study on the potential for hydrocarbon replacements report dr. w. keith snelson national research...

United Nations Environment ProgrammeDivision of Technology, Industry and EconomicsEnergy and OzonAction UnitOzonAction Programme

Multilateral Fund for the Implementation of the Montreal Protocol

Study on the Potential for Hydrocarbon Replacementsin Existing Domestic and Small Commercial Refrigeration Appliances

UNEP

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Disclaimer

The United Nations Environment Programme (UNEP), the authors and the reviewers of this document and their employeesdo not endorse the performance, worker safety, or environmental acceptability of any of the technical or policy optionsdescribed in this document.

While the information contained herein is believed to be accurate, it is of necessity presented in a summary and generalfashion. The decision to implement one of the options presented in this document requires careful consideration of a widerange of situation-specific parameters, many of which may not be addressed by this document. Responsibility for thisdecision and all its resulting impacts rests exclusively with the individual or entity choosing to implement the option.

UNEP, the authors, the reviewers and their employees do not make any warranty or representation, either expressed orimplied, with respect to its accuracy, completeness or utility; nor do they assume any liability for events resulting from theuse of, reliance upon, any information, material or procedure described herein, including but not limited to any claimsregarding health, safety, environmental effects, efficacy, performance, or cost made by the source of information.

The reviewers listed in this document have reviewed one or more interim drafts of this document, but have not reviewedthis final version. These reviewers are not responsible for any errors which may be present in this document or for anyeffects which may result from such errors.

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All product names and trademarks used in this document belong to their respective companies.

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Any or all parts of this document may be reproduced without prior or written consent, as long as the reproduced portion isattributed to UNEP.

UNITED NATIONS PUBLICATIONISBN 92-807-1765-0

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A Message from UNEP’s Executive Director

One of the major challenges posed to the Montreal Protocol is to protect the stratospheric ozone layerwhile ensuring that developing countries are not economically disadvantaged during their transition tonew technologies that do not rely on ozone depleting substances (ODS). This is particularly applicableto the refrigeration sector, which accounts for the largest share of ODS consumption in developingcountries and touches virtually every person’s life, directly or indirectly.

Today, developing countries face another unique challenge. What should those nations do with themillions of existing domestic and commercial refrigerators and freezers that use ozone-depleting CFC-12 refrigerants? Unlike the practice in industrialized countries, the replacement of refrigeratorsand freezers due to old age or fashion is not common in developing countries. For some families andbusinesses, refrigerators are life-long possessions. Accordingly, repair, rather than replacement, is thehabit. Can those appliance owners in developing countries continue to use their existing refrigeratorsand freezers but at the same time protect the ozone layer by retrofitting the equipment to use non-CFCrefrigerants?

Under the leadership of UNEP DTIE’s OzonAction Programme under the Multilateral Fund for theImplementation of the Montreal Protocol, and with the generous support of Environment Canada,GTZ/Proklima, National Research Council Canada, the Netherland’s Ministry of DevelopmentCooperation, the Swiss Agency for Development and Cooperation (SDC) and the Swiss Agency forEnvironment, Forests and Landscape (SAEFL), technologists and environmentalists around the worldresearched possible answers to this question. Their findings of their global studies and field experiencesare presented in this publication, the Study on the Potential for Hydrocarbon Replacements in ExistingDomestic and Small Commercial Refrigeration Appliances.

The study addresses retrofitting of existing appliances with hydrocarbons, which apart from protectingthe ozone layer, also have the advantage of not contributing to climate change as they are not greenhousegases (unlike HFCs). The study is intended to provide background to decision-makers in developingcountries who must weigh the positive and negative aspects of this retrofitting option.

UNEP believes that this study contributes to addressing the unique challenge faced by developingcountries in phasing-out CFCs and protecting the ozone layer.

I am particularly pleased that this study is being released in 1999, a year whichmarks the beginning of the Montreal Protocol control measures by developingcountries.

Klaus TöpferUnited Nations Under-Secretary-General

and Executive Director of UNEP

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Acknowledgements

This document was produced by UNEP Division of Technology, Industry and Economics (UNEP TIE) as partof its OzonAction Programme under the Multilateral Fund.

The project was managed by:

Ms. Jacqueline Aloisi de LarderelDirector, UNEP TIE

Mr. Rajendra ShendeChief, UNEP TIE Energy and OzonAction Unit

Mr. Steve GormanRegional Network Manager, UNEP TIE OzonAction Programme

Mr. James S. CurlinInformation Officer, UNEP TIE OzonAction Programme

And

Dr. W. Keith SnelsonNational Research Council Canada

Synthesis Report Dr. W. Keith Snelson

National Research Council Canada

Desk SurveyProf. Radhey S. Agarwal

Co-Chair, UNEP Refrigeration TechnicalOption Committee Indian Institute ofTechnology (New Delhi)

Ir. Martien JanssenMember, UNEP Refrigeration Technical OptionCommittee Re/genT BV (The Netherlands)

Workshop Report Mr. Samuel Hess

INFRAS Consulting Group for Policy Analysisand Implementation

Mr. Nikolas SchallConsultant

Dr. Othmar SchwankINFRAS Consulting Group for Policy Analysisand Implementation

Costa Rica Country StudyMr. Ebel Dijkstra andMs. Marja Tummers

Ecozone (Netherlands)Ms. Marcela Velázquez

CEGESTI (Costa Rica)

Cuba Country StudyDr. Nelso Espinosa Pina

Oficina Técnica de Ozono (Cuba)Mr. Ebel Dijkstra and Ms. Marja Tummers

Ecozone (Netherlands)Ms. Marcela Vel·zquez

CEGESTI (Costa Rica)

Indonesia Country StudyMr Manfred Egger

Swisscontact - SMEPMr. Ebel Dijkstra and Ms. Marja Tummers

Ecozone (Netherlands)

The document was written by:

Quality review of specific sections of this document was done by:

Dr. Lambert KuijpersCo-chair, UNEP Technology and Economic Assessment Panel

UNEP TIE wishes to thank all contributors and their employees for helping to make this document possible,as well as the generous support of Environment Canada, GTZ/Proklima, National Research Council Canada,the Netherland’s Ministry of Development Co-operation, the Swiss Agency for Development andCooperation (SDC) and the Swiss Agency for Environment, Forests and Landscape (SAEFL).

