CHAPTER 3. MARKET AND TECHNOLOGY ASSESSMENT

TABLE OF CONTENTS 3.1 INTRODUCTION ........................................................................................................... 3-1 3.1.1 Definitions............................................................................................................ 3- 1 3.1.2 Description of Refrigerated Bo ttled or Canned Beverage Vending Machines.............................................................................................................. 3-2 3.2 TEST PROCEDURES..................................................................................................... 3-4 3.2.1 Department of Energy.......................................................................................... 3-4 3.3 DOMESTIC AND INTERNATIONAL RE GULATORY AND NON-REGULATORY ACTIVITIES.................................................................................................................... 3 -5 3.3.1 ENERGY STAR .................................................................................................. 3-5 3.3.2 Canadian Standards Association.......................................................................... 3-7 3.3.3 California Energy Commission............................................................................ 3-8 3.3.4 Australia............................................................................................................... 3 -9 3.3.5 Rebate Programs .................................................................................................. 3-9 3.4 MARKET ASSESSMENT ............................................................................................ 3-10 3.4.1 Trade Associations............................................................................................. 3-10 3.4.2 Manufacturers and Market Share....................................................................... 3-11 3.4.2.1 Small Businesses.................................................................................... 3-12 3.4.3 Equipment Classes............................................................................................. 3-12 3.4.4 Typical Refrigeration System ............................................................................ 3-13 3.4.5 Energy Savings Potential ................................................................................... 3-15 3.4.6 Barriers to Efficiency Improvements................................................................. 3-16 3.4.7 Market Performance Data.................................................................................. 3-16 3.5 TECHNOLOGY ASSESSMENT.................................................................................. 3-19 3.5.1 Higher Efficiency Lighting................................................................................ 3-19 3.5.2 Higher Efficiency Lighting Ballasts .................................................................. 3-20 3.5.3 Higher Efficiency Evaporator Fan Motors ........................................................ 3-20 3.5.4 Evaporator Fan Controls.................................................................................... 3-21 3.5.5 Higher Efficiency Evaporator Fan Blades ......................................................... 3-21 3.5.6 Improved Evaporator Design............................................................................. 3-21 3.5.7 Low Pressure Differential Evaporators.............................................................. 3-22 3.5.8 Improved or Thicker Insulation ......................................................................... 3-22 3.5.9 Improved Glass Pack (for Class A machines) ................................................... 3-23 3.5.10 Defrost Mechanism............................................................................................ 3-23 3.5.11 Thermoacoustic Refrigeration ........................................................................... 3-24 3.5.12 Magnetic Refrigeration ...................................................................................... 3-24 3.5.13 Electro-hydrodynamic Enhanced Heat Transfer................................................ 3-24 3.5.14 Copper Rotor Motors ......................................................................................... 3-25 3.5.15 Higher Efficiency Compressors......................................................................... 3-25 3.5.16 Improved Condenser Design.............................................................................. 3-25 3.5.17 Higher Efficiency Condenser Fan Motors ......................................................... 3-26 3.5.18 Higher Efficiency Condenser Fan Blades.......................................................... 3-26 3.5.19 Higher Efficiency Expansion Valves................................................................. 3-26

3-i3-ii 3.5.20 Variable-Speed Compressors............................................................................. 3-27 3.5.21 Liquid Suction Heat Exchangers ....................................................................... 3-27 3.5.22 Condenser Fan Motor Controllers ..................................................................... 3-27 REFERENCES ..................................................................................................................... .....3-29

LIST OF TABLES

Table 3.2.1 American Society of Heating, Refrigerating, and Ai r-Conditioning Engineers Standard 32.1-2004 – Test Conditions.................................................................... 3-5 Table 3.3.1 ENERGY STAR Criteria for Beverage Vending Machines .................................... 3-6 Table 3.3.2 California Energy Comm ission – Performance Standards

...................................... 3-8 Table 3.3.3 Beverage Vending Machine Rebate Programs

...................................................... 3-10 Table 3.4.1 Beverage Vending Mach ine Census and Energy Use Data ................................... 3-11 Table 3.4.2 Small Business Manufacture rs of Beverage Vending Machines ........................... 3-12 Table 3.4.3 Energy Use by Componen t for Typical Vending Machines .................................. 3-14 Table 3.4.4 Potential Energy Savings Es timates for Beverage Vending Machines

................. 3-15

LIST OF FI GURES

Figure 3.1.1 A typical glass-front beverage vending machine .................................................... 3-3 Figure 3.1.2 A typical solid-door beve rage vending machine

.................................................... 3-4 Figure 3.3.1 ENERGY STAR Qualified Refr igerated Beverage Vending Machine Models ..................................................................................................................... 3-7 Figure 3.4.1 Market Performance Data fo r California Energy Co mmission Qualified Class A Equipm ent Class ...................................................................................... 3-17 Figure 3.4.2 Market Performance Data fo r California Energy Co mmission Qualified Class A Equipm ent Class ...................................................................................... 3-17 Figure 3.4.3 Market Performance Data fo r California Energy Co mmission Qualified Class B Equipm ent Class ...................................................................................... 3-18 Figure 3.4.4 Market Performance Data fo r ENERGY STAR Class A Equipment Class

......... 3-18 Figure 3.4.5 Market Performance Data fo r ENERGY STAR Class B Equipment Class

......... 3-19CHAPTER 3. MARKET AND TECHNOLOGY ASSESSMENT

3.1 INTRODUCTION

This chapter details the market and technology assessment that the U.S. Department of Energy (DOE) has carried out in support of the energy conservation standards rulemaking for beverage vending machines (BVMs). This rulemaking is mandated by the Energy Policy Act of 2005 (EPACT 2005) and is effective for equipm ent manufactured on or after August 8, 2012. The beverage vending machines have never befo re been the subject of energy conservation regulations at th e federal level.

This chapter consists of two sections: the market assessment and the technology assessment. The goal of the market assessmen t is to develop a qualitative and quantitative characterization of the BVM industry and mark et structure, based on publicly available information as well as data and information submitted by manufacturers and other stakeholders. Issues that are addressed include manufacturer characteristics and market shares, existing regulatory and non-regulatory efficiency improveme nt initiatives, equipment classes, and trends in equipment markets and characteristics. The goal of the technology assessment is to develop a preliminary list of technologies that could be us ed to improve the efficiency of beverage vending machines.

Refrigerated beverage vending machines are used to cool and di spense bottled and canned beverages upon payment. This equipment is primarily used in manufacturing facilities, office buildings, retail sites, schools, colleges and other institutional bu ildings. The current installed base of beverage vending machines oper ating in the United States consumes more than 12 billion kilowatt hours (kWh ) of electricity annually. 1

3.1.1 Definitions

Section 135(c)(4) of EPACT 2005 amended section 325 of the Energy Policy and Conservation Act (EPCA) to include new s ubsections 325(v)(2), (3 ) and (4) (42 U.S.C. 6295(v)(2)-(4)), which mandates that DOE issue by rule, no later than August 8, 2009, energy conservation standards for refrigerated bottled or canned beverage vending machines manufactured three years after the date of publi cation of the final rule establishing the energy conservation standards.

Section 135(a)(3) of EPACT 2005 amended sec tion 321 of EPCA by adding, in part, new subsection 321(40), 42 U.S.C. 6291(40), whic h establishes the following definitions:

 The term “refrigerated bottled or can ned beverage vending machine” means a commercial refrigerator (defined below) th at cools bottled or canned beverages and dispenses the bottled or ca nned beverages on payment.

In addition, section 136(a)(3) of EPAC T 2005 amended section 340 of EPCA by replacing subsection 340(9), 42 U.S.C 6311(9), with, in part, definitions for the following terms relating to commercial refrigeration equipment th at are relevant to beverage vending machines:

3-1(9) (A) The term “commercial refrigerat or, freezer, and refrigerator-freezer” means refrigeration equipment that—

(i) is not a consumer product (as defined in section 321);

(ii) is not designed and marketed ex clusively for medical, scientific, or research purposes;

(iii) operates at a chil led, frozen, combination chilled and frozen, or variable temperature;

(iv) displays or stores merchandi se and other perishable materials horizontally, semivertic ally, or vertically;

(v) has transparent or solid door s, sliding or hinged doors, a combination of hinged, sliding, tran sparent, or solid doors, or no doors;

(vi) is designed for pull-down te mperature applications or holding temperature applications; and

(vii) is connected to a self-contain ed condensing unit or to a remote condensing unit.

