A product of the USAID-NREL partnership

Contract No. AID-AFR-T-15-004

SURVEY USE IN MICRO-GRID LOAD 

PREDICTION, PROJECT 

DEVELOPMENT, AND OPERATIONS 

Review and Best Practices

Nathan Williams,1 Samuel Booth,2 and Ian Baring-Gould2

1 Carnegie Mellon University 

2 National Renewable Energy Laboratory

Technical Report 

NREL/TP-7A40-72339

May 2019
NOTICE

This work was authored in part by the National Renewable Energy Laboratory, operated by Alliance for 

Sustainable Energy, LLC, for the U.S. Department of Energy (DOE) under Contract No. DE-AC36-

08GO28308. Funding provided by the United States Agency for International Development (USAID) under 

Contract No. AID-AFR-T-15-004. The views expressed in the article do not necessarily represent the views 

of the DOE or the U.S. Government or any agency thereof, including the United States Agency for 

International Development.

This report is available at no cost from the National Renewable 

Energy Laboratory (NREL) at www.nrel.gov/publications. 

U.S. Department of Energy (DOE) reports produced after 1991 

and a growing number of pre-1991 documents are available 

free via www.OSTI.gov. 

Cover photo by Samuel Booth, NREL.

NREL prints on paper that contains recycled content. 
iii

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Acknowledgments

The National Renewable Energy Laboratory and Carnegie Mellon University thank Katrina Pielli and the 

Power Africa Beyond the Grid team for their support in the development of this report. The authors would 

also like to specifically thank Isaiah Lyons-Galante of PowerGen Renewable Energy for his partnership 

on the survey and demand analysis. Thanks also go to Robi Robichaud and Tim Reber for their review 

and input and to Britton Marchese for editing support. Finally, thanks to the other members of the microgrid development community who offered data, feedback, and time in support of this report, including:

• James Locken, PowerGen Renewable Energy

• Joanis Holzigel and Eva Lee, Rafiki Power

• Gordon Odhiambo and Brian Sikuku, Renewvia

• Ayodeji Abegbenro and Ola Oresanya, Rubitec Solar

• Bruno Lopes, RVE.Sol

• Brian Somers, Standard Microgrid

• Richard Mori, MeshPower

• Gianluca Cescon and Tommaso Girotto, Devergy.
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List of Acronyms

GIS geographic information system

HH household

LASSO Least Absolute Shrinkage and Selection Operator

M&E monitoring and evaluation

NREL National Renewable Energy Laboratory

SHS solar home system

SMS Short Message Service

TSH Tanzanian shilling

USD United States dollar
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Executive Summary

Micro-grids are proliferating in East Africa as alternatives to grid extension in communities far from 

existing grid infrastructure. Although many studies have found micro-grids to be cost-effective choices 

compared with the grid in remote areas (Moksnes et al. 2017; Moner-Girona et al. 2017; Nerini et al. 

2016; Szabó 2011), micro-grid developers face unique challenges. The Quality Assurance Framework for 

Mini-Grids (Baring-Gould et al. 2016) was developed to address many of those challenges, and this report 

builds on the Quality Assurance Framework.

Because micro-grids must meet local electrical loads with local generation, accurate community-level 

electrical load forecasts are critical to proper system design and financial modeling. Further, because 

these systems are largely operated by private, for-profit companies that generally do not benefit from the 

same subsidies as the main electricity grid, it is crucial to select micro-grid sites that will consume 

sufficient electricity to make the micro-grids financially sustainable. To learn more about prospective 

communities and customers, micro-grid developers often deploy surveys before selecting sites and 

building new micro-grids. Although it is known that micro-grid developers use survey tools, these 

activities are often developed and implemented internally. The current state of practice regarding the use 

of surveys to estimate market opportunities and electrical loads for remote communities is not well 

understood. 

This study was undertaken to identify current practices within the sector involving the use of surveys and 

their ability to accurately predict customer demand once connected to a micro-grid. Further, best practices 

are identified for survey use during micro-grid development and operation. This includes:

• Survey objectives

• Type of information collected

• Data collection and storage techniques

• Analysis methods.

To better understand current practices, eight micro-grid developers operating in sub-Saharan Africa were 

interviewed about their use of surveys. The developers were chosen to represent a diversity of 

geographies, technical approaches, and business models. Although the depth and approach to conducting 

surveys differed among developers, all of them conducted surveys as a normal part of doing business. 

This assessment also determined that, although there are no defined standard practices around survey 

techniques across the sector, a similar category of studies with like objectives is typically undertaken. 

These include surveys for:

• Market research

• Site selection

• Customer applications

• Customer satisfaction

• Socioeconomic monitoring and evaluation. 

Using data from more than 1,000 micro-grid customers in Tanzania, several statistical methods are 

examined to determine which survey questions will better predict actual customer electrical loads after 

initial connection. This study identifies the following questions that seem to best indicate potential future 

energy use:
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• Customer class (Home, Business, Home/Business, Public Premises)

• Nature of business

• Employment status

• Current source of energy and uses

• Current mode of transport 

• Appliances owned before micro-grid connection

• Building construction materials

• Mobile phone airtime spending

The data generated by answers to these questions were then analyzed using three methods, including 

correlation to actual energy usage, a Least Absolute Shrinkage and Selection Operator regression, and a 

random forest model. The correlation to actual energy usage is illustrated in Figure ES-1. A positive 

coefficient means that the variable is positively correlated with electricity demand, whereas a negative 

coefficient shows negative correlation. Energy sources, transport modes, pre-electrification appliance 

ownership, building type, connection class, and business type feature strongly.

Figure ES-1. Correlation coefficients between survey variables and daily electricity consumption 

in first 90 days since connection to the micro-grid.1

Note: Household (HH) income is for households only (1 United States dollar [USD] ≈ 2,250 Tanzanian shilling [TSH]).

It should be noted however, that there appears to be a difference in opinion and approach among 

developers with regards to predicting electrical load. On one end of the spectrum, developers allocate 

significant resources to collecting data on customers and applying sophisticated quantitative models to 

forecast electrical load in order to optimize system design and project revenue. On the other end of the 

 1 The names shown in Figure-ES-1 correspond to the survey response options given to customers. See Section 3 and 

the report Appendix for more details and explanation of the chart and the names. For example, building type refers 

to the construction material of residential homes and wake time: other refers to customers that wake up at a time 

other those specified in the survey. 
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spectrum, some developers are skeptical that forecasting load is feasible and rather deploy modular 

systems that can exert more control over consumption. We are unable to draw conclusions on the relative 

performance of these approaches due to limited data and a small sample. 

The objectives of using surveys to predict demand are twofold. Developers seek to identify the most 

financially viable micro-grid sites which is in large part a function of electricity demand. This information

is also required to design systems that meet customer demand at minimum cost. The timing of these 

surveys introduces a trade-off. Surveys provide valuable information on the basis of which developers 

select micro-grid sites but are expensive to run. If surveys are conducted before site selection decisions, 

additional expense will be incurred for unselected sites. However, if surveys are completed only after site 

selection, good sites may be overlooked. A middle ground is to conduct surveys on a sample of potential 

customers during initial site visits prior to site selection.

Drawing on experience from a range of eight sub-Saharan African micro-grid developers, the second 

main outcome of this work is a set of best practices for the use of surveys at different stages of micro-grid 

development and operations. These best practices include:

• The level of data collection needed to meet specific business or national energy access goals should 

be defined early and well understood.

• Develop surveys using standard or accepted survey techniques.

• Survey questions should be pretested to ensure that they are interpreted accurately and consistently by 

respondents.

• Surveys to estimate expected energy consumption should use questions that have been identified as 

important predictors of consumption, such as those identified in this study.

• Because estimates of income can be difficult to obtain and subject to bias, proxies of wealth may be 

better methods to determine eventual energy usage than income estimates.

• Surveys should be conducted using mobile device-based assessment tools using clear survey 

instruments.

• Well-trained and experienced survey enumerators who are fluent in the local language, have 

experience in energy issues, and understand potential cultural sensitivities should be used.

• Incorporating a set of standard questions in all surveys to allow comparison across projects and over 

time will be valuable.

Finally, we propose a set of standard survey tools that can act as a core set of questions that micro-grid

developers can use in creating their own surveys.
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Table of Contents

1 Introduction ..........................................................................................................................................................1

1.1 Objectives of Study.......................................................................................................................... 1

1.2 Role of Surveys in Micro-Grid Development.................................................................................. 2

1.3 Interview Method............................................................................................................................. 2

2 Findings.................................................................................................................................................................5

2.1 Market Research Surveys ................................................................................................................ 6

2.2 Site Identification Surveys............................................................................................................... 6

2.2.1 Data Collected................................................................................................................... 6

2.2.2 Collection Methods........................................................................................................... 8

2.2.3 Logistic and Financial Considerations.............................................................................. 9

2.2.4 Analysis Techniques....................................................................................................... 10

2.2.5 Lessons Learned.............................................................................................................. 10

2.3 Customer Application Surveys...................................................................................................... 11

2.3.1 Data Collected................................................................................................................. 11

2.3.2 Collection Methods......................................................................................................... 11

2.3.3 Logistic and Financial Considerations............................................................................ 12

2.3.4 Analysis Techniques....................................................................................................... 13

2.3.5 Lessons Learned.............................................................................................................. 13

2.4 Customer Satisfaction Surveys...................................................................................................... 14

2.4.1 Data Collected................................................................................................................. 14

2.4.2 Collection and Storage Methods..................................................................................... 15

2.4.3 Logistic and Financial Considerations............................................................................ 15

2.4.4 Lessons Learned.............................................................................................................. 15

2.5 Project Specific Socioeconomic Monitoring and Evaluation Surveys .......................................... 15

2.5.1 Surveys and Productive Use ........................................................................................... 16

3 Surveys for Electrical Load Prediction.............................................................................................................17

3.1 Customer Surveys in Tanzania ...................................................................................................... 17

4 Best Practices......................................................................................................................................................22

4.1 Survey Design................................................................................................................................ 22

4.1.1 Writing Questions........................................................................................................... 22

4.1.2 Sources of Bias................................................................................................................ 22

4.1.3 Survey Length................................................................................................................. 24

4.2 Survey Implementation.................................................................................................................. 24

4.3 Survey Analysis............................................................................................................................. 25

5 Conclusions.........................................................................................................................................................26

References ..................................................................................................................................................................28

Appendix ....................................................................................................................................................................29
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List of Figures

Figure ES-1. Correlation coefficients between survey variables and daily electricity consumption in first

90 days since connection to micro-grid....................................................................................................................... vi

Figure 1. Correlation coefficients between survey variables and daily electricity consumption in first 90 

days since connection to micro-grid............................................................................................................................18

Figure 2. Random forest variable importance for electricity demand prediction..............................................20

List of Tables

Table 1. Summary of Interview Questions..................................................................................................................3

Table 2. Categories of Frequently Collected Data during Site Selection Surveys..............................................7

Table 3. Collection Methods...........................................................................................................................................8

Table 4. Variables Selected in LASSO Regression Model Including the Sign of Model Coefficients .......19

Table 5. Proposed Survey Questions for Electrical Load Estimation..................................................................21

Table A-1. Summary of Customer Application Survey Questions and Response Options............................29
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1 Introduction

Micro-grids are proliferating in Africa as an alternative to waiting for grid extension in communities far 

from existing grid infrastructure. Many studies have found micro-grids to be cost-effective choices 

compared with the grid in remote areas (Moksnes et al. 2017; Moner-Girona et al. 2017; Nerini et al. 