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TABLE OF CONTENTS

Page

PREFACE............................................................................................................ 7

SYNTHESIS REPORT ......................................................................................... 9

PART I - DESK SURVEY ..................................................................................... 271 Introduction .................................................................................................... 312 Acceptability of a retrofit refrigerant for domestic and small

commercial refrigeration systems ................................................................. 323 Refrigerant property data ............................................................................. 344 Material compatibility and refrigerant/lubricant interaction .................... 395 Appliance performance ................................................................................. 426 Reliability ........................................................................................................ 507 Safety aspects of hydrocarbon refrigerants ................................................. 538 Regulations and standards ............................................................................ 589 Availability and costs of hydrocarbon refrigerants ..................................... 6210 Servicing and drop-in conversion of R-12 appliances

to hydrocarbon blends ................................................................................... 6411 Conclusions and recommendations .............................................................. 66List of References .................................................................................................. 69

PART II - COUNTRY SPECIFIC SURVEYS............................................................ 85

Indonesia ......................................................................................................... 85Introduction .......................................................................................................... 891 Overview phase-out of ODS in Indonesia ..................................................... 912 Methodology................................................................................................... 923 The proposed alternatives.............................................................................. 934 Could Hydrocarbons work.............................................................................. 945 Results UNEP Study ......................................................................................... 956 General observations and recommendations............................................... 114ANNEXES ............................................................................................................... 117

Costa Rica ........................................................................................................ 1631 Overview phase-out of ODS in Costa Rica .................................................... 1672 Methodology................................................................................................... 1683 The proposed alternatives.............................................................................. 1694 Could Hydrocarbons work.............................................................................. 1705 Results UNEP Study ......................................................................................... 1716 General observations and recommendations............................................... 185ANNEXES ............................................................................................................... 187

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Cuba ................................................................................................................. 229Introduction ........................................................................................................... 2331 Overview phase-out of ODS in Cuba............................................................. 2342 Political background ....................................................................................... 2353 The Ministry of Environment ......................................................................... 2364 The development of hydrocarbon refrigerant in Cuba............................... 2375 Methodology................................................................................................... 2386 Results Unep Study.......................................................................................... 2397 General observations and recommendations............................................... 252ANNEXES ............................................................................................................... 255

PART III - WORKSHOP REPORT ......................................................................... 2831 Introduction..................................................................................................... 2872 Results of the Workshop ................................................................................ 2893 Conclusions ...................................................................................................... 292ANNEXES ................................................................................................................ 295

About the UNEP DTIE OzonAction Programme ....................................................... 367

About the UNEP Division of Technology, Industry and Economics .......................... 368

Table of contents

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Preface

The possibility of using hydrocarbons (HCs) to retrofit existing CFC-based domestic and smallcommercial refrigeration applicances (e.g. refrigerators, freezers, small display cases, soft drink and icecream coolers) has been informally considered and applied for some years as a possible option to helpdeveloping countries meet their obligations under the Montreal Protocol. Until now, this issue has notbeen substantially investigated and documented in the context of the Multilateral Fund for theImplementation of the Montreal Protocol.

With only anecdotal stories and isolated data available, Article 5 countries, developed countries andother interested parties within the Multilateral Fund community have had little on which to basepotential future decisions about the viability of this technical option. This study helps close theinformation gap to some extent.

The study is designed to help policy-makers make informed judgements about retrofitting existingdomestic and small commercial appliances with HCs. It provides key information: conclusions a crucialinternational forum on this subject (the Workshop Report), existing technical information collectedfrom diverse sources (the Desk Survey), newly collected data from the field (the three Country Studies),and a “big picture” report that ties each of these elements together (the Synthesis Report). It alsoidentifies additional work that needs to be done before making decisions.

Although developed countries, bilateral agencies and refrigeration sector experts and others should findthe data and conclusions useful and thought-provoking, the study will be of particular interest to lowvolume ODS-consuming countries (LVCs). Like mid- and large-sized Article 5 countries, LVCs havecommited to reducing and eliminating CFCs and other ozone depleting substances (ODS) under theMontreal Protocol. However unlike their larger bretheren, LVCs have more limited options available inthe short term to reduce CFC consumption in order to meet their 1999 freeze and subsequent reductioncommitments under the Protocol. Retrofitting with hydrocarbons is one approach that could help themmeet these targets.

The need for this study emerged during late 1996 at meetings of the Regional Networks of ODSOfficers, during which UNEP received repeated requests for information on such issues as the technicaland economic feasibility of equipment conversion, safety and liability aspects, servicing requirements,and training needs. The study was approved and funded as part of UNEP’s 1997 Work Programmeunder the Multilateral Fund with additional financial support from Environment Canada,GTZ/Proklima, National Research Council Canada, the Netherland’s Ministry of Development Co-operation, the Swiss Agency for Development and Cooperation (SDC) and the Swiss Agency forEnvironment, Forests and Landscape (SAEFL).

In the interest of disseminating this information as widely as possible, UNEP is also making this reportavailable free-of-charge on its website at http://www.unepie.org/ozonaction.html.