As presented above, section 135(a)(3) of EPACT 2005 defines a “refrigerated bottled or canned beverage vending machine, ” in part, as equipment that cools bottled or canned beverages and dispenses them on payment. In the Framework document, DOE considered the definitions for “bottle” and “can” established in American National Standards Institute (ANSI)/American Society of Heating, Refrigerating, and Air-C onditioning Engineers (ASHRAE) Standard 32.1– 2004, which are:

bottle: a glass or plastic container in which a beverage is sealed.

can: a container made of metal or paperboa rd or a combination of both in which a beverage is sealed.

A bottle or can in this context refers to “a se aled container for beverages,” so a bottled or canned beverage is “a beverage in a sealed cont ainer.” DOE expects that such broad definitions for “bottled beverage” and “canne d beverage” would allow for more comprehensive coverage of existing beverage vending machine equipment, and particularly of certain types of equipment that are currently experiencing market growth.

3.1.2 Description of Refrigerated Bottled or Canned Beverage Vending Machines

Refrigerated bottled or canned beverage vendi ng machines can be divided into categories by either machine use designation (indoor use only or indoor/outdoor use) or by door type (glass3-2front or solid-door). The classification of beverage vending machines by machine use designation of indoor use only and indoor/outdoor use is ex plained in detail below.

Figure 3.1.1 A typical glass-front beverage vending machine

The beverage vending machines intended fo r indoor use only are dominated by glassfront models (shown in Figure 3.1.1 ) that have a transparent panel which enables a purchaser to see the merc handise as it is vended. In this type of machine, the merchandise itself is illuminated and used to attract th e purchaser’s attention. 2 These machines are found primarily indoors because the glass fronts make them vulnerable to vandalism in addition to introducing the problem of solar gain and heat loss through the glass front. These machines are marked “For Indoor Use Only” in accordance with Underw riters Laboratories (UL) Standard 541– 2003. 3 The glass-front vending machines are also know n as “multi-package” vending machines. This design allows the consumer to see the merchandi se inside the machine – commonly displayed on shelves

− with some models displaying as many as 45 different varieties of drinks. Product packaging is not limited to cans and bottles, and may also include cartons, juice packs, and nonstandard bottle and can shapes. Upon dispensa tion, many machines have a mechanism to move the merchandise to the door gent ly rather than dropping the beve rage from the upper shelves. With the increasing market for non-carbonated soft dr inks, such as energy dr inks, fruit juices and water (which come in a variety of packaging types and sizes), these machines provide a much wider choice for the consumer. These glass-front machines are also referred in the industry as “shelf-style” or “fully-cooled” machines, because the entire refrigerated volume needs to be cooled, not just the next -to-be-vended product.

The most common beverage vending machine that is intended for both indoor and outdoor use is the solid-door machine (or closed-front machine) (shown in Figure 3.1.2 ) Closedfront machines house cans or bottles inside a co mpletely opaque insulated com partment. With solid-door machines, the vended pr oduct cannot be seen and the mach ine either has signage or a backlit panel on the front advertising the contents. The unlit machine (signage only) is typical of machines placed in external locations. Dependi ng on the model, these machines can contain up to 800 cans and up to 12 varieties of beverages. A small fracti on of solid-door vending machines are classified as having a “live di splay” door type, where a sample of product offerings is visible to the consumer. Some of these machines show a non-vendible version of the product in a small glass window, although the front door is predominantly solid.

3-3Figure 3.1.2 A typical solid-door beverage vending machine

These machines are typically designed so th ey can be placed outdoors and can withstand weather effects. The machines intended for both indoor and outdoor use are marked “Suitable for Outdoor Use” or “Suitable for Protected Lo cations” in accordance with UL Standard 541- 2003. 3 These solid-door machines are referred to in the industry as “s tack-style” or “zonecooled” machines, because cold air is directed onl y at the fraction (or zone) of the refrigerated volume that contains the ne xt-to-be-vended product.

3.2 TEST PROCEDURES

3.2.1 Department of Energy

Section 135(b) of EPACT 2005 amends sect ion 323 of EPCA by adding, in part, new subsection 323(b(15), 42 U.S.C. 6293(b)(15), which requires that the test procedure for refrigerated bottled or canned beverage vending machines be based on ANSI/ASHRAE) Standard 32.1–-2004, Methods of Testing for Rating Vendi ng Machines for Bottled, Canned or Other Sealed Beverages. 4 DOE therefore published a final rule on December 8, 2006, incorporating the ANSI/ASHRAE Standard 32.1-2004 with two modifications by reference into section 431.294 of subpart Q to Title 10, Code of Federal Regulations Part 431 (10 CFR Part 431) for the measurement of energy consumpti on and determination of capacity of this equipment. The first modification DOE ma de in adopting ANSI/ASHRAE Standard 32.1–2004 was to specify in the final rule that in secti on 6.2, “Voltage and Freque ncy,” equipment with dual nameplate voltages should be tested at the lower of the two voltage s only. The second modification DOE made was to specify that the measurement of “vendible capacity” of refrigerated bottled or canned beverage vending machines should be in accordance with the second paragraph of section 5, “Vending Machine Capacity,” of ANSI/ASHRAE Standard 32.1– 2004, and that the measurement of “refrigerated volume” of refrigerated bottled or canned beverage vending machines should be in accordan ce with the methodology specified in section 5.2, “Total Refrigerated Volume,” (excl uding subsections 5.2.2.2 through 5.2.2.4) of the ANSI/Association of Home Appliance Ma nufacturers (AHAM) HRF Standard 1–2004, ‘‘Energy, Performance and Capacity of Househol d Refrigerators, Refrigerator-Freezers and Freezers.” 5

The current version of ANS I/ASHRAE Standard 32.1–2004:

3-4 Defines standard bottled, canned, or ot her sealed beverage storage capacity,

 Establishes uniform methods of testing for determining laboratory performance of vending machines for bottled, canne d, or other sealed beverages

 Defines the following tests and test conditions as shown in Table 3.2.1 below:

○ Energy Consumption Test is designed to determ ine the stabilized daily and unit energy consumption of the vending machine over a 24-hour period.

○ Vend Test is designed to determine how much cold product a machine will deliver, at the required temperature, when products are vended at a rate of two per minute, three hours after a half-full machine is refilled.

○ Recovery Test is designed to determine the product temperatur e recovery time of a vending machine when loaded with pr oduct at a specified temperature.

Table 3.2.1 American Society of Heating Refr igerating and Air-Conditioning Engineers Standard 32.1-2004 – Standard Test Conditions

Test and Pretest Conditions Energy Consumption Tests Vend Test Recovery Test

Ambient Temperature Perform twice: At 90±2°F (32.2±1°C) and at 75°F±2°F (23.9±1°C) 90±2°F (32.2±1°C) 90±2°F (32.2±1°C)

Relative Humidity 65±5% for 90±2°F test and 45±5% for 75±2°F test 65±5% 65±5%

Reloaded Product Temperature

__ 90±1°F (32.2±0.5°C) 90±1°F (32.2±0.5°C) Average Beverage Temperature (for test) 36±1°F (2.2±0.5°C) Throughout Test 40°F or less (4.4°C or less) Final Temperature 33-40°F (0.6-4.4°C) Final Temperature Average Beverage Temperature (for pretest conditions) Not Applicable 36±1°F (2.2±0.6°C) Pretest Conditions 36±1°F (2.2±0.6°C) Pretest Conditions

3 .3 DOMESTIC AND INTERNATIONAL REGULATORY AND NONREGULATORY ACTIVITIES

Both Canada and the State of California have efficiency standards in place for refrigerated beverage vending machines. Australi a has several efficiency standards in place for beverage vending machines. In addition, th e voluntary ENERGY STAR labeling program has been in place since 2004.

