Impacts of PicoPV and Consumer Research

From energypedia

►Back to Solar Portal


As experience with other renewable technologies show, lack of social acceptance and incongruity with cultural values and norms are common barriers during the implementation phase. Therefore, it is important to investigate in users needs and behavior patterns. Additionally, experience shows that laboratory test have to be complemented with field tests in order to test the solar lanterns under real-life conditions. Due to the fact that many bad quality products exists, it is also important to test selected products in a field test.

GIZ Energising Development has conducted various tests in different countries, such as Bangladesh, Bolivia, Ethiopia, Mozambique, Nicaragua, Peru, Senegal and Uganda. Approaches of these tests differ, results and outlook are presented within this articles.

Performance of Solar Lamps

More than 100 firms are offering PicoPV products in developing countries today, but most products are of very low quality, with serious implications for consumer trust in the new technology. Early lab tests have focused the awareness of governments and donors on the importance of quality control and customer information – however, field tests in sufficient countries with sufficient sample sizes are needed for a better understanding of PicoPV performance under real-life conditions, and to identify gaps in the emerging draft lab test procedures. Field tests show, that lab testing does need to be complemented through long-term testing under real-life conditions.

Occurrence rate of technical problems (10% to 50%) during a field test in Uganda confirm this statement. Furthermore, the Uganda data highlight the urgent need to introduce quality labeling mechanisms, based on proven test procedures, on international as well as local levels: Almost all lamp models, including top-end products with high quality claims by manufacturers, did not meet expectations in terms of durability and robustness – in spite of the fact that they had been picked as “best of class” in the previous lab test (which in turn was based on the lab test draft methodology currently in use by Solar Laterns Test as well as Lighting Africa Outstanding Products). Particular technical improvements concluded from the Ugandan field tests are: manufacturers need to improve products’ solar fraction, equip lamps only with advanced charge controllers, and work on the robustness of the products, and of the connection parts in particular. Problems were: frequent deep-discharge of batteries, low battery life-spans and overall unsatisfactory lighting service were the frequently observed. Apart from that, the components that most often caused lamps to fail were cables, plugs, input jacks and switches. These parts are obviously under extreme stress when lamps are in everyday use by extended families with several children, and when modules are put down for charging on the ground in the courtyard (while lamps are kept inside to protect them against thieves). [1]

In Ethiopia, broken switches and deeply discharged batteries were a frequent problem. Robustness has to be improved as well, because users often carry their systems around due to fear of theft.

►Go to Top

General Experiences Field Tests

The GIZ PicoPV country survey results underpin that an ‘one-size-fits-all’ lamp model does not exist. The lamp models were rated differently by users across different continents, and they were liked and disliked for different reasons. However, there are some aspects that turned out to be important for consumers in all the test countries.

►Go to Top

Aspect's Customers

Above all, light quality, including the size of the light cone and light intensity, mattered most to the majority of respondents. Apart from that, in Latin America it was the radio function that made people like certain lanterns, whereas for African consumers the phone charging function was considered more important. Another selling point for lamps in Uganda was visual resemblance of the kerosene lanterns that are conventionally used there. For these reasons, people felt that the solar lamp could directly replace the traditional model and therefore perceived it as particularly useful and relevant.

Another result that emerged from the research was that consumers are highly suspicious of poor quality products that have only a short lifetime. Even among poor households there is a willingness to pay for quality, and there is evidence that the target consumer groups do think ahead and are not interested in products that may be relatively cheap but have to be replaced after a short time. There is also concern among all potential retailers that maintenance and repair services may be a major hurdle towards the development of PicoPV markets in rural areas, where there is no local expertise on these new kinds of products.

The field survey also revealed certain reservations by different consumer groups against some visual design features that will have to be taken into account for any successful PicoPV marketing strategy. For example, people had very particular positive or negative associations with certain colors or forms which might have an impact on their purchasing decision even though they said that these product features were not decisive factors. One lantern, for example, reminded Ugandan women of a camera, which limited its attractiveness, while in Nicaragua people particularly liked the handy format of the lamp.