Preface

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Study on the Potential for Hydrocarbon Replacements

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W. Keith Snelson

National Research Council Canada

Study on the Potential

for Hydrocarbon Replacements

in Domestic and Small

Commercial Refrigeration Appliances

Synthesis Report

January 1999

UNEP

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1. INTRODUCTION

In late 1996 interested delegates from Article 5, non-Article 5, as well as all the Implementing Agenciesattended a meeting in Costa Rica to discuss the possibilities of retrofitting used domestic and smallcommercial appliances with hydrocarbons (HCs) to replace CFCs. During this and follow-up meetingsof the networks of ODS officers a strong interest was expressed by all participants in the viability of thistechnology as a possible option to assist in complying with the requirements of the Montreal Protocol.The main target for this technology would be the Low Volume Consuming countries (LVCs) that havelimited options available in the short term to reduce CFC consumption for various appliances includingrefrigerators, freezers, small display cases, soft drink and ice cream coolers, etc. Any consideration ofthis option leads to the question whether there is sufficient information available to enable the policymakers and others in those countries to make informed decisions on the use of HCs for suchapplications. In an attempt to respond to requests especially from national ozone unit officers and othersfor more information on issues such as technical and economic feasibility of equipment conversion,safety and liability aspects, servicing requirements, training needs, etc., the United NationsEnvironment Programme - Division of Technology, Industry and Economics (UNEP DTIE) proposeda Study on this topic in its 1997 Work Programme and approval was obtained from the ExecutiveCommittee of the Multilateral Fund.

The Study was sponsored by UNEP with additional support from the Ministry of Development Co-operation in the Netherlands government. The National Research Council of Canada (NRC) wasselected to provide overall project management services for the Study. As the Project Manager, theindependent stature of NRC was perceived as being able to add credibility and provide an objective andunbiased approach to the final synthesis reporting process. The initial study work was conducted duringJuly/August 1997 and preliminary reports covering the various sections were prepared by thecontractors as input to a Workshop held in Montreal in September 1997. The Workshop provided aforum for dissemination and discussion of the issues among ozone officers, technicians, and policy-level officials from Article 5 countries as well as experts from Article 2 countries and others. (TheMontreal Workshop was funded, managed and reported separately and was not included under theproject management tasks in the Terms of Reference for the Study.) Follow-up work continued after theWorkshop and revised draft reports were completed and reviewed. Most of the study reports weresubsequently finalized in late 1997. However release of the Cuban country report was delayed at therequest of the government authorities to enable the Cuban Technical Ozone Office to provide its owninput which was received in April 1998.

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2. PURPOSE AND SCOPE

The overall objective of the Study was to review and assess the information and knowledge available(and identify areas where the level of understanding needs to be improved) on the feasibility of usingvarious HCs as replacements for CFCs, especially in existing domestic and small scale commercialrefrigeration equipment. With the focus on applications in Article 5 countries and the potential foreligibility of financing from the Montreal Protocol Multilateral Fund (MF) the Study was also intendedto address the issues that need to be considered by the MF in its efforts to assess whether the technologyis proven, environmentally viable, and represents a cost-effective option.

The Study was divided into two parts:

(1) A Desk Survey (Part 1) to review all existing literature available on experiences with HCs whenused as replacements in existing domestic/small commercial refrigeration systems. The objectiveof the literature review was to establish whether sufficient information was available to accept HCsas possible drop-in or retrofit refrigerants in such applications. This task was shared by Re/genTBV (Mr. Martien Janssen) and the Indian Institute of Technology (Prof. R.S. Agarwal).

(2) A Country Specific Survey (Part 2) to assess the particular experiences in three selected countriesof Costa Rica, Cuba and Indonesia, where various HC (and LPG) technology related programs inthis particular application area were known to have been active in recent years. This part of theStudy was undertaken by Ecozone BV (Mr. Ebel Dijkstra and Ms. Marja Tummers), with supportfrom Swisscontact-SMEP (Mr. Manfred Egger) and Cegesti (Ms. Marcela Velázquez). Additionalinput for Cuba was subsequently provided by the Oficina Técnica de Ozono (Dr. Nelson EspinosaPena).


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3. STRATEGY

3.1 Part 1 - Desk Survey

The approach taken was to consult with several manufacturers of small refrigeration appliances todetermine what information would be required to qualify any proposed new refrigerant for suchapplication. This type of analysis has already been undertaken by equipment manufacturers for otherCFC alternatives now commercially available. The procedure leads to the definition of eight criteria forwhich information is required before any new refrigerant can be accepted for service:

• Refrigerant properties data• Material compatibility and refrigerant/lubricant interaction• Appliance performance• Reliability• Safety of refrigerant and equipment• Standards and regulations• Availability and costs • Servicing procedure

Each of the defined criteria were considered relative to the specific hydrocarbon replacementapplication being studied, and a thorough international literature search of all possible sources ofinformation was conducted. In all over 230 references were identified in the study. For each criterionconsidered a summary of the status quo of the knowledge base was presented.

By analyzing the contents of the various references found against a checklist of requirements as definedin the list of criteria, a matrix was prepared highlighting the information which is available andidentifying where gaps exist in the knowledge base. Corresponding recommendations were made onwhether the level of know-how is appropriate and some conclusions drawn concerning the applicabilityof hydrocarbons as service refrigerants and as a possible replacement option in this context.

3.2 Part 2 - Country Specific Survey

For the case studies in the three countries identified the objective was to gather information onexperiences in the areas of technical and economic feasibility, safety related issues, country regulationsand liability aspects, energy efficiency, evaluation of practices, training facilities for service staff,availability of servicing equipment, consumer awareness, and public perceptions of the technology.