2016; Szabó 2011).

Carnegie Mellon University and the National Renewable Energy Laboratory (NREL) authored this report 

with support from Power Africa and USAID. It is a resource for developers, policymakers, regulators, and 

other stakeholders to better understand how to use surveys to support electricity load prediction, project 

development, and operations for micro-grids. Improved customer demand/usage production, site 

selection, and micro-grid development and operation will help developers scale micro-grids faster.

NREL and the U.S. Department of Energy have developed a Quality Assurance Framework for MiniGrids (Baring-Gould et al. 2016). This framework, developed with the intent of fostering mini-grid 

growth and rural electrification, has the dual goals of:

1. Defining a range of service levels that ensure safe, quality, and affordable delivery of electricity.

2. Providing an accountability framework that can be used to determine whether an agreed-upon 

service level has been delivered. 

This report focuses on smaller micro-grids with a capacity less than 1,000 kilowatts located in subSaharan Africa and is a companion document to the Quality Assurance Framework.2

1.1 Objectives of Study

The objectives of this study are threefold: 

1. Identify common pre-project survey types, objectives, characteristics, tactics, and practices 

employed by micro-grid developers with direct experience in sub-Saharan Africa.

2. Identify survey questions which are most useful in accurately predicting customer demand once 

connected to a micro-grid.

3. Use input from the first two sections to develop best practices advice for micro-grid developers.

Combined, this information can serve as a guide for a range of users, including micro-grid developers, 

government officials, regulators, policymakers, and other stakeholders. 

Many micro-grid developers, because of size, experience, and financial resources, rely on some internal 

or informal survey tools and practices to learn more about the potential markets where they are 

considering developing new micro-grid projects. The first objective of this study is to identify current 

practices within the sector involving the use of surveys. This includes survey objectives, the type of 

information collected, data collection and storage techniques, and analysis methods. 

The second objective is to identify survey questions which are most useful in accurately predicting 

customer demand once connected to the micro-grid using two statistical approaches that attempt to relate 

 2

The terms “mini-grid” and “micro-grid” do not have clear or consistent internationally recognized definitions and 

are used somewhat interchangeably by many industry stakeholders and practitioners. In this report, the single term 

“micro-grid” is used for simplicity with no attempt to distinguish it from the term “mini-grid,” which could also 

apply in most instances.
2

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customer characteristics with electricity demand/consumption. This work is based on actual customer 

electricity consumption and survey data for more than 1,000 micro-grid customers in East Africa.

Third, drawing on experience from a range of micro-grid developers, a set of best practices will be 

identified for the use of surveys at different stages of micro-grid development and operations. 

Additionally, several standard survey tools will be proposed that can act as a core framework with 

appropriate questions that micro-grid developers can use in creating their own surveys. Developing a 

standard set of data to be collected across the sector will help facilitate more equitable monitoring and 

evaluation of micro-grids by regulators, financiers and investors, and other industry stakeholders. Such 

standardized data collection will also allow for expanded learning about regional and national energy use 

assessments and predictions. The resulting data sets may help open the door to standardized project 

assessment methods that could streamline regulation and investment across the sector, resulting in lower 

transaction costs, more investment, and increased electrification.

1.2 Role of Surveys in Micro-Grid Development

While it is known that micro-grid developers use survey tools, these activities are often developed and 

implemented internally. Current practices on the use of surveys are not well understood or documented. 

Micro-grid developers face unique challenges such as accurately forecasting future electricity demand in 

their micro-grids. 

Electrical load forecasts are key in planning the central power system, although the total electrical load in 

any particular community is less critical, because both temporal and spatial variability are smoothed 

through aggregation and averaging energy usage. Because micro-grids must meet local electrical loads 

with local generation, accurate community-level electrical load forecasts are critical to effective system 

design and financial modeling. Further, because these systems are largely operated by private, for-profit 

companies that generally do not benefit from the same subsidies as the main electricity grid, it is crucial 

to select micro-grid sites that will demand sufficient power to make the micro-grids financially 

sustainable. To learn more about prospective communities and customers, micro-grid developers often 

deploy surveys prior to selecting and building new micro-grids.

Furthermore, micro-grid operators are often very customer-centric enterprises and engage with their 

customers during operations to gauge customer satisfaction, respond to evolving customer needs, identify 

opportunities to offer new services, and support growth in demand for electricity. There is also interest 

among the larger set of stakeholders in monitoring and evaluating the socioeconomic impacts of microgrids on the communities they serve. Therefore, operators also conduct surveys to improve customer 

service, estimate the need for expanded supply, and measure the impacts of their activities.

1.3 Interview Method

This study relies on data collected during semi-structured interviews with micro-grid companies that 

actively develop and operate micro-grids in Africa. Participants were provided a list of questions before 

the interview that were used to guide the discussions. To allow a free-flowing conversation and identify 

pertinent information that the questions may not address, the questions were not posed sequentially. One 

interview was carried out in person, with the balance of the oral exchange conducted telephonically. On 

average, the interviews lasted approximately 1 hour. One developer provided a written response to the 

survey questions before the interview.

The framework of the questions that formed the basis of the interviews was divided into four categories: 

(1) questions about the surveys themselves, (2) questions about the analysis carried out using the survey 

data, (3) a set of questions specifically about the micro-grid site and customer selection, and (4) questions 

about survey use for monitoring and evaluation. A summary of the interview questions is in Table 1.
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Eight micro-grid developers were interviewed. Efforts were made to capture a breadth of experience, 

geography, and approach from the population of developers in Africa. Geographically, the developers 

interviewed operate in East, West, and Southern Africa. In terms of experience, developers range from 

those operating a single site to those with more than 20. Most of the micro-grids charge customers per 

unit of energy consumed; however, some of the operators charge based on duration of energy or 

appliances used. Most of the developers have built and operate alternating current networks, though two 

of the developers have built primarily direct current grids.

Table 1. Summary of Interview Questions

Questions on Surveys

Do you use surveys as part of your micro-grid development and/or operations processes?

What are the objectives of your surveys?

Whom do your surveys target? Do you have different surveys for different customer segments? If so, how do you 

segment your customers?

How do you collect the survey data (e.g., in person on paper, in person via tablet/phone)?

Is there a particular software you use in conducting surveys (e.g., smartphone apps, etc.)?

What data do you collect? Can you share your survey?

Are there certain questions that respondents have difficulty answering or for which you question the accuracy of 

their response? Are there types of questions that you find respondents are uncomfortable answering or you 

suspect are likely to be untruthful answering?

How do you store the data? Do you use particular formats in storage?

At what stage(s) in the micro-grid development process do you conduct the surveys?

What is the cost of running the surveys?

How long do the surveys take to conduct?

How large is your survey team? Does it operate full time or as needed? Is it in house or from an external 

organization?

Do you use your surveys to estimate willingness/ability to pay? What methods do you use in surveys for estimating 

willingness to pay? Do you use this information when setting tariffs?

Questions on Survey Data Analysis

What analysis do you perform on the survey data? Who does this analysis?

Do you use surveys to estimate electricity demand before construction? If so, how?

Historically, how accurate and useful have these estimates been?

What other methods do you use to estimate electrical demand for sizing your systems?

How do you assess/estimate load growth over time and incorporate growth into system design? Do surveys play a 

role in this?

What else do you use your survey data for (e.g., marketing of appliances to customers)?

Other Load- and Site-Related Questions

What criteria do you apply when selecting micro-grid sites? Is there a minimum load density or other criteria you 

look for?

Do you use particular software in conducting these analyses? If so, what software do you use?

Do you target anchor loads? If so, what kind of anchors and why? Have these anchors led to successful micro-grid 

development? (Anchor loads are large electricity consumers that provide a reliable source of revenue)
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Table 1. Summary of Interview Questions

What criteria do you apply in selecting which customers to connect to your system?

Ongoing Monitoring and Evaluation

What data do you monitor on an ongoing basis during operation? How frequently do you collect each type of data?

Do you use the same survey(s) and approach for ongoing monitoring as you do for the survey(s) during the 

development process? If not, how do the two approaches differ (e.g., intent, questions asked, equipment used for 

survey, cost, size of team)?

What, if any, indicators of household and community impacts of your systems can you monitor using these surveys 

(e.g., impacts on quality of life, gender equity, community social infrastructure, health, education and literacy, 

income-generating, and entrepreneurship opportunities)?

Do your investors or other external stakeholders have reporting requirements that necessitate survey work (e.g., 

determining or quantifying social and economic impacts)? If so, what metrics are required, and are the current 

surveying techniques adequate for this?

Do you use any other data collection methods to validate or add to surveys (e.g., expert interviews, focus group 

discussions)?

Are the current survey content and methods adequate for your requirements? What else, if anything, is needed? 

What could be improved?
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2 Findings

All micro-grid companies interviewed performed some form of survey. These surveys span the life cycle 

of the micro-grid. Practices and attitudes toward surveys vary widely, though survey types can generally 

be placed into the following categories:

• Market research

• Site selection

• Customer applications

• Customer satisfaction

• Monitoring and evaluation.