3.3 .1 ENERGY STAR

The Environmental Protection Agency (EPA ) has developed voluntary performance standards for beverage vending machines as pa rt of the ENERGY STAR labeling program. ENERGY STAR is a two-tiered st andard with the first tier effective since April 1, 2004, for new machines and April 31, 2006, for rebuilt machines. Tier 2 went into effect on July 1, 2007, for new machines. Originally, the Tier I standard was set to qualify the top 25 percent most efficient

3-5 bvm_nopr_tsd_chapter03.docmmachines. But, with Tier 2 now implemented, some manufacturers are already producing even more efficient machines.

ENERGY STAR performance criteria for qualification are dependent on vendible capacity. a In order to qualify, mode ls must meet the requirements for energy use shown in Table 3.3.1

.
Table 3.3.1 ENERGY STAR Criteria fo r Beverage Vending Machines
Equipment Type ENERGY STAR Definiti on Energy Consumption Under Test Conditions

Tier 1 (effective April 1, 2004) Tier 2 (effective July 1, 2007) Beverage vending machines A self-contained system designed to accept consumer payments and dispense bottled, canned, and other sealed beverages at appropriate temperatures without on-site labor intervention. Y = 0.55 x [8.66 + (0.009 x C)] Y = 0.45 x [8.66 + (0.009 x C)]

Where Y = 24-hour consumption (kWh/day) after the machine has stabilized, and C = vendible capacity (number of cans).

a Vendible capacity is defined in ASHRAE Standard 32.1-2004 as “the maximum quantity of standard product that can be dispensed from one full loading of the vending machine without further reload operations when used as recommended by the manufacturer. The standard product shall be 12-oz. (355 ml) cans for machines that are capable of dispensing 12-oz. (355 ml) cans. For all other machines, the standard product shall be the product specified by the manufacturer as the standard product.”

3-6 bvm_nopr_tsd_chapter03.docmFigure 3.3.1 shows the energy consumption of manufactured units that qualify for ENERGY STAR Tier II, as of May 1, 2009. 6

Figur e 3.3.1 ENERGY STAR Qualified Refrig erated Beverage Vending Machine Models

3 .3.2 Canadian Standards Association

The Canadian Standards Association (CSA) te st standard for beverage vending machines is CAN/CSA Standard C804–96, Energy Performance of Vending Machines . The CSA standard sets out minimum performance criteria for a nnual energy consumption that vary with the category of vending machine. The standard also contains the test procedure. The standard is voluntary in all jurisdicti ons in Canada, except in:

 Ontario, where these criteria are regulated by the Province of Ontario's Energy Efficiency Act (Ontario Regulation 82/95, amended to O. Reg 18/02) and apply to products manufactured, sold or leased after April 1, 2003, and

 New Brunswick, where these criteria are regulated in Regulation 95-70 of the New Brunswick Energy Efficiency Act (O.C. 95- 555), and apply to pr oducts manufactured, sold, or leased after August 31, 2004.

In Canada, beverage vending machines ar e regulated to the CSA standard and not covered under a voluntary labeling program. The maximum daily energy consumption allowed under the CSA standard is described by the following:

3-7 bvm_nopr_tsd_chapter03.docmY = 8.66 + (0.009 x C) Eq. 3.1

where Y = 24-hour consumption (kWh/day) after th e machine has reached a stable operating condition, and C = vendible capacity.

The ENERGY STAR performance levels are 45 to 55 percent more efficient than those specified in the CSA standard. In 2004, CSA proposed to regulate the energy efficiency levels of bottled and canned beverage vend ing machines to the ENERGY ST AR Tier 1 levels – thereby harmonizing with the California Energy Commission (CEC). The California levels were chosen rather than those of CSA Standard C804–96 beca use the market data available to the CSA indicate that regulating to the CSA standard would have litt le effect on the market, since the major manufacturers are already working toward the more stringent California standard. The only major difference is that the CSA proposes to move to the ENERGY STAR Tier 2 levels effective January 1, 2008.

3.3.3 California Energy Commission

CEC’s tiered specification regulates the mini mum energy performance of equipment sold in California. The Amendments to Appliance Efficiency Regulations, California Code of Regulations 7 propose both an energy efficiency standa rd and a design standard for beverage vending machines, as of January 1, 2006. (See Table 3.3.2 .)

Table 3.3.2 California Energy Commi ssion – Performance Standards Maximum Daily Energy

Consumption (kWh) Product CEC Definition January 1, 2006 January 1, 2007 Design Standard

Refrigerated canned and bottled beverage vending machines when tested at 90°F ambient temperatureexcept multipackage units. 0.55 x (8.66 + (0.009 x C) 0.55 x (8.66 + (0.009 x C) Beverage Vending Machine Refrigerated canned and bottled beverage vending machines shall be equipped with hard wired controls and/or software capable of automatically placing th e machine into a lowpower mode during periods of extended inactivity while still connected to its power source. The machine sh all be capable of operating in each of the low power mode states described below: (A) Lighting low power state – lights off for an extended period. Refrigerated multi-package canned and bottled beverage vending machines when tested at 75°F ambient temperature. 0.55 x (8.66 + (0.009 x C) 0.55 x (8.66 + (0.009 x C) (B) Refrigeration low power state – the average beverage temperature is allowed to rise above 40 degrees Fahrenheit (°F) for an extended period of time. (C) Whole machine low power state – the lights are off and the refrigerat ion operates in its low power state. (D) The machine shall be capable of

3-8 bvm_nopr_tsd_chapter03.docmau to matically returning itself back to its normal operating conditions at the conclusion of the inactivity period. The low power mode related controls/software shall be capable of on-site adjustments by the vending operator or machine owner.

3.3.4 Australia

T he National Appliance and Equipment En ergy Efficiency Committee (NAEEEC) has 15 minimum energy performance standards (MEPS) for a variety of technologies. Report No: 2008/10, Refrigerated Beverage Vending Machines , released in September 2008. 8 Its standards are based on the North American work of the Canadian Standards Association, the California Energy Commission, and the U.S. ENERGY STAR program.

N AEEEC has introduced effi ciency regulations by:

 MEPS should be implemented based on daily energy consumption. Units will also be required to automatically access low power modes and be shipped with those modes enabled.

 A specific test should be developed by the Standards Australia Working Group under ME-008, based on ANSI/ASHRAE Standard 32.1–2004.

 The proposed MEPS levels shall be equiva lent to the ENERGY STAR criteria, as amended December 2004.

 A category of products shall be established as “high effici ency” products th at shall be equivalent to the higher efficiency tier in ENERGY STAR requirements.

3.3.5 Rebate Programs

Several rebate programs for beverage vendi ng machines are offered by local utilities, including Austin Energy, Avista Utilities, Conne cticut Light and Power, Efficiency Vermont, Puget Sound Electricity, San Diego Gas and Electric , Seattle City Light, and Southern California Edison.

The majority of rebate programs offered by the previous organiza tions involve a cash incentive for installing an energy-saving machine sensor control system. This device uses a motion detector and a time clock to shut off th e lighting and compressor in refrigerated vending machines and the entire snack machine when th e machines are not being used, particularly overnight. These controllers are “s mart” and operate to ensure that the beverage is cold, yet can save 20 percent to 50 percent on th e electricity used by these machines. The most widely used device is the VendingMiser, created by USA Technologies.

Table 3.3.3 summarizes some of the rebates available for BVMs:

3-9 bvm_nopr_tsd_chapter03.docmTable 3.3.3 Beverage Vending Machine Rebate Programs Utility Condition Rebate/Incentive Austin Energy Installation of VendingMiser Free VendingMiser (listed as $200 value)
Avista Utilities Installation of Machine Sensor Control System $90/unit Connecticut Light and Power Installation of Machine Sensor Control System $75/unit Efficiency Vermont Installation of Machine Sensor Control System $45/unit Puget Sound Electricity Installation of VendingMiser $80/unit San Diego Gas and Electric Installation of M achine Sensor Control System $90-125/unit Seattle City Light Installation of VendingMiser $80/unit Southern California Edison Installation of Machine Sensor Control System $90/unit Installation upgrade of shaded-pole evaporator fan motor to either permanent split capacitor (PSC) motors or electronically commutated motors (ECMs) $20/m otor

3.4 MARKET ASSESSMENT

The following market assessment identifies th e manufacturer trade association, domestic manufacturers of beverage ve nding machines, manufacturer mark et share; defines equipment classes; provides energy savings potential data; presents barriers to efficiency improvements; and summarizes market performance data.