The methodology used in each case was to develop a detailed questionnaire intended to provide in-depthcoverage of the above issues, and conduct interviews with key stakeholding groups and individuals inthose countries. Specifically the survey was targeted at ozone unit officers, government agencies,refrigerator supply companies and their service departments, local refrigeration entrepreneurs,training/education organizations, etc. The questionnaires were sub-divided into five categories coveringenvironmental, economic, social, technical, and regulatory and liability aspects. For each country theinformation obtained from all sources and contacts was compiled into five report sub-sections each

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containing a corresponding set of observations, followed at the end by some general conclusions andrecommendations.

In the case of Indonesia a total of 51 individuals were interviewed representing 25 organizations,comprising government ministries and agencies, refrigeration equipment manufacturers/retailers,service workshops, technical training centres, etc. Since HC refrigerants are relatively new in Indonesia,most respondents were not able to answer all questions and some were not relevant, but thequestionnaire served as a satisfactory framework for discussion in the various interviews.

In Costa Rica a series of 12 interviews were performed, covering a representative cross-section of thoseinvolved in the potential introduction of HC refrigerants in that country. The group interviewed includedindividuals from government, refrigerator manufacturing, refrigeration equipment distribution, serviceand maintenance workshops, user industry, and university/training institutes.

In Cuba some of the planned interviews were subsequently cancelled, but eventually 11 organizationswere visited and 25 representatives mostly from government agencies were questioned. Very significantand extensive experiences with retrofitting of a special LPG blend were discussed in some of theseinterviews. Initial reporting of this information was completed by the contractor but not released,pending review and authorization from Cuban government officials. Eventually the contents of the samereport were accepted with minor changes.


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4. MAJOR FINDINGS

4.1 Part 1 - Desk Survey

Most of the literature discussed in the Desk Survey pertains to blends of R-290/R-600a (propane andisobutane), since these fluids can be composed to form blends having a very similar cooling capacityand pressure/temperature conditions to that of CFC-12 and are therefore most suitable for the domesticrefrigerator working fluid replacement scenario.

• Refrigerant Properties Data

The thermodynamic and thermophysical properties data for R-290 and R-600a as singlecomponent refrigerants are all well established over many years, and with the increasing use ofthese substances as refrigerant mixtures the corresponding properties of the blends of theserefrigerants are also well documented. Sophisticated computer software is also readily available toprovide complete and accurate properties data for pure hydrocarbons and their blends.

Upper and lower flammability limits by volume in air and corresponding auto ignitiontemperatures are well known for R-290, R-600a and typical blends. Sufficient data is also availableon the toxicity levels, exposure limits, and corresponding safety classifications of these refrigerants.

In hydrocarbons the presence of contaminants can lead to problems and, depending on the level,may cause damage to compressors as well as adversely affecting system refrigeration capacitiesand efficiencies. This is particularly an issue when using LPG which often contains water and othercontaminants. Impurities within the refrigerant blend concentrations can also affect capacities andefficiencies, especially at higher deviations from the specified composition. The purityrequirements for R-290 and R-600a and limits on types of contaminants have been clearly specifiedby refrigerant manufacturers, and the same spedifications would apply for the blends. Howeverthere is little information available on the effects on refrigeration systems of deviating from thespecified purity levels.

It is clear that adequate information is available on pure HCs and blends includingthermodynamic and thermophysical properties, flammability and toxicity data,contaminant/purity levels, and environmental data (ODP, GWP, etc.)

• Material Compatibility and Refrigerant/Lubricant Interaction

Some information is available to indicate good compatibility of both propane and isobutane withcommonly used refrigeration system materials including steel, brass, copper, aluminium, andvarious elastomers and desiccants. An equal or better compatibility is claimed compared to CFC-12 and mineral oil systems. Further extensive but unreported experience with materials mustclearly exist among equipment manufacturers involved in the production of new domesticrefrigerators designed to operate (especially) with isobutane.

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In any refrigeration system some lubricating oil circulates around with the refrigerant through thevarious system components. The effects of the oil content are strongly related to the ability of therefrigerant to be dissolved into the lubricant. Higher levels of refrigerant solubility lead to markedreductions in viscosity of the refrigerant/lubricant solution, which is beneficial for oil return to thecompressor but may be detrimental for bearing lubrication. In the case of hydrocarbons theavailable experimental data seems to be somewhat conflicting on the solubility effects of propaneand isobutane in mineral oil when compared to CFC-12 in mineral oil. For the most part it isreported that the hydrocarbons are more soluble than CFC-12, causing a reduction of viscosity inthe refrigerant/oil mixture, and therefore higher viscosity oil is recommended to compensate.However there is also contradictory evidence which indicates that higher levels of viscosity areexperienced with hydrocarbons and mineral oil, leading to corresponding recommendations forusing a lower or similar viscosity oil. In other retrofit investigations the original mineral oil wasused successfully with the hydrocarbon blend replacement, implying that the viscosity of thesolution did not change significantly and provided satisfactory operation.

In summary although publications on detailed analysis of materials compatibility arerelatively limited, it is concluded that propane and isobutane in combination with mineraloils are compatible with commonly used refrigeration system materials. Howeverinformation on the solubility of hydrocarbons in mineral oil and the effects on viscosity issomewhat contradictory, and further investigation is needed to clarify these issues.

• Appliance Performance

There are abundant references covering the performance of HC blends (especiallypropane/isobutane) applied in domestic refrigerators designed for CFC-12. Many investigatorshave conducted theoretical and experimental studies to determine the effects of substitutionparticularly on energy consumption. The studies have investigated single temperature and two-temperature appliances and cover drop-in and various levels of optimization including capillarytube size variation, refrigerant charge adjustments, and different blend compositions.

Various researchers have conducted measurements on the changes in energy consumption for anunmodified single temperature refrigerator using a R-290/R600a blend (50%/50%wt.) as a drop-inreplacement for CFC-12. Reported results vary from seeing little or no change up to an increase ofover 20% in energy usage. In some cases substantial performance improvements were observed byincreasing capillary tube length, and varying the amounts of charge and mixture composition.Minimal information is reported on the effects on cooling capacity, but there are some reports oflonger pull down times indicating reductions in capacity.