The use of site selection surveys is universal, though the approach to these surveys ranges from very 

structured (with formal survey questionnaires and data collection) to informal site visits and open-ended 

interviews. One developer performed a large-scale market research study before market entry and later 

used the data from it for site selection purposes. Customer-level surveys, generally conducted after a site 

has been selected, are common, though less universal. These surveys are typically used to estimate 

electricity demand, screen customers, and collect data about the location of customers to aid in system 

design.

There appear to be two attitudes toward using customer surveys for demand estimation. One group uses 

customer surveys to estimate the electricity load profile before system deployment and designs a system 

accordingly. The level of detail and structure of these surveys varies widely, as do analysis methods. The 

second group is skeptical about the feasibility of estimating electricity demand with any accuracy before 

having electricity available and therefore does not invest heavily in customer-level surveys before 

construction. These developers tend to have standardized technology solutions that seek to exert more 

control over how customers use energy. These systems incorporate an ability to scale up generation, if 

necessary, once actual system loads can be observed. This is a way of mitigating the risks associated with 

oversizing systems resulting in capital expenditure for underused capacity that does not generate revenue.

During operations, most micro-grid operators collect information from their customers about their 

satisfaction with the services provided. Several developers have also conducted ad hoc surveys for 

specific purposes, such as trying to understand what electrical appliances customers are interested in 

obtaining. Most of these customer satisfaction surveys are conducted irregularly and often in an 

unstructured way. A minority of developers conduct regular, structured surveys either in person, over the 

phone, or by phone-based Short Message Service (SMS). Operators are customer-centric and focused on 

improving their services for their customers. Most operators expressed interest in monitoring the 

socioeconomic impacts micro-grids have on their customers’ households and businesses, but very little 

rigorous project specific socio-economic monitoring and evaluation is occurring primarily because of 

focus on primary business operations. Developers report little pressure from funders to provide 

socioeconomic impact data and therefore have little incentive to pursue rigorous monitoring and 

evaluation. In these eight cases, the monitoring seems to focus on finding anecdotal evidence from 

discussions with customers about how electricity services have facilitated growth in businesses and 

incomes or improved lifestyles.

In all phases of the micro-grid life cycle, survey methods were observed to be prone to several common 

sources of bias, including:
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• Social desirability bias: This form of bias occurs when respondents seek to paint themselves in a 

socially desirable light.

• Acquiescence response bias: Survey respondents tend to reply positively to questions requesting 

confirmation (e.g., questions with yes/no or agree/disagree responses).

• Primacy/recency: In closed-ended questions, respondents tend to select the first response option in a 

written survey and the last response option they hear in an oral survey.

• Question order effects: The ordering of questions can affect the way respondents answer questions.

• Misreporting: Misreporting can occur both intentionally and unintentionally, either in an attempt to 

manipulate survey results or because respondents simply do not know the answer to the question but 

are compelled to provide a response. This may also be related to social desirability bias or demand 

characteristics.

Overall, micro-grid companies seem to have similar objectives in carrying out surveys, but there is little 

consistency in approach. All study participants had reasons for approaching surveys in the manner they 

did and have accumulated valuable insights and experience that are useful to the sector. The remainder of 

this section will detail these insights and experience by survey type.

2.1 Market Research Surveys

Only one participant indicated carrying out a large-scale market research study before market entry. There 

was not a specific question about large-scale market research studies in the interview, so it is not clear 

how many other developers may have carried out similar exercises. This developer secured external 

funding to visit and survey 30 communities across 22 counties in an East African country. Data were 

collected via unstructured interviews with various local government and community stakeholders. 

Information was recorded manually on paper, along with audio recordings and photographs. This 

approach was taken to put respondents at ease and build a rapport and relationship with the communities. 

There was concern that formal, structured interviews were too impersonal and would make people 

uncomfortable. They also observed that many communities had experience with various groups passing 

through, asking questions, and raising expectations that electricity would be provided, only to be 

disappointed when electricity did not arrive, further compounding the problem of trust.

The objectives of the surveys were stated broadly to “better understand local communities and potential 

end users of micro-grid power, build relationships with government entities, and understand regulatory 

frameworks.” It was also seen as a way to demonstrate to government that they were serious about 

entering the market. Developing a strong understanding of the local context was viewed as essential by 

the microgrid companies to ensuring that local needs were affordably met. These surveys also served as 

site identification surveys, which are practiced universally in some manner.

2.2 Site Identification Surveys

Identifying communities capable of supporting a commercial micro-grid is critical to developing 

financially viable micro-grids, so all participants carry out some form of site survey to assist in site 

selection.

2.2.1 Data Collected

There are many commonalities in criteria applied for site selection between developers and therefore the 

data collected tend to be similar as well. Many developers first short-list sites for on-the-ground surveys 

using geographic information system (GIS) tools to identify areas with high population density located far 

from the existing electricity grid with reasonable road access and cellular coverage. These tools include 

GIS mapping software and applications that provide satellite imagery, such as Google Earth. Where 
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available, national electrification plans are also consulted to minimize the risk of near-term grid 

encroachment.

Before completing surveys in a community, many developers have established procedures for 

approaching regional and local authorities to present their company and development objectives and 

request an introduction or authorization to approach community leaders. This usually starts at higher-level 

local or regional government and progresses to lower-level local authorities. Other local stakeholders, 

such as utilities, may be engaged as well. These processes seem to be based both on country-specific 

regulations and local customs, which vary by jurisdiction.

Most developers reported that on-site survey teams look for several primary site factors, including 

densely populated village centers; evidence of high levels of economic activity and opportunities for 

productive electricity use; distance from the electricity grid; and practical considerations, such as road 

accessibility. Because many micro-grids use Global System for Mobile Communications-enabled smart 

meters, the quality of a mobile network is also frequently measured, sometimes using a smartphone app. 

The presence of local mobile money agents is also noted. Some developers reported taking coordinates of 

key locations, such as potential institutional and productive loads, and infrastructure, such as the nearest 

tarmac road and power line. Local leaders are commonly engaged to gauge political support for a microgrid.

Other data frequently collected include: the type and quantity of other energy technologies used in the 

community, such as diesel generators and solar home systems; proxies for wealth and income, such as the 

quality of construction of local buildings; asset ownership, such as vehicles and livestock; and factors 

affecting temporal variation in electricity demand patterns, such as the number and timing of agricultural 

seasons and, on a shorter timescale, frequency of market days. Table 2 summarizes categories of 

commonly collected data. Many developers have minimum criteria that a community must satisfy to be 

short-listed for micro-grid deployment.

Table 2. Categories of Frequently Collected Data during Site Selection Surveys

Criteria Criteria Range and Context Rationale

Distance to 

electricity grid

5–20 kilometers or more and an 

understanding of grid 

electrification plans

Grid encroachment is a risk and further distance from the 

grid lowers this risk. Also, there is a lack of clear policy in 

most locations regarding what might happen to the microgrid assets and customers if the grid did arrive.

Population 

density

Higher population density is 

better

Higher population density enables more potential 

connections within proximity to generation sources.

Community 

demographics

Number and proportion of 

households and businesses, 

vehicles, livestock, building 

construction quality, and 

electrical appliance ownership

These data can help inform the potential for initial 

electricity demand and the potential for growth.

Evidence of 

economic 

activity

Local industries, number of 

businesses, and commercial 

activity

The greater the economic activity, the greater the need for 

electricity and likelihood for sustainable demand over time.

Number of 

potential 

connections

More connections are better as 

are more connections within a 

fixed distance to town center

Developers have their own metrics, but a common aim is 

meeting a minimum number of connections within proximity 

to generation sources.

Cellular network High cellular signal strength and 

existing mobile money vendors

Developers rely on cellular communication for metering 

and collecting payments (facilitated by mobile money 

vendors) and it can also foster increased economic growth.
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Table 2. Categories of Frequently Collected Data during Site Selection Surveys

Site 

accessibility

Transportation infrastructure and 

public transit options

Good transport options often foster increased commerce 

and economic productivity, leading to increased electricity 

use. Good roads and year-round access are also 

necessary for construction and regular maintenance. 

Current energy 

technology use

Diesel generators, solar home 

systems (SHS's), solar lanterns, 

batteries, kerosene

Generators, batteries, and kerosene use suggest existing 

energy users that could readily switch to electricity if there 

were economic advantages. SHS's represent both 

competition and an opportunity to distribute excess solar to 

other loads periodically.

Potential for 

seasonal load 

demand

Seasonality of income related to

agriculture

Understanding seasonal load variation and causes can 

inform system design and impact revenue consistency.

Productive 

loads

More productive loads are better 

and can improve the overall 

business model of the micro-grid 

Many productive loads will benefit from local electricity 

availability. Productive loads are high consumers of 

electricity and will also increase the disposable income in 

the community to enable further electricity use.

2.2.2 Collection Methods

Although there is some consistency in the type of data collected during site surveys, the method of 

collection and whom the data are collected from varies significantly. Two general approaches to 

collection emerged from the interviews with developers, and their characteristics are summarized in Table 

3. Some developers have a formal, consistent set of questions that are collected on all sites - while others 

take a more informal approach. The informal approach may lead to respondents feeling more at ease and 

thus providing more information than they might otherwise, including information that might not be 

easily captured in a structured survey. However, this approach comes with the caveat that the collected 

data may not be so readily comparable between different communities. Both approaches have their own 

merits, and most developers incorporated some elements of each.

