ORIGINAL ARTICLE

State of play and innovations in off-grid refrigerationtechnology: lessons learned from current initiatives

Nyamolo Abagi & Yasemin Erboy Ruff &Jennifer Corry Smith & Michael Spiak

Received: 17 July 2018 /Accepted: 3 March 2019# The Author(s) 2019

Abstract Energy efficiency enables distributed off-gridrenewable energy systems—from solar home systems torenewable micro-grids—to deliver energy services thatotherwise might be economically or technically infeasi-ble in resource-constrained settings. When super-efficient appliances are used, the total cost of solar homesystems and their associated appliances can be reducedby as much as 50% (Phadke et al. 2015). The authors ofthis paper will first explore the broader interplay ofenergy access and energy efficiency for off- and weak-grid settings by sharing learnings from the Efficiency forAccess Coalition and the UK aid funded Low-EnergyInclusive Appliances (LEIA) program. To serve as aconcrete example among off-grid appliance technolo-gies, this paper will then explore the work of LEIA andother Coalition partners to accelerate cost and efficiencyimprovements in off-grid refrigeration. Refrigerationpresents significant technical challenges to off-grid en-ergy systems because of high-energy demand in

addition to the lack of consistent and comparable per-formance data to help market stakeholders make effec-tive and informed decisions about product selection. Tohelp address this knowledge gap in the market, thispaper presents the findings of a baseline product testingeffort used to establish a foundational understanding ofthe field performance of commercially available off-gridrefrigerators. The paper further explores the role ofinnovation cash prizes in catalyzing technology innova-tion and market expansion of off-grid refrigeration ana-lyzing them through the lens of the Global Lighting andEnergy Access Partnership (Global LEAP) Off-GridRefrigerator Competition.

Keywords Refrigeration . Fieldmonitoring .

Innovation . Consumer research . Off-grid

Introduction

Background

Around 1.1 billion of the world’s poorest people liveentirely without access to electricity, another billionhave only weak and unreliable access to the grid. Energypoverty depresses and delays social and economic de-velopment (Hirmer and Guthrie 2017). Increasingly,distributed clean energy technologies such as solarhome systems (SHSs) and mini-grids are making itpossible for people and businesses to access life-changing modern energy for the first time.

Energy Efficiencyhttps://doi.org/10.1007/s12053-019-09783-1

N. AbagiCLASP, Pine Tree Plaza, Kamburu Rd., Nairobi, Kenyae-mail: nabagi@clasp.ngo

Y. Erboy Ruff : J. C. Smith (*) :M. SpiakCLASP, 1401 K St. NW, Washington, DC 20005, USAe-mail: jcorry@clasp.ngo

Y. Erboy Ruffe-mail: yerboyruff@clasp.ngo

M. Spiake-mail: mspiak@clasp.ngo

While grid enhancement and extension will play animportant role in achieving universal access to energy,the International Energy Agency has estimated that off-grid SHSs and mini-grids are the most economical wayto reach around 70% of those in rural areas that are still notconnected to the grid (International Energy Agency 2017).

Super-efficient light emitting diode (LED) technology,integrated into products and services designed for low-income consumers, has played a dominant role in thedevelopment of this market. The price of off-grid solarlighting systems has dropped by 27% over the last 5 years(Off-Grid Solar Market Trends Report 2018), and themajority of the reduction is attributable to reduced solarpanel costs. However, only around one-third of the reduc-tion is due to reduced costs of the solar photovoltaictechnology itself. The rest is due to the fact that energyefficient LEDs require smaller solar modules (and batte-ries) to provide the same service (Phadke et al. 2015). Thisis illustrated with real cost data (in US dollars) in Fig. 1.1

As promising as these new technologies are, themarket penetration and level of investment seen in thehousehold solar market are currently insufficient to de-liver on the ambition of Sustainable Development Goal7 to ensure access to affordable, reliable, sustainable,and modern energy for all by 2030 (World Bank 2018).Furthermore, the energy services offered at costs

affordable to poor consumers are typically only lighting,mobile phone charging, and radios. The developmentimpacts of these products are important but limited.

The continued development of this market—andcontinued progress in energy access—is tied to im-proved availability of appropriately designed, afford-able, highly energy-efficient appliances. It is appliancesthat create and sustain demand for energy and deliverservices like refrigeration, cooling, communications,and productivity that improve the lives and incomes ofunder-served households and communities.

However, conventional appliances frequently drawtoo much energy to be useful and/or economical whencombined with off-grid energy systems and are typicallypoorly designed for such systems. Further, the combinedenergy demand of inefficient appliances often overloadsweak electrical systems, contributing to load sheddingand power outages, and undermining the gains of energysupply investment and grid extension.

Energy efficiency enables distributed off-grid renew-able energy systems—from solar home systems to mi-cro and mini-grids—to deliver energy services that oth-erwise might be economically or technically infeasiblein resource-constrained settings. When super-efficientappliances are used, the total cost of solar home systemsand their associated appliances can be reduced by asmuch as 50% (Fig. 2) (Phadke et al. 2015). Improve-ments in the efficiency and prices of off-grid appropriatetelevisions (TVs), fans, and refrigerators are expected to

1 CFL is compact fluorescent lightbulb, the most efficient lightingtechnology prior to the widespread availability of LEDs.