Initial Auction Price

Purchasing Price

Aishwarya with radio radio 73
Aishwarya without radio 62, 5 34
Solux LED 100 151 75, 5
Freilassing +radio 177 88, 5
Solux LED 50 50
not sold
Solata 23 23 not sold

In Mozambique, one of the lamp models was described as “masculine” so that women would hesitate to use it. In Uganda, white is associated with religious ceremonies like funerals and therefore not regarded an appropriate color for a lamp.

In Ethiopia, a large angle of radiation was preferred over a high number of lumens. Portable lamps were favored. Users preferred a built-in switch instead of a pull switch. Furthermore, bright, white light was clearly chosen over yellow colored light. Regulators in order to adjust the level of brightness are an additional feature people liked. Importance of mentioned characteristics, such as light quality and good quality of the system itself can be confirmed. Moreover, duration of light and robustness played an important role in the decision to buy a PicoPV system

In general, it can be noted that overall the tested PicoPV lamps proved robust and performed well during the field trial.Here again, an interesting observation is that the performance of the same lamp models was not the same across all countries due to the specific local conditions.

►Go to Top

Willingness to Pay (WTP)

The willingness to pay (WTP) for PicoPV products in general, and for certain lamp models in particular, differed enormously between the countries. African users indicated a higher willingness to pay than users in Bolivia and Nicaragua (again, leaving much room for future validation of applied methods and ways to account for potential behavioural differences between survey countries). The figures obtained through Dutch auctions indicate a WTP of 50-90 USD for lamps of the highest value class from a consumers’ perspective. Lanterns falling into a medium value category were bought at 25- 50 USD. The remaining lanterns were sold for 5-25 USD. In spite of these high willingness to pay indications, a central finding from all the country surveys was that many households at the bottom of the income pyramid, which are in fact the main target population for PicoPV lamps, often lack the required cash availability. Even though the purchase of a lamp would pay off within a few months due to savings on running costs of conventional lighting solutions, consumers, notably in rural areas, mostly do not have the cash available to pay the upfront investment and have no access to financial services which could support by-passing this problem. This is a major a hurdle for the large-scale distribution of PicoPV lamps in LDCs. This is particularly true for the more expensive PicoPV lamp models, which range between 80 and 150 US$ per piece.

A consumer credit scheme piloted in Uganda suggests that offering the possibility of payment in rates enhances affordability of the lamps by rural households tremendously. The willingness to pay (WTP) figures collected in the GIZ PicoPV field survey by far exceed the respective figures resulting from household surveys under the Lighting Africa Market Research programme. This high deviation may be partly due to the very different research approach used by Lighting Africa in this part of the survey, where households were asked to indicate their WTP statements for different lamp types without having had a chance to test-use them.

Table shows how much people spend monthly for traditional lighting devices and how much they are therefore able to pay. Furthermore, degree of substitution of conventional lighting is presented.[2]




Ethiopia 4.2
Ghana 5.6 1.4 2.3
Kenya 10.9 0.8 1.4
Tanzania 7.5 1.5 2.3
Zambia 8.2 4.7 2.3

degree to wich conventional lighting is substituted by solar lamps
monthly expenses (running costs) for conventional lighting devices monthly duration of use of conventional lighting devices
Bolivia 66% of test users completely abandoned the use of candles;
59% reduced or completely abandoned the use of kerosene lamps;
90% reduced or completely abandoned the use of batteries.
candles – US$ 2.3
kerosene – US$ 3.2
batteries – US$ 5.9
total (hh average)13 – US$ 9
hours of use of traditional lighting devices
per month14:
110 -120
Nicaragua 93% of test users substituted traditional lighting devices (candles,
kerosene lanterns) by 100%.
candles - US$ 3.7
US$ 4.8
batteries for torches (linternas) – US$ 3.2
batteries for lamps
(lamperas) – US$ 1.6
duration of use / month
candles – 61h
kerosene lamps – 92h
battery torches (linternas) – 61 h
battery lamps (lámparas) – 70h
Uganda (NACWOLA test users)
90% of test users completely replaced their formerly used lamps. candles – US$ 4.7
kerosene – US$ 8.2
batteries for lanterns – US$3.7
candles – 57h
kerosene lamps with glass cover – 114h
kerosene lamps with single wick – 214h
light bulb in socket – 102h
battery lanterns – 94h
battery torch – 62h