3.4.1 Trade Associations

The National Automatic Merchandising Associa tion (NAMA) is the trade association for manufacturers of refrigerated beverage ve nding machines, and the American Beverage Association (ABA) is the trade a ssociation for the bottlers and sy rup companies in the beverage industry.

NAMA was founded in 1933 and serves all food and refreshment vending, coffee service, and food management industries. Members of the organization include service companies, equipment manufacturers, and suppliers. 9

T he technical department of NAMA was found ed in 1957 to ensure the vending industry serve public health by dispensing safe and w holesome food. To this end, NAMA provides various technical servic es to group members:

 Establishment of voluntary “Standard for San itary Design and Construction of Food and Beverage Vending Machines”

 Inspection of vending machines for complia nce with Food and Drug Administration and NAMA requirements;

 Certification of companies and individua l vending machines as “NAMA” approved, which may be advertised as a service mark;

 Training for technicians on effectiv e vending machine maintenance; and

 Industry Publications on technical services, health, and safety.

3-10 bvm_nopr_tsd_chapter03.docmABA is the trade association for America’s non -alcoholic refreshment be verage industry. It is closely linked with the refr igerated beverage vending machine industry in so far as ABA’s members (e.g., Pepsi-Cola Co., Coca-Cola Co.) are the largest purch asers of BVMs. The association provides a forum for the members to discuss common issues and serves as an industry liaison to the government and public. It offers technical and non-technical services to its members. In addition, ABA projects a unified voice for the non- alcoholic refreshment beverage industry in legisl ative and regulatory matters. 10

3 .4.2 Manufacturers and Market Share

T he three manufacturers that hold a majority of domestic market share for beverage vending machines are listed below.

 Crane Merchandising/Dixie-Narco, Inc.

 Royal Vendors, Inc.

 Sanden-Vendo America

O ther manufacturers of refrigerated bevera ge vending machines are listed below.

 Seaga Manufacturing

 Automatic Merchandising Systems

 Multi-Max Distributed Vending System

 Distributed Vending Company

 Edina Technical Products

 Jofemar USA

 Wittern Group

Table 3.4.1 summarizes relevant market and pe rforma nce data for beverage vending machines. Values are presented for installed base, annual shipments, equipment lifetime, unit energy consumption, and national aggregate energy consumption.

Table 3.4.1 Beverage Vending Machine Census and Energy Use Data

Census and Energy Use Data S ource of the Data

I nstalled Base (units):

 Cans 2,400,000

 Bottles 1,125,000

 Other 186,000

Total 3,711,000 Arthur D. Little, Inc. (ADL) (1996) 11

Annual Shipments (units): 342,000 Appliance Magazine 51 st Annual Report (2003 values)

Unit Energy Consumption: 3,000 kWh/year ADL (1996) 11

3-11 bvm_nopr_tsd_chapter03.docm3, 64 4 kWh/year E-SOURCE (1996) 1

A DL (1996) 11 Primary Annual Energy Consumption: 0.121 Quad

3.4.2.1 Small Businesses

DOE is considering the possibility that sma ll businesses would be particularly impacted by the promulgation of energy conservation standards for beverage vending machines. The Small Business Administration (SBA) defines sm all business manufacturing enterprises for automatic vending machine manufacturing as those having 500 employees or fewer. 12 SBA lists small business size standards for i ndustries as they are described in the North American Industry Classification System (NAICS). The size standard for an industry is the largest that a for-profit concern can be in that industry and still qualify as a small business for Federal Government programs. These size standards are generally ex pressed in terms of the average annual receipts or the average employment of a firm. For be verage vending machines, the size standard is matched to NAICS code 333311, Automatic Vending Machine Manufacturing, and is 500 employees.

DOE will study in detail the potential imp acts on these small businesses during the manufacturer impact analysis, which will be c onducted as a part of the notice of proposed rulemaking analysis. Table 3.4.2 lists the small business beverage vending machine

m anufacturers that DOE has identified.

Table 3.4.2 Small Business Manufacturers of Beverage Vending Machines
Seag a Manufa cturing, Inc. Automatic Merchandising Systems, Inc. Royal Vendors, Inc.
Multi-Max Vending Wittern Group Edina T echnical Products

3.4.3 Equipment Classes

Bev erage vending machines can be divided in to different equipment classes categorized by physical characteristics that affect the efficiency of the equipment. Most of these characteristics affect the merchandise that the equipment cools and vends, and how that merchandise is accessed by the customer. Key p hysical characteristics ar e the door type (glassfront or solid-front) and the vendi ble capacity (or the refrigerated volume) of the machine. The energy consumption of the refrigerated bevera ge vending machine also depends on where the machine is placed (indoors or outdoors) and the ambient conditions (temperature and relative humidity) to which it is exposed. DOE proposed the following four equipment classes in its Framework document, defined according to equipment use designation and physical characteristics such as door type:

Beverage vending machines for indoor use only: (a) Class A Machine (glass front or fully cooled) (b) Class B Machine (any beverage vending machine)

3-12 bvm_nopr_tsd_chapter03.docmBeverage vending machines for indoor/outdoor use: (a) Class A Machine (glass-fr ont or fully-cooled) (b) Class B Machine (closed-front or zone-cooled)

How ever, based on comments made by the stakeholders at the Framework public meeting, and data showing that there are few Cl ass A machines installe d outdoors (because of safety and vandalism reasons) and hardly any Cla ss B machines that are certified for indoor use only, DOE has decided to use the following two equipment classes of beverage vending machines:

(a) Class A Machine (glass front or fully cooled) (b) Class B Machine (any beverage vending m achine not considered to be Class A)

DOE has reduced the number of equipment cl asses from four to two. Energy usage has been proven to be unaffected by machine location. Research has also proven there are not any locations in the U.S. whose annual temperature gradient would warrant a separate equipment class to differentiate indoor a nd outdoor machines. Therefore, DOE is using the following two equipment class descriptions:

 Class A beverage vending mach ines manufactured today typi cally utilize a transparent (glass or transparent polymer) front and generally use “she lf-style” vending mechanisms. Because the next-to-be-vended product is visi ble to the consumer and any product can be selected by the consumer off of the shelf, a ll bottled or canned beve rage containers are necessarily enclosed within the refrigerated volume.

 Class B beverage vending machines in use today generally have an opaque front and utilize a “stack-style” vending mechanism. The next-to-be vende d bottled or canned beverage is not generally visibl e to the consumer and is located at the bottom of a vertical stack of beverage containers. Any products visible to a consumer in this class of machines are for display purposes only.

3.4.4 Typical Refrigeration System

Vending machines use self-contained refriger ation systems consisting of a compressor, evaporator, condenser, and expa nsion device. In Class A machines, the compressor and condenser are typically located in a compartment to one side of the refrigerated cabinet. In Class B machines, the compressor and condenser are typical ly located in the bottom portion of the unit, between the ground and the refrigerated cabinet. Refrigerant is pipe d through the expansion device to an evaporator inside the refrigerated cabinet. The compressor consumes by far the most energy in the vending mach ine. Laboratory test results of a single Class A and a Class B machine for a 24-hour test with ambient conditio ns at 90°F and 65 percent relative humidity indicate the compressor accounts for 65 to 75 percent of the total energy consumed (see Table 3.4.3 ). 13 Oversized single-speed compressors are commonly used to provide excess cooling capacity to pull down product temperatur es quickly after the machine is restocked. A condenser fan operates concurrently with compressor cycling and uses less than 10 percent of the total energy. The evaporator fan runs continuous ly to distribute air through the refrigerated

3-13 bvm_nopr_tsd_chapter03.docmcabinet and consumes about 8 percent of total m achine energy. Lighting systems usually remain on the entire time a vending machine is plugged in. Different lighting systems are used, depending on the machine, but usually consume 5 to 20 percent of the total energy. Dispensing mechanisms operate intermittently, whenever a pr oduct is purchased, and therefore do not use a significant amount of energy (1 to 3 per cent) compared to other components.