$10 $20 $30 $40 $50

CFL & Lead Acid Battery (2009)

CFL & Lithium Battery(2014)

LED & Lead Acid Battery(2009)

LED & Lithium Battery(2014)

LED & Lithium Battery(2016 Projection)

LED & NiMH Battery(2012)

Retail Price by Component ($US)

Light Source Battery PV Balance of System

Fig. 1 Costs of a medium-sized Pico-PV lantern (Phadke et al. 2015)

Energy Efficiency

grow. A recent study forecasted that their combinedglobal market potential to $4.7 billion/year in 2020, aninefold increase in total market value, despite lowerappliance prices (Fig. 3) (Global LEAP 2016). Howev-er, it should be noted that very little data is available onsales of appliances in off-grid markets and more data isneeded to improve the accuracy of sales forecasts.

Just as super-efficient LED technology has unlockedthe benefits of modern lighting for millions around theglobe, other appliances promise cooling, communications,mechanization, and refrigeration to millions more, withimproved outcomes for health, education, and productivityand livelihoods. Replicating this step-change in energyefficiency in other appliance segments would improvethe impact and viability of solar home systems and mini-grids, while reducing load and blackouts on weak grids.

For energy efficiency to deliver on its potential toenable greater energy access, much more data and in-formation is needed on how products perform—both inthe field and in the lab. To date, very little field testinghas been done to understand how products performacross varying geographies and use cases.2 One of thepioneering field evaluation projects for off-gridrefrigerators—implemented by the Global Lightingand Energy Access Partnership (Global LEAP)—willbe described later in this paper.

Moving from theory to practice—the Efficiencyfor Access Coalition

As discussed above, the off- and weak-grid appliancemarket remains nascent and under-resourced, with a con-tinued need for market intelligence and partnership oppor-tunities to scale sustainably. As a component of this sector-wide effort, Efficiency for Access first launched in 2015 asa year-long call to action with the aim to help move thesector towards resolving some of the challenges related tothe off- and weak-grid appliance markets. In order toimprove overall coordination and co-funding strategies,Efficiency for Access3 was then scaled up andreintroduced in January 2018 as a coalition promotingenergy efficiency as a potent catalyst in global clean energyaccess efforts, jointly coordinated by CLASP4 and EnergySaving Trust (EST).5 Currently, UKAid,6 USAID’s PowerAfrica,7 the International Finance Corporation (IFC),8 theWorld Bank Group,9 Rockefeller Foundation,10 Shell

SHS with Standard Appliances (2009)

SHS with Standard Appliances (2014)

SHS with Appropriately-Designed,

Appliances (2014)

SHS withAppropriately-Designed,

Appliances (2017)

$0 $200 $400 $600 $800 $1000 $1200

Retail Price by Component ($US)

Lights Battery PV Balance of System Appliances

Solar Home System (SHS) Purchase Price Based on Appliance Type

Fig. 2 Photovoltaic (PV) SHS costs for same level of service with different appliance packages (Phadke et al. 2015)

2 Na rayan , N . , Yin , Z . , e t a l . h t t p s : / / l i nk . sp r i nge r.com/content/pdf/10.1007%2Fs12053-018-9725-6.pdf

3 Efficiency for Access: www.efficiencyforaccess.org4 CLASP: www.clasp.ngo5 Energy Saving Trust: www.energysavingtrust.org.uk6 UK Aid: www.ukaiddirect.org/7 Power Africa: www.usaid.gov/powerafrica8 International Finance Corporation: www.ifc.org9 World Bank Group: www.worldbank.org/10 Rockefeller Foundation: www.rockefellerfoundation.org/

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Foundation,11 the Swedish development agency Sida,12

GIZ’s EnergizingDevelopment (EnDev),13GoodEnergiesFoundation,14 and DOEN Foundation15 make up the Co-alition’s Donor Roundtable.

The Coalition’s work collectively spans 19 off- andweak-grid appropriate technologies in 44 countries—amap of the Coalition donor members’ current activity isshown in Fig. 4. In particular, there is significant interestfrom participating donors in off-grid refrigeration, asrefrigerators and advanced refrigeration (e.g., cold chaintechnologies) are observed to be of active interest andinvestment across the majority of donors relative toother product categories.

Refrigeration also constitutes one of the most matureinstances of donor cooperation in the sector. An exam-ple of Coalition partners16 working together to amplify

programmatic impacts on this top product category ofnote is through the Global LEAP Awards, which are aseries of international competitions that identify theworld’s best, most energy-efficient off-grid appli-ances,17 as well as the accompanying Off-Grid Appli-ance Procurement Incentives Program,18 both of whichwill be discussed in further detail in the followingsections.

Market stimulation and field performanceassessment for off-grid refrigerators

The Global LEAPAwards

The Global LEAP Awards (Awards) are a series ofinternational competitions that assess the relativequality of products and provide the off-grid marketwith clear, actionable signals about product perfor-mance. The Awards have been designed based ona recognition prize model and recognize off-gridappliances on the basis of a range of parametersincluding price, energy efficiency, quality, and off-

11 Shell Foundation: www.shellfoundation.org/

12 Sida: www.sida.se/English/13 EnDev: https://endev.info/content/Main_Page14 Good Energies Foundation: www.goodenergies.org/15 DOEN Foundation/ Stichting DOEN: https://www.doen.nl/about-doen/transitions.htm16 Power Africa, DFID, and EnDev have all contributed to the GlobalLEAPAwards and/or RBF program.