Several reports indicated that the zeotropic refrigerant blend is unsuitable for application in two-temperature appliances due to the separation of the two fluids causing unacceptably highrefrigerator temperatures and leading to elevated energy consumption levels (up to 30% higher).However this temperature glide effect problem has been addressed in some cases by redesign of theunit to accommodate the two-temperature capability within a single evaporator.

In the case of small commercial refrigeration appliances conversion to hydrocarbons is simplerthan for domestic refrigerators since most are single temperature appliances. One company has


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reported achieving an energy efficiency increase of 15-20% after conversion of its line of displaycases to HC blends from HFC-134a. The only modification made was to seal any electricalcomponents that could possibly cause a spark. Other reports of retrofitting small commercial unitswith the R-290/R-600a blend indicate that energy consumption is about the same or even less thanwith CFC-12, after making changes to the capillary tube length.

Sufficient information is available on energy consumption to indicate that application ofHC blends can yield small improvements depending on the level of system modifications(e.g. adjustment of charge, capillary tube length, etc.), but can also result in increases upto 30% for certain types of appliances (e.g. two-temperature compartments with separateevaporators). However with regard to cooling capacity, there is clearly a lack ofinformation on the effects of hydrocarbon replacement. The latter is an important missingelement since it relates directly to the ability of the refrigerator to maintain specifiedproduct storage temperatures at maximum ambient temperature conditions.

• Reliability

Some lifetime tests on compressors and domestic appliances with HC mixture refrigerants havebeen reported, and in general a good reliability is demonstrated. Specifically for the compressorstested, observations indicated no problems with wear, sludge and acid formation, copper plating,and deposits. Before and after analysis of refrigerant and lubricant also showed no degradation.

An important consideration for long-term reliability is the ability of the compressor to start andoperate at low or high voltages while exposed to low or high ambient temperatures. No data isreported on this topic for HC mixtures operating under retrofit conditions.

There are no significant amounts of data available on reliability testing of domesticrefrigeration equipment converted to run on propane/isobutane.

• Safety of refrigerant and equipment

Hydrocarbon blends are flammable in concentrations in air between 2% and 9% by volume, andpossibly a fire can start if a combustible mixture of fluid and air is present within those limits andsimultaneously an ignition source of sufficient intensity is present. Given the concern over thepotential of flammability under such conditions it is essential to adopt adequate safety measures inthe system when retrofitting or servicing with these refrigerants. The importance of the need forsafety is emphasized by the large number of relevant publications reviewed in the Study.Approaches vary from that of ignoring the safety problem altogether (due to the small chargeinvolved) to the other extreme of considering all possible events leading to hazardous situationswith corresponding detailed risk analyses. There are many references which emphasize thatappliances using flammable refrigerants need to be designed to meet very high technical standardsof safety. Systematic approaches have been developed for the safe handling, transport, and storageof hydrocarbon refrigerants. Depending on the safety classification selected for a particularappliance various levels of protection may be adopted, such as evaporators foamed into the cabinetwall and explosion proof electrical equipment (thermostat and lighting) located outside the cabinet.With new product the adoption of such measures is achievable and the corresponding risk

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assessment indicates a very low probability of a fire-event. Furthermore it is mentioned thatattitudes towards the use of a small charge of flammable refrigerant (less than 100 grams) mightnot be a major concern in some developing countries where much larger quantities of flammablematerial are often utilized for domestic cooking purposes on a daily basis.

Risk assessment is an essential methodology used to address safety aspects of an operation, identifythe possibility of accidents, analyze the consequences, and assess the related risk probability.Results from several studies have indicated that the risk associated with the use of flammablerefrigerants in domestic appliances is reasonably low. However there is some experimentalevidence reported and demonstrated in videotapes, which shows that flammable conditions canexist in the vicinity of a refrigerator. In this series of tests quantities of propane/isobutane wereallowed to leak under controlled conditions into the space around the appliance and then a sparkwas introduced to cause ignition. These tests indicated that the heavier gases can accumulate atground level and lead to concentrations of refrigerant in air within the flammability range evenunder moderate ventilation conditions.

The issue of consumer safety as it relates to liability is briefly addressed. In the case of any safetyrelated problems with new equipment liability normally rests with the system’s manufacturers, butthe important question of who carries legal responsibility when an appliance is converted to operatewith flammable refrigerants has not been resolved.

It is concluded that sufficient safety related information is available on product design andmodification practices for the application of hydrocarbons in domestic refrigerationsystems, and this kind of information is being incorporated into amendments of someexisting standards. However more conversion details are required on specific products,i.e. what modifications must be applied, when and how?

• Standards and regulations

Many investigators have conducted overview studies on regulations and standards relevant to theuse of HC blends as service refrigerants, but it is concluded that at present there is no singlestandard available anywhere in the world that addresses all the safety related issues. However thereare some national and international standards which discuss the mechanical and electrical safetyrequirements of domestic refrigeration appliances, and a few of these do include safety aspects offlammable refrigerants. In general most of the developing countries do not have any standardswhich include flammable refrigerants.