Table 3.4.3 Energy Use by Component for Typical Vending Machines Component Class A Machine [%] Class B Machine [%] Compressor 76 65 Condenser Fan 9 7 Evaporator Fan 8 8 Lighting 4 19 Money-Handling Mechanism 3 1

H eat enters the refrigerated section of the cabinet by the following methods:

 Released by the evaporator fan motor

 Released by the lighting (g lass-front units only)

 Conduction through the insulated envelope

 Infiltration through imperfections in constructio n such as cracks in the box or improperly sealed delivery doors

 Radiation through the glass fr ont (glass-front units only)

 Product restocking (warm product placed into th e machine must be cooled to acceptable temperature).

A vending machine’s refrigeration system is highly vulnerable to changes in its surroundings. Cooling load can be increased by high ambient temperatures, which raise head pressure, resulting in loss of refrigeration eff ect and increased compression ratio. High ambient temperatures also increase conducti on, radiation, and sens ible infiltration loads. High humidity increases latent infiltration load, and can cause ex treme ice build-up on the evaporator coil. This may severely restrict airflow through the unit an d minimize the amount of heat absorbed by the refrigerant. Exposure to sunlight greatly increases heat gain in to the refrigerated space through direct solar radiation (especially in glass-front machines) raises the sol-air temperature of the cabinet exterior, and increases c onduction load. Exposure to high- intensity lighting fixtures can have a similar (but smaller) effect.

Condenser coils are usually located in the bot tom of the machine, with air intakes at ground level. Because coils often get dirty and clogged, condensers often lose their heat rejection effectiveness, which reduces refrig eration capacity and increases compressor power use. Steel security cages are often placed aroun d machines, especially when they are outdoors. These cages trap heat rejected by the condenser as it exits the rear of the machine. Trapped heat increases the inlet air temperature at the condenser, causing operations at higher condensing temperatures.

3-14 bvm_nopr_tsd_chapter03.docmThe site owner can improve vending machin e efficiency by: keeping machines in cool/shaded locations to minimize sun exposure, keeping condenser coils clean, and installing a controller that will shift the unit to low power mode based on low traffic or low sales rate.

3.4.5 Energy Savings Potential

In the Priority Setting Document (October 2005), 14 DOE estimated that the cumulative energy savings potential in the year s 2010–2035 ranges from 0.48 to 1.11 quads for beverage vending machines, depending on the energy efficiency technologies implemented, as shown in Table 3.4.4.

Table 3.4.4 Potential Energy Savings Esti mates for Beverage Vending Machines

Technology/Standard Level Energy Savings Potential (%) Annual Energy Savings Potential (quads) Energy Saving Potential (2010- 2035), (quads) Source

Combination (high efficiency compressor and brushless DC evaporator fan motor) 28 0.034 0.71 ADL (1996)

<2 Years Payback (ECM for evaporator fans and high efficiency compressor) 32 0.039 0.85 ADL (1996)

<5 Years Payback (add high efficiency condenser fan motor) 42 0.051 1.11 ADL (1996)

ENERGY STAR Tier 1 18 0.022 0.48 ENERGY STAR website ENERGY STAR Tier 2 33 0.040 0.87 ENERGY STAR website
CEC January 1, 2006 18 0.022 0.48 CEC Appliance Efficiency Regulations
CEC January 1, 2007 18 CEC Appliance Efficiency Regulations 0.022 0.48

S ource: “FY2006 Appliance Standards Program Priority-Setting Summary Report and Actions Proposed,” Beverage Vending Machines – Energy Saving Potential Estimates, DOE (October 2005).

T he technologies shown in the above table are described below.

 Combination of technologies: This is a theoretic al “combination” of two technologies presented in the ADL 1996 report—a high effici ency compressor and a brushless directcurrent (DC) evaporator fan motor. Both the compressor and the evaporator fan motor are relatively simple to change and could be deployed on a retrofit basis. The energy savings potential for vending machines wa s shown at 28 percent of annual energy consumption, with simple payback periods of about 1 year for the high efficiency compressor and about two years for the brushless DC evaporator fan motor.

 Less than two-year payback technologies: The 1996 ADL report details beverage vending machine designs including energy effici ent technologies that individually have either a less than two-year or a less than five-year payback period. A combination of high efficiency compressor, electronic lighti ng ballast and an ECM evaporator fan motor was shown to have a payback of less than tw o years. These energy efficient technologies gave an energy savings potential of 32 percent.

3-15 bvm_nopr_tsd_chapter03.docm Less than five-year payback technologies: A combination of variable-speed compressor, electronic lighting ballast, an ECM evaporat or fan motor and improved insulation was shown to have a payback of less than five years, giving a 42 percent total energy savings potential.

ENERGY STAR and CEC do not specify a specific technology but require manufacturers to design equipment to meet performance specification levels.

3.4.6 Barriers to Efficiency Improvements

A split-incentive system is where bottling companies or distributors purchase nearly all vending machines from the equipment manufacturer s but do not pay the util ity bills associated with their operation. The split-incentive syst em, described in a 2002 report by the American Council for an Energy Efficient Economy 15 is the largest barrier to improved efficiency for beverage vending machines. In general, the bottl ers or distributors place the machines at the end-user’s site for free in exchange for the exclus ive right to service the machine and/or to split the coin-box revenues with the end user. In al most all cases, the end user, not the bottler or distributor, pays the electric bi ll. Consequently, most bottling companies and distributors are concerned primarily with first costs and have litt le interest in energy efficiency because they do not pay the utility bills. Acco rdingly, manufacturers do not include efficiency measures in their designs if the measures increase initial cost, despite the short payback periods.

In short, barriers to adoption of energy efficiency technolog ies include a focus by equipment purchaser on first costs, lack of awar eness of the availability of energy efficiency improvements, and a lack of in centive since the equipment purchas er generally does not pay the utility bills.

3.4.7 Market Performance Data

DOE conducted a survey of existing beverage vending machines and compiled a performance database. The primary source of in formation for the database was equipment data sheets that were publicly available on the CEC and ENERGY STAR websites. 16
, 17 From these data sheets, equipment data such as capacity and daily energy consumption (DEC), according to the test procedure in ANSI/AS HRAE Standard 32.1–2004, are known. Figure 3.4.1
, Figure 3.4.3, Figure 3.4.4 and Figure 3.4.5 show DEC values as a functi on of vendible capacity, while Figure 3.4.2 shows DEC values as a function of re frigerated vo lume (in cubic feet).

3-16 bvm_nopr_tsd_chapter03.docmFigure 3.4.1 Market Performance Data for California Energy Commission Qualified Class A Equipment Class

Figure 3.4.2 Market Performance Data for California Energy Commission Qualified Class A Equipment Class

3-17 bvm_nopr_tsd_chapter03.docmFigure 3.4.3 Market Performance Data for California Energy Commission Qualified Class B Equipment Class

Figure 3.4.4 Market Performance Data fo r ENERGY STAR Class A Equipment Class

3-18 bvm_nopr_tsd_chapter03.docmFigure 3.4.5 Market Performance Data fo r ENERGY STAR Class B Equipment Class

3.5 TECHNOLOGY ASSESSMENT

The purpose of the technology assessment is to develop a preliminar y list of technologies that could potentially be used to improve the efficiency of beverage vending machines.

3.5.1 Higher Efficiency Lighting

Refri gerated beverage vending machines often include lighting to illuminate the contents, an exterior sign, or both. Class A machines typically include inte rior lighting to illuminate the merchandise on display, while Class B machines have an illuminated sign on the exterior. Higher efficiency lighting leads to energy savings in two ways: le ss energy is used directly for lighting and, in those units with lighting intern al to the refrigerated space, less heat energy is dissipated into the refr igerated volume by the lamp and ballast.

Efficiency in lighting is commonly measured as efficacy (lumens/watt), or the quantity of light output (measured in lumens) per electrical energy input (measured in watts). Recently, the vending machine industry has been moving toward the use of T-8 fluorescent lighting in all cases, which is substantially more efficacious than T-12 lighting, and is predominantly used with electronic ballasts, which are more efficient than magnetic ballasts commonly used in T-12 lighting.