17 Global LEAPAwards: http://globalleap.org/awards/18 Global LEAPOff-Grid Appliance Procurement Incentives Program:http://globalleap.org/incentives/

$62M$76M

$386M

$245M$221M

$1024M

$503M$1081M

$3126M

017,4$ 094,1$425$

2015 Current 2015 Potential* 2020 Potential*

TOTAL(USD, millions)

Refrigerators (15%) Fans (25%) Televisions (37%)

Market growth by appliance product category (CAGR), 2015 potential to 2020 potential

Fig. 3 Relative potential of market growth for super-efficient appliances (Global LEAP 2016)

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grid appropriateness. The objective of the Awardsis to fill a vital gap in market intelligence throughthe provision of laboratory-tested product data,thereby accelerat ing early stage—but st i l lnascent—product markets and near-to-market tech-nology. The inaugural Global LEAP Awards com-petition in 2013 included competitions for off-gridLED room lighting and off-grid TVs and has sinceexpanded to include fans and refrigerators.

Each Awards competition round (i.e., competi-tion year) consists of a research and planningphase before the launch, which is followed byproduct testing and evaluation, and ultimately anannouncement of winners and dissemination ofproduct information.

Pre-launch competition design and planning

Before launching an Awards round, a comprehensiveresearch and planning phase is undertaken to designeach competition in a way that optimizes its value tothe market, especially industry. For TVs, fans, and

refrigerators, this has included partnership cultivation,stakeholder consultation and research, test method de-velopment, creation of competition structure—such asevaluation criteria and rules—and communications. De-veloping relevant test methods, in particular, has re-quired significant time and effort. In most cases, off-grid specific test methods do not exist or have insuffi-cient criteria for evaluating off-grid fans, TVs, and re-frigerators, requiring input from product and testingexperts to develop and revise for use in the Awards.

Selection process and product evaluation

The launch of each competition officially opens a nom-ination window, during which off-grid appliance sup-pliers and distributors are solicited to nominate relevantproducts (TVs, fans, and refrigerators). Companiesnominating products are required to fill out a basicapplication with company details and product specifica-tions, as well as information about the product’s relevantoff-grid design. Nominated products are screened at thispoint for off-grid appropriateness based on factors such

Fig. 4 Map of appliance and geographic markets of interest of efficiency for access coalition members. Last updated June 2018

Energy Efficiency

as rated power requirements and costs. Selected prod-ucts are then sampled from companies’ warehouses andshipped to an accredited lab for testing. All products aretested for their energy performance, quality, and reliabil-ity and evaluated by a panel of off-gridmarket experts.19

Global LEAP identifies Winner and Finalist productsthrough a combination of this expert evaluation andenergy- and cost-based quantitative assessments, suchas lifetime cost of product.

Impact and applications

Since the inaugural competition, two more rounds of theGlobal LEAPAwards have been run, following signalsthat the off-grid appliance market emerged as a criticalpiece of the larger global off-grid clean energy market.In 2015 (the second round), the Awards expanded toinclude TV20 and fan21 competitions, and in 2017 (thethird round), TV,22 fan,23 and refrigerator24 competi-tions. The 2015 Awards received 53 product nomina-tions, of which 26 models from 11 companies wereidentified as quality, off-grid appropriate products andincluded in the published Global LEAP Buyer’sGuide.25 The 2017 Awards received 128 product nom-inations, of which 49 models from 20 companies wereidentified as quality, off-grid appropriate products andincluded in the published Global LEAP Buyer’sGuides26.27

In the aftermath of the inaugural 2013–2014Global LEAP Awards, it was recognized that se-vere cash-flow constraints, perceived risk (bothfinancial and technical), and a prevailing lack ofsophistication with respect to appliance businesslines on the part of off-grid solar distributors con-tinued to prevent large-scale procurement of off-grid appliances by leading SHS companies. Thiswas observed to be the case even among importantearly mover companies. Companies had expresseda desire to start selling appliances. The idea ofpairing the Global LEAP Awards, which vet appli-ances for quality and performance, with results-based financing (RBF) procurement incentives,which mitigate financial risk for both SHS compa-nies and appliance manufacturers, emerged in re-sponse to this recognition.

The Global LEAP appliance procurement incentives

In 2014, CLASP, the US Department of Energy(US DOE) and the IFC, with funding from EnDev,a multi-lateral energy access initiative, launchedthe inaugural Global LEAP Appliance ProcurementIncentives program (also known as Global LEAP+RBF). The program’s overarching goal is to cata-lyze the global market for high-quality, super-efficient off-grid appliances by demonstrating itsviability to essential market and value chain stake-holders. In doing so, the program attempts toaddress many of the barriers currently inhibitingthe growth of the off-grid appliance market listedin previous sections.

The program does this by leveraging theworld’s best-in-class off-grid appliances identifiedthrough the Global LEAP Awards competitions andoffering financial incentives (i.e., subsidies) to off-grid energy companies in key markets to procureand sell Global LEAP Award winning and finalistproducts at meaningful scale. These two core ac-tivities in turn drive the following activities andimpacts, all of which are essential to scaling thenascent off-grid appliance market:

& Generate critical market intelligence by collectingand disseminating data on product performance,commercial trends, consumer feedback, and marketcharacteristics, and building awareness of key off-