As part of the baseline analysis of the GIZ field surveys, households were asked to specify their monthly expenditures for conventional lighting devices, whereas the ex-pot survey assessed to which degree the PicoPV lamps had replaced the use of these traditional lighting devices. The finding across countries was that PicoPV lamps have a true potential to substitute conventional lighting sources to a large degree. The associated substantial savings (and poverty alleviation)potential through the use of PicoPV lamps is underpinned by both the GIZ field survey data on lighting costs and the respective Lighting Africa Market Research results from the large-scale household survey in part II of the research project (n=1000 for each country).

►Go to Top

Specific Country Experiences

Besides the studies mentioned above, market research on PicoPV systems is limited and has so far focused on lighting appliances such as solar lanterns. As rural customers expect more than only light but also other energy services as mobile phone charging or radio, existing studies could be seen as somewhat one-sided.

►Go to Top

Kenya (ITC)

In a study conducted by ITC in Kenya in 1998 people in urban and rural areas were asked for what purpose they would use solar lanterns:

The main priority was given to (1) ambient lighting in households. This was followed by the desire for (2) studying and reading, using the light to (3) conducting housework during the dark hours and improving the (4)perceived security by having bright light in or in front of their houses. The least importance was given to (5) business. If only rural areas had been taken into account security would have had the lowest ranking[3].

The ITC survey was the first step to discover what customers would expect from their solar lantern. Out of these findings the “Glowstar”-lantern was developed.

Ranking of preferred features of solar lanterns, Kenya (ITC, 1998)

Service characteristics:

  • The maximum price of the lantern should be no more than $75
  • The lantern should provide light for up to 4 hours each evening
  • Customers should have access to affordable an readily available spares
  • Customers expect an overall lifetime of the latern of 6 years
  • Customers expect a 12 months warranty for the product.

Design characteristics:

  • The lantern should spread the light over 360°.
  • The bulb enclosure should allow maximum transmission of light.
  • The carry handle should be sturdy and comfortable.
  • The preferred choice of bulb is a 5W CFL.
  • The lamp should be portable and weigh no more than 2.5 kg.
  • The lantern should be stable with a good base.

Some of the extra features that potential customers expressed a need for were:

  • An indicator to show that lamp is charging,
  • A warning light to show that the lamp is about to switch off when the battery is low,
  • A power socket to allow a small radio to be connected to the unit.

►Go to Top

India (Stanford University)

A survey (Stanford University 2003) which summarises experience from various states of India indicates that the rural population uses kerosene to a large extent for lighting of approximately 2-4 hours per day. Given that 60% of India’s population live in rural areas, there is a vast market potential for PicoPV, which can cut household energy expenses by replacing fuel-based lighting. The survey also found indication of demand for PicoPV among those parts of the Indian population which have access to the grid, as power supply in most rural areas is highly unreliable.PicoPV may serve as a back-up during power outages for this consumer group which is marked by higher income levels and has a demand for higher quality energy services.

The survey also brought to light that most target customers would not be willing to pay 100% up front in cash for purchasing a system. However, these results vary extremely between various regions. Some of the interviewed groups would prefer some form of microfinance option through retailer financing, village co-operatives or saving groups.

►Go to Top

Tanzania (GIZ)

From GIZ experiences in Tanzania, it has been observed that customers prefer to have a switch installed in the house rather than a portable system. Even if it provides only very basic services, there was a preference for small solar home systems at least if they are affordable. Furthermore, a disadvantage of portable systems has been that they can be stolen easily in comparison to a fixed system in the house. A crucial point has also been the recharging of solar lanterns. As they are usually placed outside and oriented to the sun in the morning and remain in the same position throughout the day, the full charging potential cannot be achieved.