An eve n more recent trend is the use of light emitting diode (LED) technology. Although LEDs are currently less efficacious than fluorescent technology, they are more directional than linear fluorescent bulbs, allowing for comparable illumination with less total wattage. There have been recent advancements in LED efficacy as well as the adoption of LED technology by Seaga Manufacturing in their new Premium Collection of refr igerated beverage vending

3-19 bvm_nopr_tsd_chapter03.docm18 These predicted trends have been proven true since the ANOPR. See chapter 5 of the TSD for a detailed description of the changes made to LED prices and specifi cations for the NOPR.

3.5.2 Higher Efficiency Lighting Ballasts

Most illuminated beverage vending machin es use fluorescent lighting with magnetic ballasts, which use inductance to modulate power flow to fluorescent lamps. Magnetic ballasts have significant electrical resistance losses. El ectronic ballasts use solid state electronics to modulate power provided to fluorescent lamps. Electronic ballasts, which convert power at high frequency, have lower electrical resistance losses compared to ma gnetic ballasts which operate at line frequency. In addition, fluorescent lamps ope rate more efficiently at the higher frequency provided by electronic ballasts. In addition to the direct redu ctions in electrical power consumption, heat generated by the lighting and the lighting ballast contribut e to the heat load. By increasing ballast efficiency, th e compressor load is also reduced.

3.5.3 Higher Efficiency Evaporator Fan Motors

Evaporator fan motors move air across the evap orator coil and typically run at one speed. Manufacturers match the motor size and blade to th e evaporator coil to meet the expected load under most conditions. Higher e fficiency evaporator fan motors reduce energy consumption by requiring less electrical power to generate motor shaft output power.

Electric motors operate based on the inter action between a field magnet and a magnetic rotor. In a brushed motor, the field magnets are permanent magnets and the rotor is an electromagnet; the situation is re versed in a brushless motor. The electromagnetic interactions between these two magnets cause the rotor to rotate.

The simplest type of electric motor—the single-phase electric motor—suffers from a serious shortcoming. Single-phase motors only produce a rotating magnetic field when the rotor is rotating, and simply powering the electromagne t is therefore not sufficient to start such a motor. One of the most significant differences be tween different types of single-phase motors is the way in which they handl e this start-up problem.

Nearl y all inexpensive fan motors are of e ither the shaded-pole or the permanent split capacitor (PSC) variety, and the same is most lik ely true for standard BVM fan motors (fan motors not marketed as “high efficiency”). In both cases, the electroma gnet consists of windings of electrical wire through which current is driven. In a shaded -pole motor, a portion of these windings is “shaded” by a copper loop. The interactions between the magnetic field generated by the shaded portion and that generated by th e un-shaded portion induce rotation when the motor is powered. The imbalance between the shaded and un-shaded portions of the magnet remains throughout operation. As a result, shaded-pol e motors are inefficient, with typical motor efficiencies less than 20 percent. 19 Shaded-pole motors are, however, electrically simple and inexpensive.

3-20 bvm_nopr_tsd_chapter03.docmIn a PSC motor, a smaller, start-up winding is present in addition to the main winding. The start-up winding is electricall y connected in parallel with the main winding and in series with a capacitor. At start-up, the interactions between the magnetic field generated by the start up winding and that generated by the main windi ng induce rotation. Because of the capacitor, however, the current to the start- up winding is cut off as the motor reaches steady state. Because of this, PSC motors are more energy efficient than their shaded-pole counterparts, with motor efficiencies ranging from 50 to 70 percent. Like shaded-pole motors, PSC motors are produced in large quantities and are relatively inexpensive. 20 BVM equipment fan energy efficiency can be substantially improved by replacing shaded-pol e motors, in the models that use them, with PSC motors.

A thir d type of electric motor, the electr onically commutated permanent magnet (ECM) motor (also known as a brushless permanent magnet motor), is more energy-efficient than either shaded-pole or PSC motors. ECM motors, whic h are sold in high volumes, are three-phase electric motors with efficiencies even greater than PSC motors. However, ECM motors can weigh about twice as much and are more expensive than equivalent PSC motors.

3.5.4 Evaporator Fan Controls

Typically, evaporator fan contro ls are programmed such that th e evaporator fan runs at a 100 percent duty cycle to circulat e cold air at all times and to prevent frost build up on the evaporator fan coil. However, refrigerated beve rage vending machine utility can be maintained with a lower duty cycle. This could be accomp lished through software reprogramming and the addition of relays and switches.

3.5.5 Higher Efficiency Evaporator Fan Blades

High efficiency evaporator fan blades, or tangential evaporator fans, move air more efficiently, yielding energy consum ption savings by reducing the re quired fan shaft power. The evaporator fans typically used in beverage ve nding machines have sh eet metal blades. The blades are typically supplied by a fan blade manufacturer and mounted to the motor by the equipment manufacturer. These fan blades are not optimized for refrigerated beverage vending machines. Evaporator fans may have lower e fficiencies due to the higher required pressure drops, for which sheet metal fans are not well suited. Required fan shaft power could be reduced if the fan blades were optimized for each given application.

Tangential fans also provide an opport unity to decrease equipment energy consumption. 21 Tangential fans utilize a vortex builder to generate a uniform airflow over a large surface. This makes them better suited to evaporator and condenser fans, which need to distribute airflow over a large coil surface area. A single long tangential fa n can meet the airflow requirements for an entire refrigerated cabinet , while requiring a single high efficiency fan
motor.

3.5.6 Improved Evaporator Design

The evaporator is a refrigerant-to-air heat exchanger composed of metals with high thermal conductivity such as aluminum and coppe r. It is responsible for evaporating and superheating the entering refriger ant liquid-vapor mixture while ex tracting heat from the air in

3-21 bvm_nopr_tsd_chapter03.docmthe refrigerated space. The internal heat-exc hanging surfaces in contact with refrigerant are commonly referred to as “refri gerant-side” while the external heat-exchanging surfaces in contact with the air are re ferred to as “air-side.”

Depending on the requirements of the equipment, the evaporator will have a discharge air temperature (DAT) that can be up to 10  F colder than the desired te mperature of the product in the refrigerated space. Because a temperature diffe rence is necessary to dr ive heat from the air into the refrigerant, the saturated evaporator temp erature (SET) must be considerably colder than the DAT. The magnitude of this driving force is directly related to the total refrigeration load and the thermal characteristics of the evaporator as shown in Equation 3.2:

( )

ln CAT DAT
CAT SET T Q
UA LM
DA T SET 

          Eq. 3.2



where Q is the tota l refrigeration load in British thermal units per hour (Btu/h), U

is the heat transfer coeffici ent of the evaporator in Btu/  F/square foot (ft 2)

, A is the area of the evaporator in ft 2

, CAT is the case air temperature, and Δ T LM is the log mean temperature difference of the coil in  F.

Incre asing the area of the coil decreases the necessary Δ T LM and therefore decreases the SET. This results in an increased compressor energy efficiency ratio (EER) and lower compressor energy consumption.

Enhancements to the refrigerant-side surface area of the evaporat or typically include rifled or diamond-pattern tubing and increased number of tube passes. Enhancements to the air-side surface area include increased fin pitch (decreased fin spacing), fin patterns (wavy or zig-zag), and increased numb ers of tube passes.

Incre asing the overall size of the coil in one or more dimensions without changing other aspects of the coil is another way to increase th e area. However, most applications limit the amount of coil size increase. Most approaches to increasing the evaporator surface area also result in an increase in required fan motor power and an increase in refrigerant pressure drop.

3.5.7 Low Pressure Differential Evaporators

Decreasing the air-side pressure drop of an evaporator coil allows for the use of lowerpower evaporator fan motors. This requires reducing restrictions to the flow of air across the coil such as high fin pitch, and high numbers of tube passes. Large spaces between fins and tubes also reduce frost “bridging,” wh ich can completely block airflow through portions of the coil.

3.5.8 Improved or Thicker Insulation

Eithe r increasing the insulation thickness or reducing insulation thermal conductivity will reduce the energy consumption of beverage vend ing machines. Typical insulation thickness for

3-22 bvm_nopr_tsd_chapter03.docmImproved-technology polyurethane foam in sulation has a reduced conductivity, which reduces the heat load. The improvement is due mainly to the formati on of smaller air cells within the foam insulation structure and better ce ll-size consistency. Use of better foam reduces the heat load, assuming no wall thickness change.