The European standard EN378 is currently under revision to include the use of flammablerefrigerants, and when adopted it is expected to supersede British standard BS4434 and Germanstandard DIN7003. In its revised form standard EN378 will classify refrigerants according to theirpotential hazards. For each refrigerant (including HCs and blends) a maximum practical limit isspecified in terms of allowable charge per unit of volume in a humanly occupied space. Additional limits are placed on maximum allowable charge according to the type of occupancy ofthe space. This standard also forbids the location of any ignition sources in the vicinity of systemscontaining flammable refrigerants. Elsewhere, other standards such as ANSI/ASHRAE Standard15 in the United States bans the use of flammable refrigerants except in experimental and


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industrial applications. However the U.S. EPA will consider approval of the use of hydrocarbonrefrigerants under its SNAP program if the application meets the requirement of a nationallyrecognized safety standard. The UL-250 standard for household refrigerators and freezers now permits the use of flammable refrigerant in amounts, which would limit leaks to less than 40grams. In the international standards area IEC 335-2-24 (safety standard for householdrefrigerators) has been revised and now allows the use of flammable refrigerants in quantities up to150 grams.

A joint IEC/ISO working group has also been established to develop requirements pertaining to theuse of flammable refrigerants, and ultimately the measures approved will be incorporated asamendments to safety standards IEC 335-2-40 (heat pumps and air conditioners) as well as ISO5149 (mechanical refrigeration systems used for cooling and heating). It is anticipated thatcorresponding European, U.S., and Japanese standards will eventually harmonize with these ISOand IEC standards.

It is clear from the level of activities reported in this area that there are many national andinternational standards now under review, and that revisions involving the adoption offlammable refrigerants are being considered. Whether the new provisions adopted bysuch standards will be broad enough to apply to modification of existing equipment is animportant issue. As regards the existence of any rules and regulations permitting theretrofit of refrigeration appliances with hydrocarbons this can only be determined forspecific cases by examination of regulations at the national level. Similarly in the case ofstorage and transport of flammable refrigerants, where any laws do exist they aretypically governed by local authorities.

• Availability and costs

Refrigerant grade high purity hydrocarbons including propane and isobutane can be obtained fromrefinery distillation processes and are abundantly available from international manufacturersmostly located in Europe. Some manufacturers are extending their supply networks to servedeveloping countries. In some of those countries it may be possible to obtain refrigerant gradehydrocarbons as a by-product from local petroleum refineries or gas processing industries.

Costs of HC refrigerants are dependent on quantities being purchased, purity levels, andvarious other market driven factors. However the data suggests that prices will be similarto or lower than current CFC-12 cost.

• Servicing procedure

Safe servicing practices for appliances using hydrocarbon refrigerants are similar to the servicingprocedures followed for CFC-12 based units, except that additional safety precautions are neededto avoid any risk of flammability. The necessary detailed safety measures have been widelyreported, covering the safe practices to be followed, guidelines for workmanship, and the specialtools and equipment required. The need for proper training of service technicians in this area isemphasized in many publications.

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As regards conversion of refrigeration appliances to operate with hydrocarbons, a systematic step-by-step procedure has been developed and documented for retrofitting of domestic refrigeratorsfrom CFC-12 to hydrocarbon blends. In this procedure it is suggested that any sparking electricalcomponents need to be replaced, re-positioned or enclosed when an appliance is converted.However in some cases the additional costs associated with making these and other retrofit safetymeasures may be prohibitive, depending on local economic conditions.

It is concluded that some useful practical guidelines and manuals have been developed forsafe servicing of domestic refrigeration equipment using flammable refrigerants, as well asconversion procedures for such appliances to operate with hydrocarbon blends. Howeverthis information needs to be improved with respect to emphasis on safety measures, and tobe more specific about which products can be converted and under what conditions.

4.2 Part 2 - Country Specific Survey

• Indonesia

So far the use of HCs in domestic refrigeration appliances in Indonesia has been limited to a smallnumber of entrepreneurs who have attended training workshops conducted by Swisscontact andEcozone to promote this technology. As a result there are less than ten service centres in the countrythat are currently applying the technology.

From these limited experiences reported there appears to be a good acceptance of HC technologyby those entrepreneurs and technicians who are involved in its application. No before and afterconversion performance measurements have been done for domestic refrigeration appliances. Noaccidents or problems are reported except for some misapplied refrigerant blend chargingtechniques. Apparently safety issues related to flammability are not a serious concern torefrigeration technicians working with HCs. This attitude is influenced by the widespreadhousehold use for cooking purposes of LPG in 12 kg cylinders, as compared to the small charge ofless than 100 g used in typical refrigerators. There are no laws, rules, or regulations applied to theuse of HCs as refrigerants, and no general agreement on what body would be responsible foraccepting any liability.

With an impending government ban in Indonesia on future import of CFCs all seven of thecountries’ refrigerator manufacturers are in the process of converting their production lines fromCFC-12 to R-134a (with Multilateral Fund support). Therefore it appears likely that ultimately R-134a will become more readily accessible throughout the country for domestic refrigeration retrofitapplications as well as new production. In the case of existing systems however the choice ofreplacement refrigerant is driven by market forces and the use of HCs could become financiallyattractive as an alternative to CFC-12 if a sufficient cost advantage develops.

• Costa Rica

Experience here is also limited to those organizations that have been trained on HC technologiesduring projects involving Swisscontact, Ecozone, and others. The total number of entrepreneurs


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with access to imported HCs and to the technology is 43, out of an estimated total of 2,500 serviceworkshops existing throughout the country. Those who have used the technology in refrigerationsystem conversions consider it to be a useful option since the procedure is simple to follow and requires no hardware changes. No accidents are reported. There is no conclusive information available on the real performance of the HC refrigerant since observations from severalsources are conflicting on energy efficiencies, compressor pull down times, and producttemperatures.

Refrigeration service technicians are generally well trained, many having graduated from nationaltraining institutes, and therefore the introduction of HC technology on a broader scale withstructured training programs would not present any technical difficulties. Some of those questionedon the viability of hydrocarbons expressed the opinion that it is a good solution only if it isaccompanied by a strong training program and safety regulations. There are no regulations in thecountry that control the use of refrigerants or refrigerant technologies and practices. This being thecase there is no clear direction on which organizations or persons should be legally responsible inthe case of an accident or a problem in the performance of the equipment.