19 For further details on the test methods, as well as a discussion ofpreliminary results and observed trends, please see the paper titledBOff-Grid Appliance Data Trends: Results and Lessons Learned fromProduct Testing^ also available in this journal issue.20 2015 Global LEAPAwards-TVs: http://globalleap.org/2015-2016-tv21 2015 Global LEAPAwards-Fans: http://globalleap.org/2015-2016-fans22 2017Global LEAPAwards-TVs: http://globalleap.org/2017-buyers-guide-tvs23 2017 Global LEAP Awards-Fans: http://globalleap.org/2017-buyers-guide-fans24 2017 Global LEAP Awards-Refrigerators: http://globalleap.org/2017-buyers-guide-for-refrigerators25 2015 Global LEAP Buyer’s Guide (fans and TVs): https://static1.squarespace.com/static/56ba427f9f726695ab77ec09/t/5877ebf8e4f c b 5 7 1 d 5 a a a 3 7 d / 1 4 8 4 2 5 4 2 0 8 1 7 7 / 2 0 1 6+Global+LEAP+Awards+Buyer%27s+Guide+%28May+2016%29.pdf26 2017 Global LEAP Buyer’s Guide (fans and TVs): https://static1.squarespace.com/static/56ba427f9f726695ab77ec09/t/5995dee237c5813bc87af992/1502994152664/2017-Global-LEAP-Buyer%27s-Guide%2D%2DTVs-and-Fans-%28August-2017%29.pdf27 2017 Global LEAP Buyer’s Guide (refrigerators): https://static1.squarespace.com/static/56ba427f9f726695ab77ec09/t/5a969f4124a694da85ab9282/1519820612724/2017-Global-LEAP-Buyers-Guide-Refrigerators-January-2018.pdf

Energy Efficiency

grid national and regionalmarkets, enabling smarter,more targeted market action;

& Highlight the off-grid appliance market opportunityto appliance manufacturers and product developerswho have not yet explored this rapidly emergingmarket, thereby encouraging further market entry;

& Demonstrate the Bbankability^ of the off-grid appli-ance market to investors and commercial lenders;

& Support policymaker efforts to develop new policymodels that enable and encourage market growth,such as off-grid appliance standards and importtariff and tax reforms;

& Connect and facilitate relationships between marketstakeholders—including appliance manufacturers,off-grid energy companies, and financiers—to en-able smoother market functioning.

Winner and Finalist products of a given GlobalLEAP Awards round are eligible to participate inthe matching Global LEAP Appliance ProcurementIncentives program.28 The incentives are availableto appliance manufacturers and off-grid solar com-panies that partner with each other to distributecommercially viable quantities of Global LEAPAward Winner and Finalist products in targetgeographies.

The incentives are designed to reduce riskacross the off-grid appliance supply chain by (1)lowering the cost of best-in-class off-grid appli-ances for early mover off-grid solar companiesand (2) providing a ready customer base for appli-ance manufacturers that invest in the production ofhigh-quality off-grid appliances.

The second round of the procurement incentivewindow for eligible Global LEAP TVs and fansofficially opened on October 16, 2017, and thevolume of incentive claims submitted within thefirst 72 hours exceeded expectations. By the endof the first week, 27 unique incentive claims weresubmitted, which together accounted for 60,405TV products and 225,825 fan products. The aggre-gate value of these claims exceeded the availablepot of incentives. Due to this large response,CLASP closed the incentive window on October20, 2017—5 days after it opened. To date, theprocurement incentives program is supporting the

sale of over 230,000 highly efficient TVs, fans,and refrigerators across Kenya, Uganda, Tanzania,Rwanda, and Bangladesh.

The Global LEAP off-grid refrigerator competitionand test method overview

Off-grid refrigeration: opportunities and challenges

The 2016–2017 Global LEAP Awards Off-GridRefrigerator Competition29 was the first competi-tion to identify and promote the world’s best-in-class off-grid refrigerators. The competition wasfocused on off-grid refrigerators designed forhousehold or small retail applications and open tocommercially available and late-stage prototypeproducts.30

Designing a Global LEAP competition for refrigera-tors presented a unique challenge, as they are one of themost challenging off-grid appliances to design and de-velop to be both energy-efficient and cost-effective. Theoff-grid markets for technologies from previouscompetitions—LED lights, fans, and TVs—are relative-ly mature. These markets are reaching commoditizationas new players continue to enter the market with inno-vations in technology and/or cost. For example, theGlobal Off-Grid Lighting Association (GOGLA31) esti-mates that over 7 million solar lanterns and multi-lightsystems were sold in 2017 (GOGLA, 2017) and that thepay-as-you-go (PAYG) off-grid solar energy providerM-kopa32 has sold over 100,000 solar-powered TVs tocustomers in East Africa.33

The refrigeration competition also presented anopportunity to make improvements in a technologythat has clear socioeconomic impacts. Refrigerationprovides singular benefits spanning health and pro-ductivity and significantly reduces the domesticburden on women and children, who are usuallyresponsible for food gathering and preparation.Outside of home use, refrigeration is indispensablein hospitals and clinics—specifically for vaccine

28 Global LEAPOff-Grid Appliance Procurement Incentives program:http://globalleap.org/incentives/

29 Global LEAP Off-Grid Refrigerator Competition, 2016–2017:http://globalleap.org/refrigerators/30 More information can be found in Competition’s terms and condi-tions: http://globalleap.org/s/Global-LEAP-Awards-2016-17-Off-Grid-Refrigerator-Competition-Overview-20-Sep-16.pdf31 GOGLA: www.gogla.org32 M-Kopa Solar: http://www.m-kopa.com/33 TechMoran: https://techmoran.com/m-kopa-connects-100000-homes-to-paygo-solar-tv/

Energy Efficiency

storage—and unlocks productive potential in com-munities for uses spanning agriculture, small busi-ness and restaurants, beverage retailers, and more(GOGLA 2018; Jones et al. 2016).