Installment Size  % Surveyed Expressing Preference
Rs. 100 or less 29-31%
Rs. 150 14-22%
Rs. 200 34-37%

Worldbank's Lighting Africa has accomplished as well a field test with PicoPV systems. A summary of their report is given in this article.

►Go to Top

Ethiopia (GIZ)

In a quantitative study in Ethiopia in 2010, users report improvements in education, health and economics after a field test of three months. Thus, these findings are in line with benefits contributing to the MDGs, presented in the EnDev Report on Impacts. Furthermore, benefits in social community were reported by users: socializing and visits in neighbor's houses were enhanced due to an improvement of security outside (e.g. avoidance of injuries by thorns or dangerous animals). Since solar lamps could be used simultaneously by various people, less conflicts arose about the usage. Furthermore, parents start having discussions and sharing ideas with their children. Thus, relationships between family members improved. Parents are reassured, because their children can use the solar lamps without fear of accidents (e.g. fire). Particularly women are relieved from their worries about energy supply (planning, management and procurement of light sources as well as a fear of emergencies without light).

►Go to Top

Rwanda (RENEW IS-Academy)

In 2011, there was carried out a field study of four Philips Lighting products in rural households in Rwanda. The specific focus of the study by Selen Kesrelioglu is to examine whether the lighting products may provide educational benefit to a target group comprising rural teacher and student households.

The study was performed in the context of the RENEW IS-Academy, a Dutch research collaboration investigating energy access and development cooperation in Eastern Africa. The main project partners include the Institute for Environmental Studies (IVM), the Energy Research Centre of the Netherlands (ECN), and the Dutch Ministry of Foreign Affairs (DGIS).

The proposed research question “How do Solar Portable Lighting (SPL) products affect the amount of time spent on educational activities in Rwanda?” examines the impacts of SPL products on educational activities undertaken by teacher and student households in rural Rwanda.

The primary indicators for the research question are;

  • Time spent on educational activities with the introduction of the SPL light source as compared to the baseline study

- Days a week spent on educational activities at home
- Hours a day spent on educational activities at home

  • Social attitudes and values

- Household attitudes toward education

- Attendance levels at schools by students

- Resources and physical environment available for households to conduct educational activities
- Do households have access to educational materials to study with?

  • Economic

- Baseline kerosene and candlelight expenditure
- Avoided cost of kerosene and candlelight with the introduction of the SPL
- Willingness to pay and payback period of the SPL

In each sector, 6 student households and 12 teacher households participated. Student households are defined as pupils in the participating districts and teacher households are defined as teachers that are members of the Teacher’s SACCO. Headmasters of participating schools selected the student households. The key informants of the study are teacher and student households that are users of kerosene fuel or candlelight for lighting. Interviewed households had no access to electricity.

There exists some variation on the results depending on the type of household (teacher or student) and the product provided to the household. Notwithstanding, the data identifies an overall increase in time spent on educational activities per week for students. Outcomes for teacher households, however, depend on the type of product that was introduced. However, since existing lighting practices focus on educational activities, it is important to look at the perspective on the quality of the light as well. Lastly, the study identifies the Solar Home Systems (SHS) was preferred and provided the most advantageous lighting service in terms of time spent on education, as well as providing additional benefits such as cell phone charging. The SPL products provided a large added income benefit, as there was a substantial decrease in the monthly expenditure on lighting by households after the introduction of the SPL.

►Go to Top

Further Information

►Go to Top


  1. GTZ, iidevelopment. 2010. GTZ Solar Lamps Field Test Uganda - Final Report.
  2. GIZ. 2010. What difference can a PicoPV system make? Early findings on small Photovoltaic systems - an emerging low- cost energy technology for developing countries: GIZ PicoPV Booklet
  3. ITC, 1998