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CHAPTER 4. SCREENING ANALYSIS

TABLE OF CONTENTS

4.1 INTRODUCTION ............................................................................................... 4-1

4.2 TECHNOLOGIES THAT DO NOT AFFECT DAILY ENERGY 

CONSUMPTION................................................................................................. 4-2

4.2.1 Higher Efficiency Expansion Valves....................................................... 4-2

4.2.2 Liquid-Suction Heat Exchangers............................................................. 4-2

4.3 SCREENED-OUT TECHNOLOGIES................................................................ 4-3

4.4 REMAINING TECHNOLOGIES ....................................................................... 4-3
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CHAPTER 4. SCREENING ANALYSIS

4.1 INTRODUCTION

This chapter addresses the screening analysis that the U.S. Department of Energy 

(DOE) conducted in support of the ongoing energy conservation standards rulemakings 

for refrigerated beverage vending machines. 

In the market and technology assessment, chapter 3 of the preliminary technical 

support document (preliminary TSD), DOE presents an initial list of technologies that 

could potentially reduce the energy consumption of refrigerated beverage vending

machines. The goal of the screening analysis is to identify any technologies that will be 

eliminated from further consideration in the rulemaking analyses. Some of the 

technologies considered in chapter 3 could potentially reduce annual energy consumption 

under certain field conditions, but may not reduce daily energy consumption (DEC), as 

measured by the DOE test procedure for refrigerated beverage vending machines. (10 

CFR 431.294) Therefore, DOE removed from consideration those technologies that do 

not reduce DEC as measured using the DOE test procedure. DOE evaluated the 

remaining technologies using the screening criteria set forth in the Energy Policy and 

Conservation Act (EPCA), as amended. (42 U.S.C. 6311–6317)

EPCA establishes criteria for prescribing new or amended standards designed to 

achieve the maximum improvement in energy efficiency. Further, EPCA directs the 

Secretary of Energy to determine whether a standard is technologically feasible and 

economically justified. (42 U.S.C. 6295(o)(2)(A)–(B) and 6313(d)(4))

Appendix A to subpart C of 10 CFR part 430, “Procedures, Interpretations and 

Policies for Consideration of New or Revised Energy Conservation Standards for 

Consumer Products” (the Process Rule), sets forth procedures to guide DOE in its 

consideration and promulgation of new or revised equipment energy conservation 

standards. These procedures elaborate on the statutory criteria provided in 42 U.S.C. 

6295(o) and, in part, eliminate problematic technologies early in the process of 

prescribing or amending an energy conservation standard. In particular, sections 4(b)(4) 

and 5(b) of the Process Rule guide DOE in determining whether to eliminate from 

consideration any technology that presents unacceptable problems with respect to the 

following criteria. To fulfill statutory criteria for amending or prescribing energy 

standards for refrigerated beverage vending machines, as established in 42 U.S.C. 

6295(o), DOE applied the provisions in the Process Rule in its screening analysis for this 

rulemaking.

Technological feasibility. Technologies incorporated in commercial equipment 

or in working prototypes will be considered technologically feasible.

Practicability to manufacture, install, and service. If mass production of a 

technology in commercial equipment and reliable installation and servicing of the 
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technology could be achieved on the scale necessary to serve the relevant market at the 

time of the effective date of the standard, then that technology will be considered 

practicable to manufacture, install, and service.

Adverse impacts on equipment utility or equipment availability. If a 

technology is determined to have a significant adverse impact on the utility of the 

equipment to significant subgroups of consumers, or result in the unavailability of any 

covered equipment type with performance characteristics (including reliability), features, 

sizes, capacities, and volumes that are substantially the same as equipment generally 

available in the United States at the time, it will not be considered further.

Adverse impacts on health or safety. If it is determined that a technology will 

have significant adverse impacts on health or safety, it will not be considered further.

In sum, if DOE determines that a technology or combination of technologies has 

unacceptable effects on the policies stated in section 5(b) of the Process Rule, those 

technologies will be eliminated from consideration. If a particular technology fails to 

meet one or more of the four criteria, it will be screened out. 

4.2 TECHNOLOGIES THAT DO NOT AFFECT DAILY ENERGY 

CONSUMPTION

DOE eliminated two technologies that were identified in the technology 

assessment because they have no significant effect on or do not significantly decrease 

DEC as measured by the DOE test procedure at 10 CFR 431.294. However, these 

features (i.e., higher efficiency expansion valves and suction line heat exchangers) could 

potentially reduce the energy consumption of the refrigerated beverage vending machine 

in field applications. Although these technologies were not considered in the analyses, 

DOE does not discourage their use by manufacturers. For each technology removed for 

this reason, DOE provided an explanation of why the technology does not affect DEC. 

4.2.1 Higher Efficiency Expansion Valves

Higher efficiency expansion valves could potentially reduce the annual energy 

consumption of refrigerated beverage vending machines by adapting to significant 

variations in loads and ambient conditions. Because the DOE test procedure does not 

include any prescribed changes in refrigerated-product loading or ambient conditions, 

there is no significant opportunity for higher efficiency expansion valves to reduce DEC

as measured under the DOE test procedure. 

4.2.2 Liquid-Suction Heat Exchangers

A liquid-suction heat exchanger (LSHX) is an indirect liquid-to-vapor heat 

transfer device that evaporates any residual liquid refrigerant that remains in the 

evaporator discharge line and thereby minimizes the risk of liquid refrigerant carrying 

over to the compressor suction. Generally, LSHXs are installed in refrigeration systems 

to ensure proper system operation and increase system performance. However, the 
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performance of an LSHX is dependent on the specific design used in a given piece of 

equipment, as well as other properties of the system and the operating conditions. A 

combination of refrigerant type, operating temperature, ambient conditions, and other 

factors determines whether an LSHX will increase or decrease the DEC as measured by 

the DOE test procedure. In some cases, an LSHX can produce enough of a pressure 

differential across the device, which requires additional compressor energy to overcome, 

that the result is a net increase in energy consumption. Because an LSHX does not 

consistently reduce DEC, DOE did not consider this technology in the engineering 

analysis.

4.3 SCREENED-OUT TECHNOLOGIES

This section typically addresses the technologies that DOE screened out because 

they did not meet the requirements of sections 4(a) and 5(b) of the Process Rule. DOE 

considers the following four factors: (1) technological feasibility; (2) practicability to 

manufacture, install, and service; (3) adverse impacts on equipment utility to consumers; 

and (4) adverse impacts on health or safety. However, in this preliminary analysis no 

technologies were screened out upon application of these four factors. 

4.4 REMAINING TECHNOLOGIES

After eliminating those technologies that do not reduce DEC, DOE is considering 

the technologies listed below in the preliminary analysis.

• higher efficiency lighting

• higher efficiency evaporator fan motors

• higher efficiency evaporator fan blades

• improved evaporator design

• low-pressure differential evaporators

• improvements to anti-sweat heaters

• improved or thicker insulation

• defrost mechanism

• higher efficiency compressors 

• variable-speed compressors

• microchannel heat exchangers

• improved condenser design

• higher efficiency condenser fan motors

• higher efficiency condenser fan blades

• improved glass pack design (for Class A machines)

• lighting controls

• refrigeration low-power modes