The conventional alternative current (AC) compres-sor refrigerators available in emerging markets consumebetween 1 and 2.5 kWh per day, whereas the typical off-grid energy system does not produce sufficient energy topower these systems (Efficiency for Access 2018).Moreover, such refrigerators are often over-sized andover-priced for the typical off-grid consumer.34

However, as demand for refrigeration grows, both indomestic and in commercial markets, new refrigeratorsthat are designed explicitly for use with a stand-alone solarhome system are emerging. These refrigerators are gener-ally smaller and consume significantly less energy thanconventional products, some as low as 0.1 kWh per day.35

Figure 5 shows how a highly efficient andappropriately designed refrigerator can radicallycut the amount of energy—and the associated cap-ital cost—needed to power a suite of off-gridappliances. Such measures would make refrigera-tion accessible to a much larger portion of the off-and weak-grid population.

Introduction of innovation prizes and field testingto the Awards

Companies interested in tapping into the large unmetdemand for refrigeration in off-grid markets lack keytechnical product information and do not know whichcompanies are selling the best products. Refrigeratormanufacturers also lack the technical understanding ofhow products need to perform for off-grid use. Conven-tional test methodologies are inadequate for assessingquality and off-grid appropriateness in refrigerators. Thepower demanded from a suite of devices is of particularimportance in an off-grid power system because it de-termines the sizing of the PV panels and battery, ulti-mately impacting price.36

To address the gaps identified above, and with supportfrom the Department for International Development(DFID), Global LEAP developed a first-of-its-kind off-grid refrigerator test method in 2016. The Global LEAPOff-Grid Refrigerator Test Method was developed in con-sultation with market, product, and testing experts througha working group reviewing and commenting process.37

Leveraging the existing International ElectrotechnicalCommission (IEC) test methods for household refrigera-tors and World Health Organization (WHO) test protocolfor off-grid vaccine refrigerators,38 the test method wasdeveloped and modified in order to better evaluate energyconsumption and energy performance of a household re-frigerator in off-grid environment.

Refrigerator Technology Type and Definition

Products eligible for the 2016–2017 Global LEAPAwards Off-Grid Refrigerator Competition and the Inno-vation Prize are commercially available refrigerators orrefrigerator–freezer combination units—the two commontypes of refrigerators currently available in off-grid mar-kets. Therefore, the baseline testing efforts primarily fo-cused on these two types of refrigerator configurations:

& Refrigerators have one or more fresh food compart-ments for the storage and preservation of unfrozen foodand beverages,where the average storage temperature isat 4 °C (39.2 °F). Another common type of refrigeratorshas one ormore compartments that can either be used asa refrigerator or a freezer by adjusting the thermostatcontrol. In the context of the Global LEAP Awards,these types of products are tested as refrigerators.

& Refrigerator–freezer combination units have a com-bination of at least one fresh food and at least onefreezer compartment, where the storage temperatureis not warmer than − 18 °C.

34 For a more in-depth overview of the off-grid refrigerator market andrelated efficiency trends, please see the paper titled BOff-Grid Appli-ance Data Trends: Results and Lessons Learned from Product Testing^also available in this journal issue.35 This represents the most efficient product nominated for the 2016–2017 Global LEAPAwards for Off-Grid Refrigerator Competition.36 Narayan , N. , Qin , Z . , e t a l . h t tps : / / l i nk . sp r inger.com/content/pdf/10.1007%2Fs12053-018-9725-6.pdf

37 CLASP procured a total of 36 products online, direct from manu-facturers, and through field agents in off-grid areas. Among the 36 testsamples, 24 were refrigerator–freezer combination units (67%), and 12were refrigerators only (33%). These products underwent testing inaccredited laboratories according to the Global LEAP Off-Grid Refrig-erator Test Method to evaluate their energy performance, servicedelivery, durability, and off-grid appropriateness. You can find theGlobal LEAP Off-Grid Refrigerator Test Methods here: https://bit.ly/2LwTy0u and learn more about the results in the paper titled BOff-Grid Appliance Data Trends: Results and Lessons Learned fromProduct Testing^ also available in this journal issue.38 The following international refrigerator test procedures were refer-enced in the preparation of the Global LEAP test method: IEC62552:2015, WHO/PQS/E003/RF05-VP.4, and IEC 60068-2-78:2012

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Baseline testing results—energy efficiency and retailprice

Since off-grid consumers are price-sensitive and energy-constrained, striking a balance between efficiency andprice is often a critical business consideration for marketactors in the off-grid sector (Aste et al. 2017). This

section provides some initial insights on the dynamicsbetween price and efficiency for refrigerators.

Figure 6 provides an overview of efficiency valuesand retail price of baseline products. To enable a com-parison of refrigerators and refrigerator–freezers acrossall sizes, an efficiency metric was used for the analysis:daily energy consumed per unit size of a refrigerator,

15”

1 TV

1 Pedestal Fan

1 Phone Charger

1 Radio

4 LED Lights 1 Refrigerator

80 WpSolar Panel

700 WpSolar Panel

8.75 x

35 AhLead Acid Battery

8.57 x

300 AhLead Acid Battery

Energy System RequirementsEnergy system needed to support a conventional on-grid refrigerator

Energy system needed to support an

KEY

Fig. 5 Efficient and appropriately designed refrigerators dramat-ically reduce energy system requirements. The Bappropriatelydesigned, super-efficient refrigerator^ in this scenario consumes0.1 kWh per day and has an 80 L capacity. These figures are basedon rated performance data from the most efficient product nomi-nated for the 2016–2017 Global LEAP Awards Off-Grid

Refrigerator Competition. The Bconventional on-grid refrigerator^consumes 1.75 kWh per day and has a capacity of 691 L. This datawas obtained from the Consortium for Energy Efficiency’s data-base and reflects typical developed world preferences and marketofferings

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Product Source | OEM, Field (FLD), Off-Grid Product Designer (OPD)

Efficiency Metric vs. Retail Price

Efficiency at 32°C (kWh/liter) Retail Price [USD]

Most Efficient

Least Expensive

MostExpensive

LeastEfficient

Fig. 6 Refrigerator energy efficiency vs. retail price

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defined as kilowatt hour per liter. The blue bars repre-sent the energy efficiency values, and the orange linerepresents retail prices (in USD). The orange trend lineshows the correlation between these two metrics.