Table 3. Collection Methods

Type Method Rationale

Formal survey:

consistent set questions 

for every respondent

Smartphone or tablet: collect 

photos and videos, upload to 

cloud, sort data

Efficient, consistent data for subsequent 

analyses and comparison while providing 

coordinates, cell strength, and photos

Manual notes or audio recordings, 

collect photos and videos

Consistent data for subsequent analyses and 

comparison

Informal survey: oneon-one, free-flowing 

conversation

Manual notes or audio recordings, 

collect photos and videos

Likely to keep respondents at ease but can 

result in different types of information or data; 

not necessarily readily analyzable

Only one of the developers has a full-time dedicated survey team. Most developers conduct surveys using 

employees whose primary responsibilities lie elsewhere. Some hire freelance surveyors to assist 

employees in conducting surveys. Multiple developers cited concerns relating to surveyors. The cultural 

and linguistic diversity found in many African countries presents challenges, particularly when surveyors 

are not familiar with the cultural context and do not speak the local language. This can lead to 

misunderstood questions and answers or to questions phrased or posed in ways that make respondents 

uncomfortable. Several forms of bias can occur in survey data, which can be exacerbated by untrained 

enumerators. Some of the pitfalls observed in collecting survey data are presented in the section on 

Lessons Learned under Customer Application Surveys. These include biases related to social desirability 
9

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(when respondents provide answers they view as socially desirable, such as exaggerating one’s education 

in the presence of peers), electricity demand characteristics (when respondents infer the purpose of 

questions and answer in a way they believe will benefit them such as answering questions in a way they 

believe will increase their likelihood of receiving an electricity connection), and acquiescence (when 

respondents tend to agree with statements from the interviewer). One developer expressed strong 

concerns about interviewer bias related to acquiescence. Well-designed surveys and trained enumerators 

can help mitigate these effects.

2.2.3 Logistic and Financial Considerations

Running surveys in remote, often poorly accessible villages in regions with diverse cultural and linguistic 

communities can be costly and complex. There are often several layers of stakeholders that need to be 

consulted before entering a community to administer surveys. As an example, several developers 

described first having to approach regional government officials to obtain permission to engage with 

district officials who were also gatekeepers to approaching village leaders. These cost and logistical 

factors influence how developers approach surveys.

2.2.3.1 Cost of Running Surveys

Not all developers track the cost of running their surveys and, due to the informal and opportunistic 

approach that some developers take, it may be difficult to allocate costs specifically to survey activities. 

However, participants with more structured and formal survey programs were able to provide some cost 

estimates. Developers report that the majority of costs associated with running surveys are related to 

logistics, particularly transportation. The cost of labor is a relatively small portion of the total cost.

One of the developers in East Africa with a more sophisticated survey program has a dedicated survey 

team. The cost of a site survey was reported to be approximately $100-$150 per site. This cost reflects the 

practice of using a vehicle and driver to transport the survey team because site surveys are shorter in 

duration than customer surveys. 

Other developers reported using private transportation for surveys, with one developer using air travel in 

some instances. Few developers have dedicated survey teams, while some rely on part-time contract 

workers who are not employees. Most developers are still small, lean organizations; and therefore, 

employees conducting surveys don’t have specialized training.

2.2.3.2 Time Required for Surveys

The time required to complete site surveys varies depending on remoteness of the site and travel time. 

Most developers describe surveying several communities in a region at the same time to reduce the travel 

time per site. Before surveying communities, local government and other stakeholders at a regional level 

should be consulted. This regional work does not need to be completed by a full survey team, but it still 

increases the amount of time required overall to complete site surveys. Once on the ground, developers 

report surveying 1–3 sites per day, with those conducting more detailed surveys or samples of customer 

surveys taking longer to complete.

2.2.3.3 Whom Do Surveys Target?

Site surveys tend to target community leaders and, at times, a representative sample of the general 

population within the community. Surveys may also target potential productive users of electricity. 

Developers differed in how they target potential customers to survey during site surveys. Most developers 

who also interview individual customers take a two-phased approach. They conduct site surveys first, and 

they do not return to the site to interview individual potential customers until after they create a short list 

to identify the most promising sites. One developer stated that, for particularly promising sites, customer 

surveys could take place at the same time as the site visit, though this is not the standard practice. A 
10

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couple of developers stated that they perform customer surveys for a sample of about 10% of the 

population during the site survey with the intent that it is roughly representative of the population. 

2.2.3.4 Timing in Development Process

Analysis of GIS data to identify promising regions and communities is typically the initial step in site 

identification. The GIS screening narrows the list of potential sites. Site surveys are often the next step in 

the development process and contacting people in the community to conduct the survey connects the 

developer to the community.

2.2.4 Analysis Techniques

The initial GIS data combined with site survey data, whether obtained via formal survey or informal 

conversation, provide developers with critical pieces of necessary information to determine if a site 

should be developed. None of the developers pointed to a formal analysis technique to make final siting 

decisions. All pointed to combining the collected data with more subjective data and their experienced 

judgment to arrive at decisions to move forward at particular sites.

The collected site information combined with other development information obtained through discussion 

with government officials, regulators, investors, financiers, and other stakeholders enables the 

experienced developer to analyze and weigh the potential suitability of one site compared with another. 

Some of the collected data will have minimum thresholds for a developer, but there will also be subjective 

weighting assigned to numerous factors, such as comparing sites based on their perceived level of and 

potential for economic activity, which is assumed to be tied to electricity consumption and ability to pay 

for energy services. Final siting decisions are made combining the more objective data collected with the 

more subjective developer experience and intuition.

2.2.5 Lessons Learned

There is not a large enough sample of micro-grid sites with available site survey and assessment data to 

be able to draw firm conclusions on the relative performance of different approaches to identifying 

successful sites. However, each developer established their respective site survey methods based on their 

own rationale and micro-grid development experience. Approaches span a spectrum from very formal and 

structured to informal and unstructured. Reasons for taking a less formal approach include skepticism in 

the accuracy of survey data, resource constraints, and a belief that structured surveys are too impersonal 

and make respondents uneasy. Some developers taking an informal and unstructured approach believe 

that this method makes respondents more comfortable and helps build a relationship with the community, 

which is an important, though not necessarily quantifiable, micro-grid development factor. Several 

developers have started with unstructured approaches and as they have grown, they have transitioned to 

more structured and sophisticated data collection and analysis. This could indicate that as scale increases, 

developers see more need and value in standardized approaches that allow them to more easily scale. 

The downside to the informal approach is that data collection is not uniform, which makes it difficult to 

analyze in a systematic framework and apply lessons to future projects. Analysis tends to become more

subjective and can be influenced by analyst bias. More structured surveys provide developers with a 

common set of data on which to judge and rank sites. They can then use a more systematic analysis of 

data to come to more objective conclusions about which types of sites tend to be successful and the 

factors that determine that success. Both approaches have their merits, and developers operate with 

elements from both approaches, though they may favor one over the other. A balanced approach to collect 

data may permit objective analyses while respecting the human elements of the development process.
11

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2.3 Customer Application Surveys

Developers sometimes perform customer application surveys with individual prospective customers 

before constructing a micro-grid. These surveys are less universally performed than site surveys; 

however, two developers do conduct structured, formal surveys of all potential customers. Others survey 

only a sample of potential customers, and some do not perform customer surveys at all. The primary 

purpose of these surveys tends to be to screen customers for connections, to estimate demand for 

electricity, and to collect information used for system design. One developer indicated that it had 

conducted customer surveys to serve as a baseline for future impact assessment, though follow-up surveys 

never occurred.

2.3.1 Data Collected

The two developers that conduct formal, structured customer surveys collect similar data, though the 

timing of the surveys differs. Information is collected about the nature of the connection (whether 

business or residential) and the coordinates of the building to be connected. For residential connections, 

data are collected on household demographics, such as the number of residents in different age groups, 

occupation and sources of income, assets, education level, the size and quality of construction of the 

home, modes of transportation, and current energy uses/sources. Business connections are asked 

questions about the nature of their business, current energy uses/sources, income, assets, and the quality 

of construction of the business premises. One of the developers also asks about electrical appliances that 

potential customers intend to acquire.

Those developers with less formal customer surveys tend to seek to identify the type of connection, 

general household demographics, current energy sources, and end-uses. However, this information is not 

always collected systematically and may target only a sample of potential customers. One developer 

reported sampling a subset of customers and taking a physical inventory of electrical appliances and 

energy sources. This developer operates in a region where using diesel generators is common and, 

therefore, targets customers already accustomed to using electrical energy.

2.3.2 Collection Methods

Developers report using survey teams of 2–3 people for customer surveys. Only one developer reported 

having a dedicated survey team. Other developers use non-specialized employees to conduct surveys, 

though one developer acknowledged the advantage of having a team trained specifically to carry out 

survey work. A couple of developers reported carrying out surveys in cooperation with external 

organizations that provided enumerators, though these were not customer application surveys.

The majority of developers carrying out customer surveys report using smartphone or tablet apps to 

collect data. Surveys are designed on a computer and loaded into an app that guides enumerators through 

the survey and provides a platform to enter open responses or select from predetermined response options. 

Data are stored locally on the device and uploaded to the cloud later. Data can then be downloaded from 

any internet-connected device in tabular form. 

Some survey tools are also capable of automatically logging coordinates and cellular signal strength, 

which is used during system design. Three developers reported collecting data with manually written 

notes or voice recordings. One has abandoned this practice, and another plans to transition to a digital 

survey tool. The developer that did not report a transition to digital survey tools expressed concern that 

such formal survey tools make respondents uncomfortable and detract from building relationships with 

communities. Handwritten notes and recordings are later transcribed, digitized, and stored electronically.
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2.3.3 Logistic and Financial Considerations

As with site surveys, the remote location of micro-grid sites presents logistical and cost barriers. Cost of 

collection, weighed against the value that developers place on the data collected, has deterred some 

micro-grid companies from collecting customer-level data.

2.3.3.1 Cost of Running Customer Application Surveys

As with site surveys, most developers do not track the costs of their customer application surveys. Costs 

are driven more by logistics than the cost of labor, which is relatively low. To keep costs low, some 

developers report using contract workers to conduct surveys, supervised by regular employees.

The East African developer with a dedicated survey team reports the cost of customer surveys at $3 per 

customer. Customer surveys that target all potential customers can take several days to complete. The 

survey team of 2–3 surveyors travels by public transportation for customer surveys. This adds significant 

travel time but, because labor costs are low, this is less costly than paying for private transportation. 

Typically, several communities in a region would be targeted for survey on the same trip. Through 

training to improve the efficiency of surveyors, they report reducing the cost of customer surveys from 

$10–$15 per customer initially to only $3 at present. Another developer with a formal survey program 

reported customer survey costs of $200 per site, though the actual number of customers surveyed was not 

clear.