The im portance of refrigerated volume suggest s that technologies that allow reduction in insulation thickness while maintaining thermal re sistivity (R-value) would be of interest. Vacuum panels could provide such performance. Vacuum panels are airti ght panels sealed with glass or plastic, which are evacuat ed to eliminate a conduction pat h. They are generally filled with supporting powder that prevents collapse of th e external seal. Much work needs to be done to demonstrate the reliability of vacuum panels to show that they will perform for many years without leaking and losing their insulating value. In addition, current-technology vacuum panels do not provide the necessary structural rigidity be tween sheet metal panels that is possible with foamed-in-place polyurethane insulation.

3.5.9 Improved Glass Pack (for Class A machines)

For Class A machines, the glass front allows consumers to view the merchandise they can purchase. However, the glass front (referred to as a glass pack) allows heat transfer due to radiation and glass packs typically are not good insulators of heat compared to solid walls. Thus any improvements made to the glass pack to re duce radiation and conduction heat loads will also reduce compressor power. Glass pack improvements can be accomplished in several ways: addition of spectrally selective coatings (referred to as low-E coatings), adding panes of glass, using argon instead of air as a filler gas, and sw itching from an aluminum frame to a vinyl frame.

3.5.10 Defrost Mechanism

As the air in the refrigerated space is coole d, water vapor condenses on the surface of the evaporator coil. In refrigerators and freezers, where the evaporator coil is below 32 °F, this water freezes as it collects, forming a growing layer of frost. The frost reduces cooling performance by increasing the thermal resistance to heat transfer from the coil to the air, and by obstructing airflow. Both the method in which de frost is performed and control of the defrost cycle can lead to increased energy savings.

There are two methods available for defrosting th e evaporator coil in this case: off-cycle defrost and electric defrost. O ff-cycle defrost involves shutting o ff refrigerant flow to the coil while leaving the evaporator fan running. This method is used where cabinet air is above the freezing point of water and can be used to melt the frost. Electric defrost is used where the air temperature is not high enough to defrost the co il, and where defrost must occur quickly to prevent any significant rise in product temperatur e. Electric defrost involves melting frost by briefly turning on an electric resi stance heater, which is in contact with or near the evaporator coil.

3-23 bvm_nopr_tsd_chapter03.docm3.5.11 Thermoacoustic Refrigeration

Thermo acoustic refrigeration is a technology that uses high-amplitude sound waves in a pressurized gas to pump heat from one place to anot her. A device consisting of a series of small parallel channels, referred to as a “stack,” is fixed in place at a set location inside a resonator tube. In the case of a thermoacoustic refriger ator, external work is supplied by the standing sound wave in the resonator.

The longitudinal standing sound wave causes the gas particles to oscillate back and forth parallel to the walls of the stack. The alternat ing compression and rarefaction of the gas causes the local temperature of the gas to oscillate due to the adiabatic nature of sound waves. If the local temperature of the gas becomes higher than th at of the nearby stack wa ll, heat is transferred from the gas to the stack wall. If the local temp erature of the gas drops below that of the stack wall, heat is transferred from the wall to the gas.

Prototypes of thermoacoustic re frigerators have been demo nstrated for refrigeration applications. A prototype thermoacoustic refrig eration unit designed for an ice-cream freezer has been measured to be as efficient as the vapor compression unit it re places. This technology is expected to improve in efficiency with fu rther development of heat exchangers and other subsystems. It is also likel y that efficiency in many applications could improve because thermoacoustic refrigerators are well suited to pr oportional control, wher e the cooling capacity can be continuously controlled so that the output can be adjusted accura tely for varying load conditions. Although, this technol ogy currently does not impr ove upon the efficiencies of conventional refrigeration tec hnology, thermoacoustic refriger ation has the environmental benefit of being refrigerant-free.

3.5.12 Magnetic Refrigeration

Magnetic refrigeration utilizes the magneto -caloric effect where magneto-caloric materials like gadolinium absorb heat from their surroundings when entering a magnetic field, then reject heat to their surroundings when exiting a magnetic field. When magneto-caloric materials are circulated through ma gnetic fields and combined with heat exchangers to transfer heat, they can be used to remove heat from a refrigerated space a nd reject heat to the surroundings.

This refrigeration technology could be used in any possible applic ation where cooling, heating or power generation is used today. B ecause of the early stage of development, many technical issues need to be addressed for this technology to be commercially viable.

3.5.13 Electro-hydrodynamic Enhanced Heat Transfer

Electro-hydrodynamic (EHD) enhanced heat tran sfer is the result of applying a highvoltage electrostatic potential fiel d across a heat transfer fluid, such as a refrigerant or refrigerant mixture. The applied field destabilizes th e thermal boundary layer, thereby producing better mixing of the bulk fluid flow and increasing the net heat transfer coefficient. This procedure appears to be more effective when applie d to phase-change processes (e.g., boiling and condensation).

3-24 bvm_nopr_tsd_chapter03.docmThis ph enomenon is typically used to electr onically control the capacity of a heat exchanger by raising the applied vo ltage to increase the heat transf er. This can lead to improved efficiencies by using smaller capacity equipmen t, most of the time without EHD, and then utilizing the EHD effect during peak loads. EHD can replace, or work in conjunction with, enhanced surface heat exchangers. To use EHD, an electrical voltage (from a few volts to thousands of volts) is applied to the heat transfer device. Howe ver, because the heat transfer fluids are typically dielectric (of low electrical conductivity), even high voltages produce very little current. This low current helps keep th e power (voltage x current) and the associated energy penalty low.

3.5.14 Copper Rotor Motors

Making the critical components of an induc tion motor’s rotor (e.g., conductor bars and end rings) out of copper instead of aluminum, which is the curre nt practice, improves the energy efficiency of the motor. The gr eater electrical conductiv ity of copper results in lower resistance heating losses in the rotor and thus lower losse s in the motor. Further improvements in the design and fabrication of copper motors, such as optimization of the steel laminations, could further increase the efficiency of copper motors over aluminum motors.

3.5.15 Higher Efficiency Compressors

Several technologies exist to increase th e efficiency of beverage vending machine compressors. High efficiency reciprocating a nd scroll compressors, sometimes incorporating variable-speed motors, all have higher efficienci es than the traditional reciprocating compressors commonly used in beverage vending machines.

Scroll compressors compress gas in a fundame ntally different manner from traditional compressors—between two spirals, one fixed and one rotating. High efficiency reciprocating compressors are as efficient, or more efficien t, than scroll compressors. However, some drawbacks exist including noise , cost and reliability, compared to scroll compressors.

3.5.16 Improved Condenser Design

Like the evaporator, the condens er is a refrigerant-to-air heat exchanger composed of metals with high thermal conductivity such as al uminum and copper. It is responsible for condensing and sub-cooling the entering refrige rant vapor while rejecting heat from the refrigerant to the ambient air.

Depend ing on the requirements of the equipmen t, the condenser will have a saturated condenser temperature (SCT) that is about 10 °F warmer than the ambient air. As with evaporator coils, increasing the area of the condenser coil will decrease the necessary Δ T LM of the coil and therefore decrease the SC T, resulting in increased compressor efficiency (increased EER).

Enhancements to the refrigerant-side surf ace area of the condenser typically include rifled or diamond-pattern tubing and increased number of tube passe s. Enhancements to the airside surface area include increa sed fin pitch (decreased fin sp acing), fin patterns (wavy or zigzag), and increased numbers of tube passes.

3-25 bvm_nopr_tsd_chapter03.docmIncrea sing the overall size of the coil in one or more dimensions without changing other aspects of the coil is another way to increase th e area. However, most applications limit the amount of coil size increase in order to main tain overall equipment dimensions. Most approaches to increasing the condenser surface area also result in an increase in required fan motor power and an increase in refrigerant pressure drop.

3.5.17 Higher Efficiency Condenser Fan Motors

Condenser fan motors are responsible for moving air across the condenser coil and typically run at one speed. The manufacturer will match the motor size and blade to the evaporator coil to meet the expected load on the case under most conditi ons. Higher efficiency condenser fan motors reduce energy consumption by requiring less electrical power to generate motor shaft output power. Condenser fan motors are generally of the same size and type as evaporator fan motors. See section 3.5.3 for a discussion of higher efficiency evaporator fan motor technology.