The analysis indicated that (1) the price of productsvaries considerably, (2) some of the products currentlyavailable in the market are already highly energy effi-cient, and (3) efficiency is negatively correlated to retailprice—highly energy efficient products tend to be moreexpensive compared to lower energy efficient products.

We conducted additional analyses to compare thetrends of efficiency and price based on the followingvariables: refrigerator type, size, source, and power sup-ply type, summarized in Fig. 7. Again, the orange line isthe retail price in USD. The analysis indicates that (1)efficiency varies most among small refrigerator/refrigerator–freezer combinations, (2) these refrigeratortypes also tend to be the least efficient products, and (3)price varies significantly among all small refrigeratortypes.

Introduction of innovation prizes and field testingto the Awards

The refrigeration competition introduced a unique fea-ture to the Global LEAP Awards, since three USD$200,000 innovation cash prizes were made availableas part of the overall prize purse. All nominated productsthat satisfactorily completed the competition’s laborato-ry testing process based on the Global LEAP Off-GridRefrigerator Test Method discussed above were eligiblefor innovation prizes for products that demonstratemarket-leading innovation in (1) overall value, (2) en-ergy efficiency, and (3) appropriate design and userexperience.

The prizes were sponsored by the U.S. Global De-velopment Lab39 and DFID’s Ideas to Impact program40

as part of their commitment to the Scaling Off-GridEnergy: A Grand Challenge for Development.41

Prizes (1) and (2) were evaluated based on laboratorytest results and additional information provided by nom-inees. Following the evaluation of these results by anexpert panel of judges, the winners of the first twoinnovation prizes were announced at the end of January

2018 in Hong Kong at the Global Off-Grid Solar Forumand Expo.42

The third innovation prize was based on field testingof eligible products to understand product performancein real-life conditions, as well as assess the impact ofthese products to off-grid low-income users. Prior tofield-testing, Energy 4 Impact (E4I),43 CLASP’s imple-mentation partner in the field testing component of thecompetition, conducted a baseline study of 172 micro-enterprises using on-grid AC refrigerators in Uganda tobetter understand the productive use case for off-gridrefrigerators (Grid Powered Refrigeration forProductive Use 2017).

The baseline study found a clear business case forrefrigerators, with 50% of respondents in the studyshowing increased revenues through diversified busi-ness models and/or expanded product offerings. Despitethese benefits, entrepreneurs faced challenges of quality,grid unreliability, efficiency, and service delivery. Theuse of inefficient refrigerators was found to be closelylinked with stifling the growth of a business, or resultingin reduced profits.

For instance, one entrepreneur identified an opportu-nity to sell ice cream but was unable to do so because theincrease in their electricity cost from running an ineffi-cient fridge at the required temperature was prohibitive.Similarly, businesses have learned to manage the signif-icant energy consumption of their refrigerators—andavoid high electricity bills—by running them only forintermittent periods of time instead of continuously.

Consequently, autonomy—the ability of a refrigera-tor to maintain the desired temperature when discon-nected from the power supply—is a highly valued fea-ture in off-grid refrigerators. Entrepreneurs are willing topay more for this feature and are more tolerant of refrig-erators with both high autonomy and higher powerconsumption, rather than low autonomy even withslightly lower power consumption.

In lab tests, autonomy testing measures the numberof hours it takes for a product’s compartment tempera-ture to rise from 4 to 12 °C with no external powersupply. The autonomy test simulates how a productwould operate in the event of a battery failure or in theabsence of available power supply. Figure 8 shows the

39 Global Development Lab: www.usaid.gov/GlobalDevLab40 Ideas to Impact: www.ideastoimpact.net/41 Scaling Off-Grid: www.scalingoffgrid.org/

42 Official announcement of the winners of the two Innovation Prizes:https://www.energy4impact.org/news/global-leap%E2%80%99s-grid-refrigerator-competition-and-innovation-prize-winners-announced43 Energy 4 Impact: https://www.energy4impact.org/

Energy Efficiency

autonomy hours of all baseline tested products, whichranged from 0.6 to 2.6 h. The average value of autono-my was approximately 1 h.

The durability and serviceability of refrigerators werealso found to be characteristics important to the busi-nesses surveyed. More than a third of entrepreneurs inthe study declared that they had bought their refrigera-tors used—and entrepreneurs reported these used refrig-erators malfunction frequently and are expensive torepair or replace. This is particularly problematic be-cause the refrigerators, even when not functioning opti-mally, are often critical to keeping their businesses run-ning, and any disruption, even a short downtime formaintenance, can significantly impact their livelihoods.

Field testing methodology

Overview

Following the successful completion of the laboratorytesting process, all eligible refrigerators were shippedfrom the testing laboratory in the Netherlands to Ugandafor field testing. The aim of the field testing was todemonstrate how these products perform in Breal-life^conditions, supplemented by information from endusers regarding their experience using these products.