2.3.3.2 Time Required for Surveys

The developers with formal customer survey programs report similar time requirements: about 30 minutes 

per customer. There is a desire to reduce the length of surveys by assessing which questions produce the

most useful information to reduce time and cost requirements. Some developers report that finding 

potential residential customers at home to complete surveys is challenging. Therefore, as a time-saving 

measure, a developer reported collecting contact details of potential customers when the survey team 

arrives in the community to make an appointment to conduct the survey.

2.3.3.3 Whom Do Surveys Target?

Only two of the developers—those with formal surveys—attempt to conduct a census of potential 

customers. Other developers rely on a representative sample of the population of potential customers to 

reduce survey time and cost while still obtaining meaningful data. Productive users may be targeted with 

a different survey to better understand their power needs.

2.3.3.4 Timing in Development Process

In general, developers conduct customer application surveys after carrying out a site survey and shortlisting the community for a micro-grid. This avoids wasted costs in surveying communities that are not 

targeted for development, but it does require an additional trip to the site. Two developers report 

conducting a sample of customer surveys during the site survey, with one making on-the-ground 

judgments about whether surveying customers is worthwhile. The two developers with formal surveys 

differ slightly in approach. One developer conducts full customer application surveys in a single visit. The 

other conducts a short application survey before construction, asking only for basic information such as 

the connection location and type, names, and contact information. More comprehensive surveys are 

conducted during the installation process. In general, there are different points of view on when to 

conduct customer surveys relative to the timing of decisions to build a micro-grid in a community. 

Customer application surveys are expensive to conduct; however, they can provide valuable information 

on the viability of a site. If developers conduct customer surveys after deciding to build at a site, good 

sites may be overlooked. If they conduct surveys before the decision, money may be wasted surveying 

sites that are not selected. Surveying a sample of customers during site visits presents a middle ground.
13

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2.3.4 Analysis Techniques

The sophistication of the analysis performed on customer survey data varies depending on the type and 

depth of data collected. Developers collecting formal survey data have both conducted quantitative 

analysis relating customer data to subsequent electricity consumption to ascertain which customer 

characteristics are correlated to electricity demand. They can also use these techniques to make 

quantitative predictions. Developers with less comprehensive surveys tend to take an inventory-based 

approach, whereby electricity demand is estimated by making assumptions on which appliances 

customers will use, their power ratings, and their duration of use. These assumptions may be based on 

data collected from potential customers on their current and intended use of electricity. For developers 

with operating data, historical energy use from existing customers may inform these estimates. 

Developers and recent studies have shown that customers are not good at predicting their own energy use 

behavior; as a result, the inventory method tends to overestimate electricity demand (Blodgett et al. 2017; 

Hartvigsson and Ahlgren 2018).

Customer coordinates are used to design the micro-grid reticulation network. Some developers estimate 

willingness and ability to pay using information reported by customers on current energy expenditure, 

though the methods applied are not rigorous and involve some amount of experience and intuition. 

Analysis performed by those using less formal survey methods tends to be more qualitative. Those that do 

not perform customer surveys expressed skepticism in the feasibility of predicting electricity demand

using survey data. Rather than attempting to predict electrical load, these developers tend to exert more 

control over how customers can use power and design their systems to be scalable to meet larger-thanexpected electrical load growth.

In addition to estimating customer electrical demand, some developers use customer surveys to determine 

which customers to connect to the micro-grid. Micro-grid companies typically do not charge customers 

the full cost of connecting them to their system in an up-front connection fee. This means that they must 

recover this cost over time through tariffs charged for energy use. Connecting customers that use little or 

no energy therefore represents a financial loss. Approaches to customer screening vary. Generally, there 

is also a threshold distance beyond which developers will not connect customers. This threshold may be 

extended for customers if their expected electricity consumption justifies the additional cost of 

connection. One developer reported connecting all customers within range of the micro-grid. Four 

developers stated that they connect any customer that can demonstrate ability to pay by paying a 

connection fee or prepaying for a month of electricity service. Developers with more sophisticated 

surveys and analysis techniques have more nuanced criteria, particularly for customers that are more 

expensive to connect. Developers base the decisions on characteristics that they identified through 

surveys and electricity consumption data for existing customers that they correlated with high demand for 

electricity. These developers also charge upfront connection fees.

2.3.5 Lessons Learned

Developers tend to fall into two camps when it comes to using customer surveys to estimate electricity 

demand. Those using sophisticated survey tools apply quantitative methods to estimate demand and 

design systems to meet this demand. On the opposite end of the spectrum, developers that are skeptical 

about the ability of surveys to predict demand attempt to exert more control over electricity use and install 

minimal generation capacity initially with the ability to scale up, if necessary, after directly measuring 

demand. Each approach has its merits and limitations. Exerting control over consumption restricts the 

ways customers can use energy and installing capacity in phases will likely be more expensive than a 

single installation. On the other hand, this approach limits the risk of oversizing the system and reduces 

spending on unused capacity. Survey-based demand forecasting tools will never produce perfect 
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predictions, but they help developers design systems capable of meeting customer needs from Day 1. This 

comes at the cost of conducting detailed surveys.

There are several pitfalls to conducting surveys. Using inexperienced enumerators can lead to surveyor 

bias. Variances in how surveyors pose questions can lead to different interpretations of questions and 

different responses. Cultural practices and norms also come into play during the interview. Developers 

shared several anecdotes about instances of survey bias. For example, one developer noted that some 

male survey respondents are not comfortable being surveyed by females. Further, language barriers may 

be present in linguistically diverse African countries. Some respondents were observed demonstrating 

social desirability bias, exaggerating their education or social status, particularly in the presence of a 

spouse or peers. Others were observed providing false responses to answers based on their interpretation 

of the question’s purpose. Respondents may also hide assets if they fear they may be used as collateral or 

exaggerate income and intended electricity use, because they believe it will improve their chances of 

receiving a connection.

Several developers also reported that respondents had difficulty answering questions with quantitative 

answers. Income, for example, is often not in the form of cash for subsistence farmers. It is also seasonal, 

based on agricultural cycles, and varies from year to year. Most farmers do not have a steady income and 

do not keep records. Expenditures are sometimes used as an alternative data point to income; however, 

respondents often have difficulty estimating these quantities as well. Multiple developers reported 

assisting respondents in making these estimations. For example, in trying to estimate expenditure on 

kerosene, an enumerator may ask how frequently a respondent purchases kerosene and in what quantity. 

Local prices for kerosene are easy to find, and with this information, the surveyor can estimate monthly 

expenditure on kerosene.

Developers must carefully phrase questions about intended electricity use to avoid aspirational responses. 

Respondents tend to list appliances that they would like to have rather than those that they could 

realistically acquire. They may simply lack information on the cost of appliances and, therefore, cannot 

accurately judge their ability to acquire them. One developer that does not conduct customer surveys 

expressed concern that when respondents do not understand questions, the surveyor will infer or suggest a 

response to complete the survey, leading to acquiescence bias.

2.4 Customer Satisfaction Surveys

All developers collect data after the start of operations on customer satisfaction, but few do so 

systematically. Regardless, the micro-grid developers interviewed demonstrated a customer-centric 

approach to their business. In contrast to many national utilities, micro-grid operators engage with their 

customers more frequently to provide high-quality service and seek out opportunities to enable customers 

to find more uses for electricity.

2.4.1 Data Collected

Most operators described ad hoc interviews to obtain specific information and informal discussions with 

customers about their satisfaction with the service received, how electricity access has affected their 

business and lifestyle, and how electricity services could be expanded to meet customer needs. Several 

developers have carried out surveys to obtain feedback from customers for a specific purpose. For 

example, several developers solicited information from customers on appliances they would like to 

acquire and their interest in participating in programs offering electrical appliances on credit. Developers 

conducting comprehensive customer surveys also draw on data from customer surveys about desired 

appliances to target such offers.
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Two operators described a systematic and ongoing customer satisfaction survey program. One operator 

has two separate surveys: one is performed shortly after installation to request feedback on the installation 

process via SMS with subsequent monthly SMS surveys carried out asking customers to rate, on a scale 

from 1–5, their satisfaction with service received, whether they would recommend the company to others, 

the value received for money paid, and the reliability of electricity service. In the second survey, 

customers are asked to select from a list of barriers that prevent them from using more electricity and how 

their customer experience could be improved. The other operator using regular surveys collected 

information at the point of sale with an agent asking questions and registering responses on a smartphone. 

The operator asked customers what they like about the service received, what new services and appliances 

they would like to obtain, and how they feel about pricing.

2.4.2 Collection and Storage Methods

The operators collecting regular customer satisfaction data use more automated methods of data 

collection. One operator uses SMS surveys, and the other collects data via a smartphone app with data 

entered by a local agent at the point of sale. These data are aggregated via the mobile phone network and 

stored electronically.

Multiple operators described using regular village meetings as a platform to communicate and obtain 

feedback from customers. When more specific information is sought, some developers call customers on 

their mobile phones. Those operators using informal methods of data collection are opportunistic 

regarding when they collect data and they use site visits for other purposes to engage informally with 

customers. One operator reported sending questions to local operators to ask informally in the community 

when specific information is desired.

2.4.3 Logistic and Financial Considerations

Operators did not report specific costs for customer satisfaction surveys. Those operators taking a more 

opportunistic approach only incur a time cost. Those using mobile phone technology incur costs of data, 

SMS, and voice calls. Relative to site and customer surveys, the cost of collecting customer satisfaction 

data is low. Using mobile phone technology to collect data also reduces the logistic complexity of data 

collection, though the response rate may be lower than for in-person surveys.

2.4.4 Lessons Learned

Many of the operators interviewed only have a small number of pilot sites in operation, and therefore 

have not yet fully developed customer satisfaction programs. However, operators did express interest in 

developing tools to track customer satisfaction in a more systematic way. Developers that have already 

developed such tools have had success administering these surveys using mobile phone technology, be it 

via SMS, administered by a local agent using a smartphone app or by voice call.

