stock; (4) national energy consumption (calculated from consumption 

per unit and equipment stock); and (5) site-to-source conversion factors. 

DOE calculated the national energy consumption by multiplying the number of units, or 

stock, of lamp-and-ballast systems (by vintage, which represents the age of the ballasts) by the 

unit energy consumption (also by vintage). Then, DOE calculated national annual energy savings 

from the difference between national energy consumption in the base case (without efficiency 

standards) and a higher-efficiency standards case. DOE estimated energy consumption and 

savings based on site energy, and converted the electricity consumption and savings to source 

energy. Cumulative energy savings are the sum of the annual NES, which DOE determined over 

the analysis period (2017 – 2046). Cumulative NES results are presented as undiscounted and 

based on a 3- and 7-percent real discount rate.

6.1.3 Net Present Value Analysis

The inputs for determining NPV are (1) total annual installed cost, (2) total annual 

operating cost savings, (3) discount factor, (4) present value of costs, and (5) present value of 

savings. DOE calculated net savings each year as the difference between total operating cost 

savings and increases in total installed costs (including equipment price and installation cost). 

DOE calculated savings over the life of the equipment, accounting for differences in yearly 

energy rates. DOE calculated undiscounted NPV as the difference between the present value of 

operating cost savings and the present value of increased total installed costs, and used discount 

rates of 3 and 7 percent to discount future costs and savings to the present. 
6-3 

DOE calculated increases in total installed costs as the product of the difference in the 

total installed cost between the base case and standards case, with total annual shipments 

assumed as equal in both cases. Because purchase costs of the higher-efficiency equipment in the 

standards case are generally greater than the purchase costs of equipment in the base case, price 

increases appear as negative values in the NPV. DOE expressed operating cost savings as 

decreases in operating costs associated with the lower energy consumption of equipment in the 

standards case compared to the base efficiency case. Total operating cost savings are the product 

of savings per unit and the number of units of each vintage surviving in a particular year. 

6.2 ESTIMATES OF POTENTIAL ENERGY AND CONSUMER IMPACTS

DOE estimated national energy savings and consumer effects of energy conservation 

standards for the considered HID lamps using its own engineering analysis data. Cumulative 

NES values are presented in quadrillion British thermal units (quads), and NPV values are 

presented in billion 2010$. 

6.2.1 National Energy Savings 

The results using DOE’s analysis of design options indicate potential cumulative energy 

savings for medium-wattage HID lamps of 11.4 quads (undiscounted value) over a 30-year 

analysis period (2017–2046). Table 6.2.1 presents the cumulative NES values for each pairing of 

baseline and substitute lamps, as well as the total cumulative NES.

Table 6.2.1. Cumulative National Energy Savings for HID Lamps (2017–2046) 

NES Discount

quads

Baseline Lamp Substitute Lamp Undiscounted 3% 7%

175 W MV 150 W PMH -1.5 -0.9 -0.5

175 W MV 100 W HPS 0.0 0.0 0.0

250 W MV 150 W PMH -1.4 -0.9 -0.5

250 W MV 150 W HPS 0.0 0.0 0.0

400 W MV 250 W PMH -6.6 -4.1 -2.4

400 W MV 150 W HPS 0.0 0.0 0.0

175 W MH 150 W PMH 1.3 0.8 0.5

175 W MH 100 W HPS 2.8 1.8 1.0

250 W MH 175 W PMH -1.0 -0.6 -0.4

250 W MH 150 W HPS 3.9 2.4 1.4

360 W MH 320 W PMH 0.7 0.5 0.3

360 W MH 250 W HPS 5.3 3.3 2.0

400 W MH 320 W PMH 1.8 1.1 0.7

400 W MH 250 W HPS 6.1 3.8 2.3

TOTAL 11.4 7.2 4.4

6.2.2 Net Present Value

DOE estimated the national economic effect on end users in terms of the NPV of 

cumulative benefits from 2017 to 2046. The results indicate a potential NPV of $30.0 billion 

(2010$) at a 3-percent discount rate and $13.7 billion at a 7-percent discount rate. Table 6.2.2 

presents the cumulative NPV results for each pairing of baseline and substitute lamps, as well as 

the total cumulative NPV. 
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Table 6.2.2. Cumulative NPV Results for HID Lamps (2017–2046) 

NES Discount

billion 2010$ 

Baseline Lamp Substitute Lamp Undiscounted 3% 7%

175 W MV 150 W PMH -21.4 -13.4 -8.0

175 W MV 100 W HPS -0.4 -0.3 -0.3

250 W MV 150 W PMH -20.4 -12.8 -7.6

250 W MV 150 W HPS -0.4 -0.3 -0.3

400 W MV 250 W PMH -79.4 -49.8 -29.5

400 W MV 150 W HPS -0.3 -0.3 -0.2

175 W MH 150 W PMH 8.6 5.1 2.7

175 W MH 100 W HPS 30.9 19.0 10.8

250 W MH 175 W PMH -15.0 -9.9 -6.3

250 W MH 150 W HPS 40.1 24.7 14.1

360 W MH 320 W PMH -0.7 -0.8 -0.9

360 W MH 250 W HPS 49.0 30.2 17.4

400 W MH 320 W PMH 6.6 3.8 1.9

400 W MH 250 W HPS 56.1 34.7 20.0

TOTAL 53.4 29.9 13.7
6-5 

REFERENCES

1

U.S. Department of Energy–Office of Energy Efficiency and Renewable Energy. Comments 

from the Public Meeting for Framework Analysis: Energy Efficiency Program for 

Commercial and Industrial Equipment: Metal Halide Lamp Fixture. January 2010. Transcript 

for Docket DOE EERE-2009-BT-STD-0018/RIN 1904-AC00 – Comment 1.2.005 

2

 Ibid 1