Market dynamics indicate that small retail buyers arethe most likely early adopters of refrigeration technology,given both the high cost of the products and their potential

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to generate new revenue sources. In line with the baselinestudymentioned above, retail shopswere hence selected asthe best possible sites for evaluation of field performanceof the refrigerators. Uganda was chosen as the location forthe field testing for two primary reasons: (1) presence of acountry office and team from E4I to manage the processand (2) the widespread use of off-grid solar power inUganda, which wouldmake it easy to identify participants.

The E4I team completed a market survey acrossUganda to select field test sites based on the followingcharacteristics:

& Business profile: Small retail shops, to the extentpossible, of similar size with similar clientele andproduct offerings

& Climate and location: Retail shops in similar cli-mactic zones to mitigate variability in humidity andambient temperature and, where possible, in prox-imity of each other to facilitate data collection

& Familiarity with solar technology: Entrepreneurstesting the refrigerators have previous experienceusing solar home systems either at the test site orin their homes (e.g., use of a system for lighting andmobile phone charging).

& First time users: Entrepreneurs testing the refrigera-tors do not currently own or use a refrigerator. Thisenables assessment of a product’s commercial ben-efits (e.g., new revenue generation) and whetherproducts are perceived as affordable and viable byrepresentatives of a target market segment.

Data gathering

Technical data Each refrigerator being tested was con-nected to a stand-alone solar energy system independentof any existing solar energy systems in operation at thetest site. The program team contracted a qualified third-party subcontractor to size and design the systems basedon the performance characteristics and energy supplyrequirements of the products to be tested (i.e., powerrating, AC/DC power requirements) as identified previ-ously in the test lab reports. All installations were con-ducted by a qualified solar technician.

Remote monitors were installed in the refrigerators tocollect real-time energy consumption data spanning: (1)instantaneous power consumption, (2) accumulated en-ergy consumption, and (3) daily power available to theproduct from the solar home system/battery.

The original goal of the field testing process was tocollect detailed product performance data in addition toenergy consumption data. Unfortunately, due to a range oftechnical issues with the remote meters originally sourcedfor the testing process, the following data was not collectedfor the entire duration of the field test and hence omittedfrom the evaluation: (1) internal compartment temperature,(2) ambient temperature, and (3) relative humidity.

Findings based on user experience The quantitativedata described above was supplemented by qualitativedata collected through entrepreneur interviews adminis-tered by a team of trained enumerators. The aim of thesesurveys was to collect more nuanced feedback on per-ceived technical performance, ease of use, perceivedvalue, and overall benefits and challenges experiencedby first-time users of the technology.

The physical integrity and durability of the productwere also assessed by recording the physical conditionof the fridge before the trial and at the time of each bi-weekly visit by an enumerator. This information wasgathered through a visual assessment of each productand recorded on a standard form, with photos assupporting evidence.

Field testing results

Field testing of the Global LEAP Awards Winning andFinalist refrigerators officially commenced in mid-June2018 in rural Uganda and ran until the end of August2018. Each product’s technical performance data, alongwith qualitative feedback from the testing entrepreneurswith regard to the utility, perceived value, and usabilityof the products, along with any relevant business re-cords, were collectively analyzed. The results weresummarized and presented to a panel of expert judgesfor evaluation. Their evaluation was used in determiningthe winner of the third innovation prize, which wasannounced in November 2018.

The following section focuses on two major findingsthat highlight why additional field testing is required tounderstand usage patterns and implications on powerconsumption and overall system design, as well as theimportance of a feedbackmechanism for manufacturers.A publication with an in-depth analysis of the results isforthcoming.44 The analysis will include a thorough

44 In-depth report will be available in early January 2019 on theEfficiency for Access coalition website

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evaluation of the products lab tested performance vs.field tested performance augmented with qualitativefeedback from test users.

Energy consumption—laboratory vs. field performance

The power consumption of a given refrigerator dependson the refrigerator settings, amount of refrigerant used,speed regulations of the compressor, as well as therelative humidity (RH) and ambient temperature of thelocation. In lab tests, these are standardized or controlledfor to enable direct comparison of refrigerator perfor-mance. One of the key tests performed in the lab is theSteady-State Operation, which measures a product’senergy consumption (in kWh per day) at specified am-bient temperatures and humidity levels.

Figure 9 compares the product’s daily energy con-sumption as measured under high ambient conditions(+ 32 °C/RH 75%) in the lab compared with the prod-uct’s recorded average daily energy consumption ascollected by remote monitors in the field. While tem-perature and humidity readings are missing from thefield test results, instantaneous baseline temperatureand humidity readings collected at the start of the fieldtesting exercise indicate that these products were oper-ating at an average baseline temperature of 27 °C andhumidity of 69%.

The graph indicates that most products included inthe study consume significantly higher energy whenoperating in the field. One reason for this is that therefrigerators deployed in this study are primarily beingused to cool beverages. Entrepreneurs will try to maxi-mize the utility of their refrigerators by filling them tocapacity with drinks. Throughout the day, they will takeout cold drinks and re-fill the fridge with much warmerdrinks to replace those being sold. This cycle of constantreplacement greatly affects the power consumption ofthe refrigerator and the amount of time needed to cooldown drinks (Harrington et al. 2018).

Figure 10 further assesses at the variance in energyconsumption by refrigerator type and size. The graphshows that medium and large refrigerators in particularrequire much larger energy systems to operate thananticipated. This variance in energy consumption be-tween lab testing and field observations has significantimplications for energy system sizing. If 24 h operationis needed, these units would need to be installed withmuch larger PV and battery systems, which in turnmeans a greater total cost of product.