2.5 Project Specific Socioeconomic Monitoring and Evaluation 

Surveys

Many micro-grid utilities tend to be socially motivated enterprises. Although many seek to earn a return 

on investment for their services, they also aim to positively impact the communities in which they 

operate. All developers expressed an interest in tracking the socioeconomic impacts of their services; 

however, no developers have established a formal self-directed nor independent socioeconomic 

monitoring and evaluation (M&E) program. A common view expressed is that although they would like 

to carry out such work, ensuring high-quality service and return on investment is a higher priority and the 

costs vs. benefit of carrying out socioeconomic M&E can be too high. Further, although common in some 

instances, in this limited sample size the operators did not report socioeconomic M&E requirements from 

their funders or other stakeholders. However, multiple developers said that they would be interested in 
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receiving support to carry out project specific socioeconomic M&E work, and they recognize there may 

be some value in collecting these data both for their own purposes and as a means of attracting additional 

investment from impact investors. The operators do, however, monitor business metrics such as the 

number of consumers, average revenue per user (ARPU) and electricity consumption. These metrics 

could be correlated to socioeconomic impacts and used as proxies.

2.5.1 Surveys and Productive Use

Most developers described targeting and attempting to create productive users of electricity. One 

developer is working with a nonprofit organization to provide training and financial support to local 

entrepreneurs to enable them to use electricity productively. During site and customer application 

surveys, several developers report administering surveys specifically for productive users. These surveys 

focus on the technical requirements of productive loads. This information is then used during system 

design to ensure that the micro-grid is designed to meet these requirements.
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3 Surveys for Electrical Load Prediction

Effective surveys can provide very useful data for statistical analysis as well as insightful anecdotal 

information. Though the survey of developers was composed of a relatively small sample (eight 

developers), some objectives were to: learn about their survey approaches, discover how they use the 

survey data, and see if there are approaches on how to improve the surveys themselves or the reliability of 

energy consumption predictions based on statistical analyses of the data. To frame this, it may be best to 

look at larger-scale customer surveys that have been done and the statistical analyses approaches that 

have been employed to extract meaningful data for predictions from them.

3.1 Customer Surveys in Tanzania

Survey data are often used as a basis to predict the electrical load in potential micro-grid recipient 

communities. However, the methods of analysis vary significantly from developer to developer. A 

common approach is to take an inventory of current and expected future electric loads and consumer 

reported use/expected use patterns after connection. Blodgett et al. (2017) found this to result in large 

overestimates of consumption. It is not surprising that users who have never had a connection to 

electricity would have a difficult time predicting their own consumption. Further, Hartvigsson and 

Ahlgren (2018) found that consumers who already have a connection have difficulty estimating their 

consumption using the same method.

Other developers don’t make quantitative predictions of electricity demand with their survey data; rather, 

they use customer characteristics to screen or classify customers by expected level of demand. A minority 

of developers have developed statistical models to relate pre-electrification customer characteristics, 

collected with surveys, to post electrification energy consumption. For these methods to be effective, 

surveys must capture customer characteristics that are correlated to electricity use. To understand which 

variables are useful in predicting electricity demand, survey and electricity consumption data were 

analyzed from 1,044 micro-grid customers in Tanzania.

The survey data were collected before micro-grid deployment using in-person interviews with potential 

micro-grid customers. Data were entered using a smartphone-based survey app, and questions were asked 

in Swahili by local enumerators. The data, summarized in Table A-1 in the appendix, includes questions 

about household composition, business activities, energy use and appliance ownership, household 

economic activities, assets and income, and transportation mode. Variables indicated by a category 

followed by “Other Low Frequency” are responses to a question with a categorical response for which the 

selected response represented less than 5% of total responses. Responses falling below the 5% threshold 

were grouped for building statistical models, because there is not sufficient data to estimate individual 

coefficients.

An indication of which variables are related to electricity demand can be obtained by looking at how 

survey responses correlate to energy consumed. Figure 1 shows the predictors with the top 15 highest 

correlation with average daily electricity consumption in the first 90 days since connection to the microgrid. Positive correlation suggests for categorical variables that the presence of this characteristic is 

associated with higher electricity consumption. For quantitative variables, positive correlation suggests 

higher values of this variable tend to be associated with higher electricity consumption. Negative 

correlation suggests the opposite effect. Those reporting to have seasonal income fluctuations are 

positively correlated with electricity consumption, as are being a longtime resident in the community and 

occupying a structure made from well-built concrete or wood (which is used as a proxy for wealth). 

Transportation modes also feature strongly with positive correlation to electricity consumption; however, 

because all the possible responses are positively correlated, transportation modes do not provide 

significant information beyond the correlation that people with transportation modes other than walking 

use more electricity. Sleeping patterns also seem to be correlated with electricity consumption, which is 
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related to how much time people are active during the night when people tend to use electricity for 

lighting and entertainment. The strongest negative correlation is with falling into the lowest household 

income category. However, even higher reported income is negatively correlated to electricity demand. 

This is likely due to the fact that this income was only recorded for households, which generally use less 

energy than commercial customers. Commercial customers will therefore be recorded as not belonging to 

any of the income categories.

The highest average consumption among households are those for which no income category was 

assigned and those with income between 500,000 Tanzanian shilling (TSH) and 1 million TSH per year 

(approximately $225 United States dollars [USD] to $450 USD). It should also be emphasized that 

correlation does not imply causation, and high correlation does not necessarily mean a variable will be 

valuable for prediction. Variables are correlated not only with electricity consumption but also with one 

another, making it difficult to untangle which variables directly influence consumption and those that 

correlate to demand indirectly.

Figure 1. Correlation coefficients between survey variables and daily electricity consumption in 

first 90 days since connection to the micro-grid.

Note: Household (HH) income is for households only (1 USD = 2,250 TSH).

As noted, correlation by itself doesn’t provide a full picture of which customer characteristics are helpful 

in predicting electricity demand. Many of the data collected are correlated with one another. Statistical 

models can help address this issue. Table 4 shows the variables selected using a Least Absolute Shrinkage 

and Selection Operator (LASSO) Poisson regression to model the relationship between electricity 

consumption in the first 3 months since connection to the 132 variables described in Table A-1 in the 

appendix, plus controls for tariff structure and price. The LASSO regression has the property that it 

performs variable selection, selecting the subset of predictors that produce the best predictions and using 

cross-validation to determine the model-tuning parameter (Tibshirani 1996). Table 4 shows the variables 

selected using LASSO regression to predict electricity demand for newly connected micro-grid customers 

as well as the sign of the coefficients. A positive coefficient means that the variable is positively 

correlated with electricity demand, whereas a negative coefficient shows negative correlation. Energy 
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sources, transport modes, pre-electrification appliance ownership, building type, connection class, and 

business type feature strongly.

Table 4. Variables Selected in LASSO Regression Model Including the Sign of Model 

Coefficients

Variable Coefficient Sign

Diesel use: heat +

Transport: other low frequency +

Transport: boat +

Gasoline use: electricity generation +

Business type: bar +

Building type: wood +

Pre micro-grid appliances: other low frequency +

Pre micro-grid appliances: high-watt TV +

Pre micro-grid appliances: light bulb +

Pre micro-grid appliances: low-watt TV +

Business type: other +

Business connection +

Pre micro-grid appliances: other +

Firewood use: cooking -

Respondent employment: self-employed agriculture -

Transport: bicycle -

Energy source: firewood -

Business type: restaurant -

Home connection -

Another method to analyze which variables are useful in reducing prediction error for electricity demand 

is the random forest model. Random forest models are tree-based, ensemble-learning techniques (Breiman 

2001). Ensemble-learning techniques combine multiple learning algorithms to improve predictive 

performance. Variables in a random forest model can be ranked by “increase in node purity,” which is a 

measure of how much predictions improve by including each variable in the model (Hastie et al. 2008). 

Figure 2 illustrates the most important variables for demand prediction using the random forest model as 

measured by increase in node purity. Here, importance is measured by the reduction in prediction error 

resulting from each variable. Like the LASSO, transport modes, pre-electrification appliances, 

connection/business type, and building type rank highly. The LASSO model performs better in predicting 

mean electricity consumption in the first 90 days after connection compared with the random forest model 

as measured by mean squared error. However, the random forest model is nonlinear and does a better job 

at identifying customers with high consumption, which is often an objective of customer surveys. By 

incorporating variables identified from both models, we balance the objective of accurate predictions and 

identification of high-use customers.
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Figure 2. Random forest variable importance for electricity demand prediction.

Note: Higher importance indicates high reduction of prediction error from using the variable in the model.

Other work by Lee (2017), using data from 600 micro-grid customers in Tanzania and data from a survey 

containing 16 questions, found that building type, mobile phone expenditure, and customer type are 

significant predictors of electricity consumption.

Overall, our analysis suggests that questions on the following subjects are useful in predicting electrical 

loads for potential customer demand:

• Customer class (home, business, home/business, public premises): Businesses and home/businesses 

show higher potential energy usage.

• Nature of business: Not all businesses indicate a potential higher energy use profile, though bars 

(taverns) tend to show more energy use while restaurants show less.

• Employment status: Only those self-employed in the agriculture space show a negative correlation to 

energy usage.

• Current source of energy and uses: Generally, use of higher capacity electrical energy sources would 

provide an initial indication of higher electrical energy use, though only diesel power generation was 

identified as being a good indicator of higher energy use.

• Current mode of transport: Generally, the more advanced the transportation mode, the higher the 

energy use, boats, cars, and other transportation modes indicate higher energy use as compared with 

walking. It is possible that more advanced modes of transportation serve as a proxy for income or 

wealth. 

• Appliances owned before micro-grid connection: The use of larger energy use appliances, as 

expected, provide a good indication of higher energy use following micro-grid interconnection.

• Building construction materials: Higher quality of construction materials is related to higher energy 

use.

• Mobile phone airtime spending: Although a direct correlation is not available, airtime spending is an 

indicator of higher disposable income, which would indicate the willingness to spend on additional 

services that were perceived as having value. Name
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This set of characteristics could form the basis of surveys, with the objective of selecting high 

consumption electricity consumers or building models to predict electricity demand before connecting 

new customers. Table 5 presents a proposed set of survey questions that could be used in this manner to 

form the basis of customer screening surveys.

Table 5. Proposed Survey Questions for Electrical Load Estimation

Blue indicates correlation with high consumption, while red indicates correlation with low 

consumption.

What is the nature of this connection?

Home, Business, Home/Business, Public Premises

If this is a business, what business activities are you involved in?

Restaurant, Bar, Guest House/Hotel, Shop, Phone Charging, Other (could specify further options or leave for free 

entry)

If this is a home, what is the employment of the primary income earner in the home?