Currently CFC-12 is still abundantly available in Costa Rica and the price is very low which makesit difficult to introduce alternatives to this refrigerant. However if the shipping costs of the importedHCs are reduced or if the local refinery is able to produce a suitable blend of HCs with the requiredlevel of purity, then hydrocarbon refrigerants could compete in the market with CFC-12 and maybe used more extensively as replacements.

• Cuba

Cuba is committed to complying with the Montreal Protocol ODS phase out requirements asdefined for Article 5 countries, and accordingly in 1998 the government there will legislate a banon importation of CFCs. However with the collapse of support from the former USSR in the early1990s the Cuban economy has experienced serious financial problems. With insufficient foreigncurrency being generated and a continuing trade embargo from the U.S., the import of basic goodsand materials was greatly reduced. This also affected the availability of refrigerants and created theneed to search for an acceptable, low cost, readily available alternative that could be adapted fordomestic refrigeration purposes.

The search led researchers at the Universidad de Oriente in Santiago de Cuba to develop ahydrocarbon blend LB-12, based on LPG produced at a local oil refinery and consisting of anunknown composition of propane, iso-butane, and n-butane. Starting in 1992 this development wassupported by the Government of Cuba, and the Cuban Ozone Technical Office has indicatedrecently that annual usage of LB-12 amounts to about 50 tonnes and that 175,000 domesticrefrigerators and 5,000 small commercial units are now successfully operating with LB-12 withoutany accidents reported. (This is approaching 10% of the estimated total number of refrigeratorsexisting in Cuba.) A limited amount of research has been conducted at the Universidad de Orienteon performance comparison of domestic refrigerators before and after conversion. However noinformation was available on the results of such tests, other than remarks to indicate that the energyconsumption was lower.

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Under control of the Cuban government the existing rules and regulations concerning production,transportation, storage and use of LPG as a fuel and cooking gas are currently being reviewed andadapted to cover hydrocarbons (including LB-12) as refrigerants. The new laws will be based onnational experience as well as existing relevant British and German standards.

Throughout the country all of the 200 plus refrigerator service workshops are state owned and allare now familiar with the application of LB-12 and the safety handling procedures. The workshopsare competent to carry out such conversions in spite of sometimes difficult working conditions andlack of spare parts and equipment. The service technicians employed in the workshops have usuallyreceived training in refrigeration technology at an intermediate level technical training institute, andnew regulations coming into force will require all service workers to acquire sufficient trainingneeded to obtain a certified permit to work in refrigeration.


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5. RECOMMENDATIONS FOR FURTHER INVESTIGATIONS

Based on analysis of the refrigerant acceptability criteria matrix and practical experiences reported inSection 4, some areas of information are still missing from the knowledge base. Accordingly thefollowing tasks have been identified for future investigation, with particular emphasis on thepropane/isobutane refrigerant mixture:

• Solubility data of selected HC blends with mineral oil and the effect of solubility on viscosity ofthe lubricant is required. Possible effects on blend composition change due to component solubi-lity differences should also be investigated.

• Some comparative calorimeter performance tests taking into account temperature glide effectsshould be undertaken to measure changes in cooling capacity and efficiency which can be expec-ted after a conversion.

• More specific lifetime tests are needed under severe conditions such as very high or very lowambient temperatures combined with low or high compressor start voltage conditions.

• Detailed information on product specific modification procedures needed to minimize risk shouldbe included in guidelines to be used for adapting appliances to hydrocarbon refrigerants.

• Further improvements are required to existing training and servicing manuals to expand on safetyguidelines and focus on which types of appliance may be converted under which conditions.

• Whether specific standards are enforced by the prevailing regulations in any particular country isan issue which needs investigation at the national level, to determine if a retrofit to HC refrigerantsis prohibited by law or not.

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6. CONCLUSIONS

An important observation documented in the concluding discussion at the September 1997 MontrealWorkshop stated that “The issue of retrofitting of small refrigeration appliances with hydrocarbons is acomplex one”. The significance of this statement was clearly demonstrated from the diverse experienceswhich emerged from the various investigations in this Study. It is evidently not possible to generalizeabout the feasibility of using HCs to replace CFCs in existing domestic and small commercialrefrigeration systems. From a technical standpoint the resulting performance after conversion will bevery product specific, may certainly be acceptable in cases such as one-temperature appliances, whilein others large energy efficiency penalties and excessive compressor running times may result. Safetyissues must also be addressed and this will be country specific, dependent on attitudes and sensitivitiestowards the use of flammable refrigerants and the existence of any regulations or standards within thecountry. The first requirement is to analyze whether a product can be safely retrofitted to the use ofhydrocarbons. The level of safety measures adopted will also impact on the cost of conversion. Theavailability of sufficient numbers of adequately trained service technicians familiar with the handling ofhydrocarbon refrigerants is another requirement to be addressed on a national basis. It seems clear thenthat the issue of feasibility must be approached on a case by case basis, to consider all the prevailingconditions and establish whether there is sufficient incentive to proceed. For some countries it may beworthwhile to facilitate this decision process by developing guidelines specific to that country’sinfrastructure and targeting specific products.

With regard to the funding support criteria used by the Multilateral Fund, not all of the issues areclarified:

• From an environmental viability standpoint, HCs are natural substances with zero ODP and negli-gible GWP, and this clearly represents an improvement over CFC based equipment. As regardsother environment related issues CO2 releases may be an additional factor to be considered in caseswhere the adoption of HC refrigeration systems leads to significantly higher levels of energyconsumption. The Total Equivalent Warming Impact (TEWI) includes the impact of greenhousegas emissions due to energy consumption as well as the impact of refrigerant emissions over thelifetime of the system. Since the energy consumption component typically represents over 90% ofthe TEWI for domestic refrigerators, the energy efficiency of the system may be (environmentally)significant in situations where electrical power is derived from fossil fuel sources.