3.5.18 Higher Efficiency Condenser Fan Blades

High efficiency condenser fan blades, or tangential condenser fans, move air more efficiently, yielding energy consum ption savings by reducing the re quired fan shaft power. The condenser fans typically used in refrigeration equipment have sheet metal blades. The blades are typically supplied by a fan blade manufacturer and mounted to the motor by the equipment manufacturer. These fan blades are not optimi zed for beverage vending machines. Required fan shaft power could be reduced if the fan blades were optimized for each given application.

Tangential fan also provide an opportunity to decrease refrigeration equipment energy consumption. Tangential fans utilize a vortex builder to generate a uniform airflow over a large surface. This makes them ideal for evaporator and condenser fans that need to distribute airflow over a large surface area. A singl e long tangential fan can meet the airflow requirements for an entire condenser, while only requiri ng one high efficiency fan motor.

3.5.19 Higher Efficiency Expansion Valves

Expansion valves are refrigerant metering de vices whose purpose is to control the amount of refrigerant flowing to the evaporator coil. In doing so, they simultaneously decrease the temperature and pressure of the refrigerant, cr eating a cold liquid-vapor mixture. The low temperature of the refrigerant leaving the expansi on valve creates the driving force to move heat out of the refrigerated space and into the evaporator.

The mo st basic type of expansion device is a capillary tube, which is used in beverage vending machines. The capillary tube is a long, thin piece of pipe that creates a pressure drop in the refrigerant through frictional losses. Capillary tubes must be sized to the particular application and cannot adjust for variations in load or ambient operating conditions. They are often oversized for worst-case conditions, and ther efore may operate at reduced efficiency during normal operation. However, using an alternate technology such as a thermostatic expansion valve (i.e., TXV) or an electronic expansion va lve (i.e., EEV) will likely not provide significant energy savings over a properly sized capil lary tube under steady-state conditions.

3-26 bvm_nopr_tsd_chapter03.docm3. 5.20 Variable-Speed Compressors

Va riable-speed compressors are implemented through the use of an electronic control on the compressor motor, which allows the motor to operate at different speeds. Variable-speed compressors reduce energy c onsumption in three ways b :

1. When refrigerant flow is reduced duri ng part-load operation, the condenser and evaporator (designed for full flow conditi ons) are more effective and thus more efficient. Temperature drops decrease, resu lting in reduced pressure rise across the compressor, which also improves efficiency.

2. Close matching of load eliminates the cycling that occurs with single-stage compressors. Maintaining a constant pressure is more efficient because losses at higher pressure rise are greater th an gains at lower pressure rise.

3. Duri ng the off-cycle, the pressure in the system equilibrates. At the intermediate pressure, refrigerant vapor condenses in the cold evaporator rather than the condenser. Essentially, some of the heat reje ction load is rejected to the evaporator during this time, reducing overall system performance. Variable-speed operation would eliminate or significantly redu ce compressor off-time and the related inefficiencies.

3.5.21 Liquid Suction Heat Exchangers

The purpose of a liquid suction heat exchange r is to further cool the flow of liquid refrigerant entering the expansion valve using the flow of gaseous re frigerant leaving the evaporator, thus providing addi tional sub-cooling for the ente ring liquid by super-heating the exiting suction vapor. Hotter suction vapor is de sirable because it is less susceptible to heat gains in the return piping to the compressor, provides an additional margin of safety as superheated vapor for compressor operation (since any liquid en tering the compressor may cause damage). Additional sub-cooling of the liquid entering the expansion valve is desirable because it provides additional cooling capacity in the evaporator. However, the compressor work is increased because the suction vapor has greater enthalpy. In addition, the possibility of compressor overheating brought on by the combina tion of increased compressor work and hotter vapor limits the use of this method in some situ ations. The possibility for these problems and the potential gains of liquid suction heat exchangers depend on several factors, including evaporator temperature, type of refrigeran t used, and system pressures.

3.5.22 Condenser Fan Motor Controllers

Condenser fan motor controllers allow fan mo tors to run at variable speed, to match changing conditions in the vending machine. Matching the fan speed to all conditions improves coil performance. This allows the refrigerati on system to run more efficiently at different ambient humidity and temperature levels. Howe ver, under steady-state conditions, there is no energy savings benefit with c ondenser fan motor controllers.

b Variable-speed compressors typica lly increase efficiency over a broad op erating range but do not inherently increase maximum efficiency at the compressor rating point.

3-27 bvm_nopr_tsd_chapter03.docm3-28 bvm_nopr_tsd_chapter03.docmREFERENCES

1 Houghton, D. 1996. “Refrigerated Vending Ma chines – Overlooked Devices Hold Opportunities for Efficiency, New Services ”, Tech Update TU-96-7, E Source, Inc., Boulder, Colorado

2 American Society of Heating, Refriger ating, and Air-Conditioning Engineers, Inc. (ASHRAE) Handbook “2006 Refrigerat ion”, ASHRAE, Atlanta, GA.

3 Underwriters Laboratorie s (UL) Standard 541-2003, Refrigerated Vending Machines

.

4 American Society of Heating, Refrig erating, and Air-Conditioning Engineers, Inc.(ASHRAE), 2004. Methods of Testing for Rating Ve nding Machines for Bottled, Canned, and Other Sealed Beverages, ANSI/ASHRAE 32.1-2004

.

5 ANSI/Association of Home Appliance Manufacturers (AHAM). 2004. Energy, Performance and Capacity of Household Re frigerators, Refrigerator-Freezers and Freezers. ANSI/AHAM HRF-1-2004.

6 Energy Star 2007, ENERGY STAR ® Program Requirements for Refrigerated Beverage Vending Machines Eligibility Criteria Version 2.0 <

< http://www.energystar.gov/index.cfm?c=vending_machines.pr_vending_machines>

7 California Energy Commission. 2006. “Applia nce Efficiency Regulations,” CEC-400- 2006-002 Rev. 2[1]

8 Report No: 2008/10 Minimum Energy Performance Standard: Refrigerated Beverage Vending Machines , National Appliance and Equipment Energy Efficiency Program (NAEEEC). < http://www.energyrati ng.gov.au/library/pubs/200810-ris-vending.pdf>

9 National Automatic Merchandising Association, <http://www.vending.org>

10 American Beverage Association, < http://www.ameribev.org/index.aspx?

11 Arthur D. Little, Inc., Energy Savings Potential for Commercial Refrigeration Equipment . U.S. Department of Energy, June 1996.

12 Small Business Administration, November 2006, http://www.sba.gov/gopher/Financial-Assistance /Size-Standards/sizetablestandards.txt.

13 Faramarzi, R. and Mitchell, S. 2006. “N ext Generation Vending Machine”, Southern California Edison report.

3-29 bvm_nopr_tsd_chapter03.docm3-30 bvm_nopr_tsd_chapter03.docm 14 U.S. Department of Energy. 2005. FY2006 A ppliance Standards Program PrioritySetting Summary Report and Actions Propos ed,” Beverage Vending Machines – Energy Saving Potential Estimates, DOE (October 2005)

15 Nadel, S. 2002. “Packaged commercial refr igeration equipment: A briefing report for

program planners and implementers”, Repor t Number A022, American Council for an Energy-Efficient Economy, Washington, D.C.

16 California Energy Commission, Appliances Database (Last Accessed July 11, 2007) <http://www.energy.ca.gov/appliances /appliance/excel_based_files/>

17 ENERGY STAR, New Machine Product List, (Last Accessed July 11, 2007) <http://www.energystar.gov/ia/products/prod_lists/vending_prod_list.pdf>

18 Lighting Resource Center, LRC, Rame sh Raghavan and Nadarajah Narendran, Refrigerated Display Case Lighting with LEDs , Lighting Research Center, Rensselaer Polytechnic Institute, 2002 Solid State Lighti ng II: proceeding of the Society of PhotoOptical Instrumentation Engineers.

19 “Single-phase Electric Motors,” November 2006, http://www.iprocessmart.com/leeson/ leeson_singlephase_article.htm.

20 “Technical Support Document for Energy Conservation Standards for Room Air Conditioners,” U.S. DOE, September 1997.

21 “Investigation of Energy-Efficient Superm arket Display Cases,” Oak Ridge National Laboratory, December 2004.