Self-Employed Non-Agriculture, Self-Employed Agriculture, Employee, Unemployed, Other

What are your current sources of energy?

Firewood, Battery, Diesel, Petrol, Kerosene, Propane, SHS

What modes of transportation do you own?

Bicycle, Motorcycle, Car, Boat, Other

What electrical appliances do you already own?

Lights, Phone Charger, Radio, Television, Sound System, CD/DVD Player, Other

What material is the house or structure where you are seeking a connection made from? (could be observed 

rather than asked)

Brick, Crumbling Concrete, Well-Built Concrete, Wood, Other

In a typical week, how much money do you spend on mobile phone airtime?
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4 Best Practices

This section of the report presents best practices for survey methodologies applied to micro-grids, 

drawing practical insights from the experiences of the developers that participated in this study. This 

section is divided into three survey phases: design, implementation, and analysis.

4.1 Survey Design

Careful survey design is crucial to ensure that questions are phrased in a way the respondents interpret 

correctly and provide the developer with the desired information. This starts with clearly defining survey 

objectives, identifying data required to achieve these objectives, and crafting good questions that avoid, as 

much as possible, common sources of response bias. 

This report and previous research indicate that taking the time to properly develop a survey, including the 

consultation of professionals in survey development, and using staff specifically trained in proper survey 

techniques is very likely to improve the results and cost-effectiveness of the entire process.

4.1.1 Writing Questions

Survey data are less useful when respondents do not understand and respond to questions in an accurate 

and consistent manner. Survey questions should be written in simple, precise, and non-technical language 

that respondents will interpret accurately and consistently. It is important that questions be specific about 

what they are asking to avoid ambiguity. For example, in asking about income, it may be unclear to 

respondents if non-cash income or food farmed for self-consumption is to be included. The question 

should be specific in defining the information that is being requested. 

A good practice includes closed-ended questions that permit respondents to select answers from a closed 

set of possible responses and require a response. The question can be partially opened by including an 

“other” response option and free entry of text where none of the predefined responses is a match. This 

makes it clear that the data are not missing, though a response to the question did not fall under any of the 

predefined options. Where possible, questions should be written and asked in the language in which the 

respondent is most comfortable and pretested with trained enumerators and respondents from the target

population.

Pretesting is the process of trying out survey questions to ensure that they are understood and interpreted 

as intended by respondents. Although this requires an additional investment in time and finances, it is a 

small investment compared with the cost of finding out after a large-scale survey that a question was not 

well-thought-out and did not provide reliable data. Effective survey questions have a higher likelihood of 

being reused in subsequent surveys, so the initial expense can yield significant dividends over time.

4.1.2 Sources of Bias

There are various forms of response bias that can result in inaccurate survey responses. Many of these 

forms of bias were reported by developers during interviews. Pretesting can be used to identify and 

mitigate response bias.

4.1.2.1 Social Desirability Bias

Several developers reported social desirability bias. This form of bias occurs when respondents seek to 

paint themselves in a socially desirable light. One developer noted that the extent of this bias is dependent 

on the presence of peers and family when the interview is being conducted. The developer observed that 

male heads of household may exaggerate their level of education, for example, if their wife is present 

during the interview. Conducting interviews in a private setting may help reduce social desirability bias. 
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Written surveys also afford a level of privacy and anonymity that could reduce bias (Lavrakas 2008). In 

practice, written surveys may not be a viable option in areas with low literacy levels.

4.1.2.2 Acquiescence Response Bias

Acquiescence response bias occurs when respondents tend to reply positively to questions requesting 

confirmation. For example, asking if customers are satisfied with the level of service they receive may 

have a different result than asking customers if they are unsatisfied. One developer interviewed expressed 

concern about the prevalence of acquiescence response bias. In general, the best way to avoid this form of

bias is to avoid using questions with yes/no or agree/disagree responses. In the former example, the 

question could instead ask customers to rate their experience on a scale of 1–5, with 5 being excellent and 

1 being poor (Lavrakas 2008).

4.1.2.3 Primacy and Recency Effects

Closed-ended questions—those with a finite set of responses—are subject to primacy and recency effects. 

The mode of delivery of the survey affects which of these effects are prevalent. In orally delivered 

surveys, where response options are provided as a list, respondents tend to select the options they heard 

most recently, i.e., those at the end of the list. This is called the recency effect. On written surveys, where 

respondents read the options, the first answers on the list are more likely to be selected. This is called the 

primacy effect. Where questions do not have a natural order, randomizing the order of options across 

surveys may mitigate this effect (Lavrakas 2008).

4.1.2.4 Question Order Effects

The order in which survey questions are asked can have an effect on the responses provided by survey 

participants. Prior questions provide the context and mindset in which subsequent questions will be 

answered. Question order effects can be difficult to anticipate but can be studied using pretesting 

(Lavrakas 2008). The Harvard Program on Survey Research suggests that it is good practice to put easy 

questions at the beginning of the survey and save more difficult or sensitive questions, such as those 

about income, for the end of the questionnaire (Harrison 2007). 

4.1.2.5 Misreporting

Several developers reported issues with respondents providing inaccurate responses as a way of 

manipulating the survey because of their perception of the purpose of the survey. For example, 

respondents who fear their assets will be used as collateral may underreport their quantity or value. On the 

other hand, respondents who believe their likelihood of receiving an electricity connection will be 

affected by their survey responses may exaggerate their income, assets, or other characteristics that they 

feel will improve their chances.

Misreporting may also occur because respondents simply do not know the answers to questions. A 

common concern expressed in interviews with developers was that respondents have a very difficult time 

giving accurate quantitative responses to questions about income, expenditures, and energy use. 

Respondents may not keep track of these values, or it may simply be unclear what is being asked. For 

example, does income refer only to cash income, or does the value of crops harvested by subsistence 

farmers for their own consumption count? It is important to craft narrow questions that will be interpreted 

uniformly by respondents. Several developers have reported that they find it useful to break down 

questions about quantitative values, such as income or energy expenditure, into smaller pieces to help 

respondents estimate accurate answers. An example of walking through the steps to estimate expenditure 

on kerosene was provided in the previous section on Customer Application Lessons Learned.
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4.1.3 Survey Length

Several developers expressed concerns about respondent fatigue resulting from long survey interviews 

during which respondents may become bored or tired of answering questions. This can cause respondents 

to provide incomplete or short responses in an effort to bring the exercise to an end. Respondent fatigue is 

exacerbated by complex, repetitive, or open-ended questions. Further, longer surveys are more expensive 

and time-consuming to administer. One of the reasons that some developers have deployed long surveys 

is that they do not know exactly which information will be useful for their objectives, such as selecting 

sites, screening customers, and estimating electricity demand. Some developers have now collected 

enough data to start assessing which data are in fact useful for these purposes. In the Surveys for 

Electrical Load Prediction section, for example, we performed an analysis of which variables are most 

effective in predicting future electricity consumption. The results of this analysis can be used to 

streamline future surveys used for demand prediction.

It is also often good to have an “I don’t know” response option so respondents don’t feel obligated to 

provide potentially inaccurate information. If no response to a question is applicable, an “other” or “not 

applicable” response ensures that data are complete.

4.2 Survey Implementation

It is important that surveys be administered in a consistent manner. Standardized surveys ensure 

consistency by requiring surveyors to stick to a predefined script. This mechanical approach ensures 

uniform implementation; however, the rigidity precludes enumerators from using their judgment to clarify 

questions and provide guidance to respondents that is off script. Further, developers rightly pointed out 

that surveys are often a company’s first contact with customers and communities. Overly rigid surveys 

may act counter to objectives to build good relationships with communities and future customers. It may 

also make customers uncomfortable to be asked personal questions by outsiders. Ultimately, survey 

implementation must balance the dual objectives of gathering accurate data and building trust and 

goodwill in communities.

Well-trained and experienced survey enumerators are important to ensure that interviews are conducted in 

a consistent manner. Multiple developers expressed concern about forms of interviewer bias, some of 

which can be addressed through proper training. One concern expressed by a developer was that 

interviewers may anticipate answers from respondents and ask questions in a manner that introduces 

acquiescence bias or lead respondents to an answer. This can be addressed by proper training of surveyors 

and is particularly important when using non-standardized surveys. Surveyors must be trained to 

understand the purpose of questions so that they can help respondents understand what is being asked 

while not suggesting or inferring answers. 

Gender- and cultural-based interviewer effects were also raised by study participants. One developer 

pointed out that in conservative communities, males may be uncomfortable being interviewed by females. 

Further, developers noted that some respondents were uncomfortable answering questions from 

enumerators from outside their cultural, ethnic, or racial group, particularly when responding in a 

language in which they may not be completely comfortable. Using surveyors who are from the area or 

familiar with the language, culture, and customs of the target community makes respondents more 

comfortable in their survey experience and avoids miscommunication. This includes respecting local 

gender norms.

For in-person surveys, many developers interviewed implement their surveys using tablet/smartphonebased survey apps. These tools allow survey designers to create interactive custom surveys that permit 

both closed- and open-ended questions and can branch into different subsurveys for different customer 

classes (where, for example, some questions may only apply to a home or to a business). Further, these 
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applications allow data to be collected offline and uploaded to the cloud when connected to the internet. A 

major benefit of using these apps is that it standardizes the formatting of data and automatically compiles 

data into a tabular format. This greatly increases the efficiency of data entry, cleaning, and preparation for 

analysis. Some of the analysis tools developers report using include droidSURVEY and KoBoToolbox.

In-person interviews can be more expensive to implement than via telephone and are often carried out at 

early development stages. Contact information of customers and potential customers is often collected 

during these in-person interviews. Mobile phone numbers allow developers and operators to communicate 

more readily and affordably with customers. Both voice calls and SMS can be used to collect data from 

customers over the phone, though they may have lower response rates than in-person interviews.

Ensuring that surveys, or at least a core number of key questions, remain consistent will allow 

consideration of answers across projects, time, and geographical region. This consistency will allow 

expanded learning that may lead to improved survey techniques and more accurate load assessments, both 

of which will improve the reliability of results, lower project risk, and improve the life cycle costs of 

micro-grid power systems.