• Cost effectiveness is concerned with the price and availability of HC refrigerants, but is also rela-ted to the incremental cost of safety measures associated with conversion of refrigeration systemsto HC technology. These are country specific considerations which will be influenced by nationalpolicies on regulation of flammable refrigerants, and other factors such as possible access to localsources of suitable hydrocarbons at lower cost.

• Although there are indications that HCs could be a promising option for certain applications, thereremain some outstanding technical issues related to whether HC retrofit technology is generallyproven and these need to be further pursued. The next steps in this direction are outlined in therecommendations contained in Section 5.


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It can be concluded that this Study has assessed a broad cross-section of information andexperience related to the potential retrofit or drop-in application of HCs in small scalehermetic refrigeration systems, and although some issues are still unresolved there is sufficientevidence to indicate that this approach may be a valid option worth considering as a means ofaccelerating CFC phaseout in some developing countries.

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About the UNEP DTIE OzonAction Programme

Nations around the world are concerned about the emissions of man-made CFCs, halons, carbontrachloride, methyl chloroform, methyl bromide and other ozone-depleting substances (ODS) thathave damaged the stratospheric ozone layer a shield around the Earth which protects life fromdangerous ultraviolet radiation from the Sun. Over 167 countries have committed themselvesunder the Montreal Protocol to phase out the use and production of these substances. Recognizingthe special needs of developing countries, the Parties to the Protocol also established a MultilateralFund and appointed implementing agencies to provide technical and financial assistance to enablethe developing countries to meet their commitments under the treaty. UNEP is one of the Fund’simplementing agencies; the others are UNDP, UNIDO and the World Bank.

Since 1991, the UNEP DTIE OzonAction Programme in Paris has been strengthening the capacity ofgovernments (especially National Ozone Units) and industry in developing countries to makeinformed decisions on technology and policy options that will result in cost-effective ODS phase-out activities with minimal external intervention. The Programme accomplishes this by deliveringa range of need-based services, including:

Information ExchangeTo enable decision makers to take informed decisions on policies and investments. Information andmanagement tools already provided for developing countries include the OzonAction InformationClearinghouse (OAIC) diskette and World Wide Web site, a quarterly newsletter, sector-specifictechnical publications for identifying and selecting alternative technologies, and policy guidelines.

Training and NetworkingThat provide platforms for exchanging experiences, developing skills, and tapping the expertise ofpeers and other experts in the global ozone protection community. Training and networkworkshops build skills for implementing and managing phase-out activities, and are conducted atthe regional level (support is also extended to national activities). The Programme currentlyoperates eight regional and sub-regional Networks of ODS Officers comprising 95 countries, whichhave resulted in member countries’ taking early steps to implement the Montreal Protocol.

Country Programmes and Institutional StrengtheningThat support the development of national ODS phase-out strategies and programmes, especiallyfor low-volume ODS-consuming countries. The Programme currently assists 79 countries in thedevelopment of their Country Programmes and implements Institutional-Strengthening projectsfor 67 countries.

For more information about these services please contact:

UNEP Division of Technology, Industry and EconomicsOzonAction Programme39-43 quai André Citroën75739 Paris Cedex 15FranceEmail: [email protected]: +33 1 44 37 14 50Fax: +33 1 44 37 14 74http://www.unepie.org/ozonaction.html

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About the UNEP Division of Technology, Industry and Economics

The mission of the UNEP Division of Technology, Industry and Economics is to help decision-makersin government, local authorities, and industry develop and adopt policies and practices that: • are cleaner and safer;• make efficient use of natural resources; • ensure adequate management of chemicals; • incorporate environmental costs; • reduce pollution and risks for humans and the environment.

The UNEP Division of Technology, Industry and Economics (UNEP TIE) located in Paris, is composedof one centre and four units:

• The International Environmental Technology Centre (Osaka), which promotes the adoption anduse of environmentally sound technologies with a focus on the environmental management ofcities and freshwater basins, in developing countries and countries in transition.

• Production and Consumption (Paris), which fosters the development of cleaner and saferproduction and consumption patterns that lead to increased efficiency in the use of naturalresources and reductions in pollution.

• Chemicals (Geneva), which promotes sustainable development by catalysing global actions andbuilding national capacities for the sound management of chemicals and the improvement ofchemical safety world-wide, with a priority on Persistent Organic Pollutants (POPs) and PriorInformed Consent (PIC, jointly with FAO).

• Energy and OzonAction (Paris), which supports the phase-out of ozone depleting substances indeveloping countries and countries with economies in transition, and promotes goodmanagement practices and use of energy, with a focus on atmospheric impacts. The UNEP/RIS -Collaborating Centre on Energy and Environment supports the work of the Unit.

• Economics and Trade (Geneva), which promotes the use and application of assessment andincentive tools for environmental policy and helps improve the understanding of linkages betweentrade and environment and the role of financial institutions in promoting sustainabledevelopment.

UNEP TIE activities focus on raising awareness, improving the transfer of information, buildingcapacity, fostering technology cooperation, partnerships and transfer, improving understanding ofenvironmental impacts of trade issues, promoting integration of environmental considerationsinto economic policies, and catalysing global chemical safety.

For more information contact:

UNEP Division of Technology, Industry and Economics39-43, Quai André Citroën75739 Paris Cedex 15FranceTel: 33 1 44 37 14 50; Fax: 33 1 44 37 14 74E-mail: [email protected]; URL: http://www.unepie.org

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study on the potential for hydrocarbon replacements report dr. w. keith snelson national research...

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