In addition, the majority of these businesses are runout of small shops with limited space to accommodate alarge asset such as a refrigerator. While entrepreneurscan be creative in making space to accommodate a newappliance, less efficient systems that require large ormultiple batteries to store energy are even more difficult

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to accommodate. This further underlines the need forrevisions to lab testing methods to have a more Breal-world^ use representation.

Ease of installation, use, and serviceability

Unlike AC refrigerators, which for the most part can beinstalled without the need for any additional hardware ora specialized technician, solar DC refrigerators still re-quire technical expertise for installation that goes be-yond appropriate system sizing of the SHS required topower the refrigerator. Related to low levels of comfortwith appliance technology as described above, entrepre-neurs will therefore depend on a local, often uncertified,technician to assist with the installation process.

Refrigerators that are designed to be as plug-and-playas possible, with clearly labeled connectors and easy-to-follow instructions, reduce the complexity associatedwith installation, and require less time for the setup.This reduces the total cost of installation as well asavoiding technical issues. Removing the guesswork in-volved in the installation process also greatly reducesthe likelihood of damage during installation. Manufac-turers should not underestimate the importance of hav-ing protectivemechanisms included in their models, andthere should be an open line of communication betweenthe manufacturers, the packaging and shipping teams,and the installation team to ensure everything goessmoothly with the supply chain process from start tofinish.

For example, some of the compressors used in thetested refrigerators required discharging of refrigerantgases to comply with shipping requirements. However,the packaging company failed to notify the program

team at CLASP that they had discharged these refriger-ators of refrigerant. Consequently, the technician doingthe installation was unaware that the refrigerators need-ed to be refilled with refrigerant before operation. As aresult, once connected, these refrigerators were found tobe consuming much higher power than expected and notcooling the compartments as well as they should be. Inthe absence of the program team at CLASP to coordi-nate communication between the manufacturer and thetechnician to identify and resolve the issue, the entre-preneurs would have abandoned these refrigerators asmalfunctioning.

The entrepreneurs selected for this experiment aregenerally much less familiar with appliances—and solartechnology more broadly—than a typical on-grid refrig-erator owner. Their English literacy is generally low,which means user manuals need to be designed accord-ingly. Making manuals more visually descriptive andincluding a list of basic Bdos and don’ts^ could helpavoid some seemingly obvious mistakes that arise dueto inexperienced user error.

For example, for a refrigerator–freezer combina-tion unit, each compartment needs to be clearlylabeled to indicate which is which, and the userneeds to be warned not to probe the fridge orpuncture components with a sharp object. Onerefrigerator sample has been damaged beyond re-pair after an entrepreneur damaged the compressorwhen attempting to remove ice with a knife. Usersshould also be instructed not to leave the refriger-ator door open or put hot items in the refrigeratorcompartments. Such basic instructions and tutorialswould help avoid most issues that arise with ap-pliance misuse.

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Fig. 10 Variance in daily energy consumption by refrigerator type—lab vs. field

Energy Efficiency

Conclusions and lessons learned

This paper highlights the need for more data and fieldtesting to better understand how refrigerators can bedesigned for an off-grid customer and to maximizeenergy performance.

The work that has been done through Global LEAPand the Efficiency for Access Coalition to improve theappropriateness of test protocols and test data availableis the most extensive effort to date to understand theenergy performance and service delivery of commer-cially available off-grid refrigerators at an early stage ofthe market’s development.

However, while lab tests (such as those conducted viathe Global LEAPAwards) enable companies and marketstakeholders to better understand product performance,the tests themselves are not sufficient in determin-ing the real-world performance of the system. Ini-tial observations of the variance in performancebetween lab and field testing point to the needfor more field testing to understand user behaviorand preference and how these affect overall per-formance of the refrigerators.

There is room for innovation among manufacturersto improve on the features that off-grid consumers aremost willing to pay for. For example, in the case ofautonomy, the average product on the market has anautonomy value of 1 h—manufactures optimizing forthis feature would be able to offer consumers moreattractive products and would thus increase their com-petitiveness in the market (Efficiency for Access 2018).

Beyond technical performance, manufactures need abetter understanding of the entire eco-system needed tomake their products work. Efficiencies that can begained to reduce the PV and battery storage require-ments to power the system, resulting in an overall lowercost of system, are needed to make these products viablefor price sensitive end-users.

Much more market intelligence is needed to collectthis information with clear feedback loops to productdesigners and manufacturers. The Efficiency for AccessCoalition recently hosted an Global Market Develop-ment Roundtable for Off-grid Refrigeration where over40 companies and market stakeholders came together todiscuss which interventions investors, donors, andothers should focus on to improve the broader marketecosystem (Efficiency for Access 2018a). New researchis underway to segment the market for off-grid refriger-ators and assess the commercial viability for each

segment. Following this, additional research will beundertaken on the segments to better understand theoff-grid consumer and measure socioeconomic impacts.Improved access to market intelligence and further tech-nological advances will bring more affordable refriger-ators to nascent markets.

Funding Lawrence Berkley National Laboratory (grant number7348019) and the UK’s Department for International Develop-ment’s Low-Energy Inclusive Appliances Program (grant number300111-103).

Compliance with ethical standards

Conflict of interest The authors declare that they have no con-flict of interest.

Open Access This article is distributed under the terms of theCreative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestrict-ed use, distribution, and reproduction in any medium, providedyou give appropriate credit to the original author(s) and the source,provide a link to the Creative Commons license, and indicate ifchanges were made.

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Energy Efficiency