4.3 Survey Analysis

Survey analysis methods will vary depending on the type of data being used and the objectives of the 

analysis. However, decisions made during the survey design and implementation phases can make the 

analyses easier. These measures generally hinge on ensuring that the data generated are standardized and 

easy to interpret. 

Creating customer identifications or collecting other data, with which data from different sources can be 

linked to individual customers, will facilitate analysis across data sources. For example, it may be useful 

to analyze customer meter data in conjunction with survey data containing customer characteristics or to 

link customer satisfaction data with payment transaction records. This can be difficult to do after data 

have been collected. This an example of how advanced planning for data collection can help facilitate the 

integration of different databases to extract meaningful data or causal linkages between data, even when 

collected in disparate time frames or repositories.
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5 Conclusions

The use of surveys in micro-grid development is common in Africa; however, the objectives, 

implementation, and scope of surveys varies widely within the sector. This document presents a review of 

current survey practices and lessons learned from a diverse group of eight micro-grid developers currently 

operating in Africa. The document helps to develop a level of standardization in survey practices and data 

collection in the sector, which will lend itself to more consistent predictive analyses based on the 

collected survey data. 

Based on the results of this work, it was found that surveys generally fall into five categories: 

• Market research 

• Site selection 

• Customer applications 

• Customer satisfaction 

• Socioeconomic monitoring and evaluation. 

First, not all developers perform surveys to gather this information, and approaches vary widely from 

informal and unstructured interviews to formal, structured surveys. Both of these approaches have merits 

that are laid out in this document. 

Second, a review of statistical analyses approaches to customer surveys conducted in Tanzania provided a 

view of the uses and potential benefits of using survey data for predictive electrical load purposes in 

micro-grid siting and design applications.

Finally, a further aim of this document has been to develop a set of best practices for micro-grid surveys 

based on insights from developers in Africa with valuable on-the-ground experience as well as established 

survey practices drawn from the literature. These include: 

• Given the breadth of survey work undertaken across the industry, the level of data collection needed 

to meet specific business or national energy access actions should be clearly understood and defined 

early.

• Depending on the type of analysis to be performed, a balance must be struck between structured 

surveys that produce easy-to-analyze and standardized data, and informal interviews that allow 

respondents to express themselves more freely and build trust and relationships.

• Surveys that are developed with a solid understanding of proper survey techniques and potential 

sources of survey bias will yield much more accurate results.

• Use of closed-ended questions will ease analysis of data using computational software. Inclusion of 

response options such as “other,” “not applicable,” or “I don’t know” will help ensure that 

survey data are complete and accurate. 

• Surveys should be developed using current understanding of what information and which questions 

are more likely to provide accurate representations of expected energy usage, such as those provided 

in Figure 2. 

• Because estimation of income from respondents can be difficult to determine and subject to bias, 

proxies of wealth such as household building materials, transportation modes, and expenditures on 

wireless services may be better measures with which to estimate eventual energy usage.
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• To the extent possible, surveys should be conducted using mobile device-based assessment tools 

using clear survey instruments, limiting potential enumerator error, and allowing simplified data 

entry, storage, and analysis.

• To the extent possible, well-trained and experienced survey enumerators who are fluent in the local

language, have experience in energy issues, and understand potential cultural sensitivities should be 

used. 

• Although there is no defined standard and it is expected that survey instruments will change based on 

specific project needs, incorporating a set of standard questions in all surveys to allow comparison 

across projects at installation and early years of operation will be more valuable over time.

Finally, based on analysis of more than 1,000 micro-grid customers in Tanzania and in an effort to 

provide guidance on what kinds of data are useful in predicting demand for electricity among new 

customers. This work proposes a set of survey questions, that can be found in the appendix, that could 

form the basis of a model customer survey.
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29

This report is available at no cost from the National Renewable Energy Laboratory (NREL) at www.nrel.gov/publications.

Appendix

Although it is understood that each survey may be tailored to a specific set of informational needs, the 

following list of questions provides a good overview of questions that should be included. Questions that 

should form a basis for electrical load estimation surveys are bolded, these include both basic 

demographic questions that are necessary for further follow up and system design, as well as questions 

that best support load prediction.

Table A-1. Summary of Customer Application Survey Questions and Response Options

Questions Response Codes

General Information

Household contact Name of respondent 

Connection unique identifier Identifier should include very unique

information that will not be repeated by 

another potential user

Location of respondent connection GPS location of connection

Consumer contact information Respondent phone number or other contact 

information

Connection type Home connection

Home/business connection

Business connection

Other connection

Household Respondent Demographics

Years lived in community Years in community

Household role of respondent Respondent is father

Respondent is mother

Respondent is other

Gender of respondent Respondent is female

Respondent is male

Marital status of respondent Respondent is married

Respondent is single

Respondent marital status is other

Age of respondent Respondent age: 18–30 years

Respondent age: 30–45 years

Respondent age: 45–60 years

Respondent age: other

Education level of respondent Respondent education: some primary

Respondent education: primary

Respondent education: some secondary

Respondent education: secondary
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Table A-1. Summary of Customer Application Survey Questions and Response Options

Respondent education: university

Respondent education: other

Employment status of respondent Respondent employment: employee

Respondent employment: self-employed 

agriculture

Respondent employment: self-employed 

nonagriculture

Respondent employment: other

Occupation of respondent Respondent occupation: business person

Respondent occupation: commercial farmer

Respondent occupation: subsistence farmer

Respondent occupation: teacher

Respondent occupation: other low frequency

Includes: nonfarm laborer, doctor, police, nurse, 

public official, military

Respondent occupation: other

Household Information

Number of people in household (HH) People in HH

Number of people employed in household Number employed in HH

Number of children under 18 in household Children in HH

Number of children attending school in household Children in HH

Average daily hours of study for children Daily study hours

Number of infants in household Infants in HH

Number of rooms in home Rooms in home

Number of sleeping rooms in home Bedrooms in home

Normal bedtime Bedtime: 9 p.m.

Bedtime: 10 p.m.

Bedtime: 11 p.m.

Bedtime: Other

Normal wake time Wake time: 5 a.m.

Wake time: 6 a.m.

Wake time: Other

Annual household income Income: 0–500,000 TSH

Income: 500,000–1 million TSH

Income: 1 million–3 million TSH

Income: 3 million+ TSH

Does income fluctuate seasonally? Seasonal income fluctuation: no
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Table A-1. Summary of Customer Application Survey Questions and Response Options

Seasonal income fluctuation: yes

Business Information

Nature of business Business type: bar

Business type: guest house/hotel

Business type: shop

Business type: phone charging

Business type: restaurant

Business type: other low frequency

Includes: agrovet, butcher, chemist/pharmacy, 

church, mosque, clinic/dispensary, 

kinyozi/salon, milling, office, school, video 

hall, other

Business type: other

Building Characteristics

Construction material of building Building type: brick

Building type: old/crumbling concrete

Building type: well-built concrete

Building type: wood

Building type: other

Ownership status of building Building ownership: own

Building ownership: renting

Building ownership: other

Energy Sources and Uses

Electrical appliances owned before micro-grid Pre micro-grid appliances: none

Pre micro-grid appliances: CD/DVD player

Pre micro-grid appliances: high watt TV

Pre micro-grid appliances: light bulb

Pre micro-grid appliances: low watt TV

Pre micro-grid appliances: phone charger

Pre micro-grid appliances: radio

Pre micro-grid appliances: sound system

Pre micro-grid appliances: other low 

frequency

Includes: satellite TV receiver, printer/copier, 

computer, shaver/clippers, microwave, 

refrigerator, other

Pre micro-grid appliances: other

Appliance planned to be acquired Planned appliances: CD/DVD player
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Table A-1. Summary of Customer Application Survey Questions and Response Options

Planned appliances: computer

Planned appliances: electric iron

Planned appliances: light bulb

Planned appliances: low watt TV

Planned appliances: phone charger

Planned appliances: radio

Planned appliances: refrigerator

Planned appliances: sound system

Planned appliances: other low frequency

Planned appliances: other

Includes: none, high watt TV, printer/copier, 

shaver, hair clippers, microwave, hair dryer, other

Is firewood used as an energy source? Energy source: firewood

If yes, how is it used? Firewood use: cooking

Firewood use: heat

Firewood use: other

Is a solar home system (SHS) used as an energy source? Energy source: SHS

If yes, how is it used? SHS use: electricity

SHS use: lighting

SHS use: phone charging

SHS use: radio

SHS use: television

SHS use: other

Are propane, diesel, petrol, kerosene, or batteries used 

as an energy source?

Energy source: other low frequency

Includes: propane, diesel, petrol, kerosene, 

batteries

If yes, how are they used? Propane use: cooking

Gasoline use: cooking

Gasoline use: electricity gen.

Battery use: electricity

Battery use: lighting

Battery use: television

Battery use: phone charging

Battery use: radio

Battery use: other

Diesel use: electricity gen.

Diesel use: heat

Diesel use: lighting
33

This report is available at no cost from the National Renewable Energy Laboratory (NREL) at www.nrel.gov/publications.

Table A-1. Summary of Customer Application Survey Questions and Response Options

Diesel use: other

Kerosene use: lighting

Kerosene use: other

Are other energy sources used? Energy source: other

If yes, how are they used? Other source: cooking

Other source: lighting

Other source: phone charging

Other source: radio

Other source: television

Other source: other low frequency

Includes: electricity, heat, fan

Other source: other

What source of energy is used for cooking? Cooking source: firewood

Cooking source: other

What modes of transportation are owned/used? Transport: bicycle

Transport: car

Transport: motorcycle

Transport: boat

Transport: other low frequency

Includes: animal cart, truck

Transport: other
usaid.gov/powerafrica | nrel.gov/usaid-partnership

Katrina Pielli

Senior Energy Advisor; Lead, Beyond the Grid

USAID | Power Africa

Tel: +27 12-452-2086 

Email: kpielli@usaid.gov

Samuel Booth

Senior Project Leader, Micro-Grids

National Renewable Energy Laboratory (NREL)

Tel: +1-303-275-4625 

Email: samuel.booth@nrel.gov

NREL/TP-7A40-72339 | May 2019

The Power Africa, USAID, and NREL Partnership addresses critical 

challenges to scaling up the implementation and investment in micro-grids 

for energy access through technical support partnerships and application 

of NREL’s Quality Assurance Framework.