Photo credit: Kat Harrison

Encouraging children to do their homework can be a tough task at the best of times. But imagine if you were asking your daughter to sit by a dim, polluting, kerosene lamp to do her maths; or having to encourage your son to strain his eyes in order to read his bedtime story. For many families across the developing world, this is part of normal life.

In this Series, we’ve shared updates from cutting edge research on the impact on households of solar energy, in particular solar lanterns. We’ve found that switching to solar dramatically reduces indoor air pollution, that price doesn’t affect adoption, and that the extent of impact across multiple dimensions is dependent on context. And amongst all the attention solar has been given, one theme has perhaps grabbed most attention of all, the expected benefits of improved electrification for study.

Indeed, many solar entrepreneurs have zeroed in on the benefits of solar for study in their advertising. SolarAid (where I used to work), a UK-based charity operating in Africa, take it a step further. Their last mile distribution model works alongside the Ministry of Education in Malawi, Uganda, and Zambia, to sell and raise awareness of solar lights through School Campaigns. The benefits of solar for study seem intuitive enough but what do we really know about them; is solar a potential contributor for developing county’s education deficit?

Using our Lean Data approach we’re beginning to learn a lot more about this important topic. For instance, there is a growing amount of data to suggest that children living in homes with solar lights, are consistently studying for longer; up to an hour more each day.[1] So far so good, for the case linking solar to education.

What has remained more puzzling is whether this extra study was actually leading to improved educational outcomes. To try to answer that trickier question, we required more in-depth research. So, in partnership with SolarAid and Stanford University, we embarked on a study to learn more about the effects of access to light for schoolchildren’s schooling.

Our research worked with over 1,400 students in grades 7 to 9, attending 12 government primary schools in the Zimba district of Zambia — a place where three-quarters of the population are not connected to grid electricity and therefore we might expect the benefits of solar to be largest.

What did this research show? Providing solar lights didn’t result in improved educational attainment or changes in study habits for children. In fact, the type of light children used for doing their homework didn’t correlate to examination results. However, it’s important to be aware of the context and note there are a number of factors to consider when looking at these results.

Photo credit: Kat Harrison

Here’s more:

There are other important elements, as well as light, that impact educational outcomes. For example, only 10% of the children in the study said that not being able to study in the dark was the reason why they didn’t complete a homework assignment before the solar lights. Instead, sickness and children being overwhelmed with too many other responsibilities (like work or chores) beside school were the main reasons given. Basic hurdles to educational achievement that relate to poverty (like expensive school fees and lack of school supplies) are a more important factor than solar lights as a key educational input.

There was low adoption of the solar lanterns. While this isn’t good news, it may give context for the results. Very few of the children used the solar lights they were given. And we’re not sure why. This may have been because of reported problems with the on/off switches of the lights, it may have been because more powerful members of the family used the solar lanterns instead of the children, or it could be that children didn’t see the benefit of switching from flash-lights to solar lanterns. This finding doesn’t reflect the results of most other research in this area,[2] so there’s more digging for us to do to fully understand what happened.

Solar may be replacing flashlights rather than lanterns in Zambia, muting the potential benefits. In Zambia, the main source of lighting for off-grid families is torches or flash-lights, and in this study, 72% of families were using a flash-light as their main source of light. In general, a torch may not provide significantly different quality of light to solar lanterns in terms of brightness. The research did not answer this, but it is possible that we may see more educational-related impacts in countries or areas where kerosene lamps are the main source of off-grid lighting for families, like in Kenya, Tanzania, and Uganda.

So, the results may not be as positive as we might have hoped, but what lessons can we learn from it? Well, this study showed that not many children used the solar lights for studying. There may be a research effect here and further research in this area may be useful, for example, to consider the role and impact of social marketing. For solar lights to have more impact on educational outcomes — and this includes motivation and attendance — it is likely that marketing and demonstrations need to be more explicit to encourage, promote, and showcase this. There is also an opportunity for us to do better at responding to customer usage issues. There were quite a few reported issues with the solar lights which may have affected uptake. Warranties are not claimed and are often tricky to uphold — this is a key outcome of both this study and others: to enable meaningful uptake, we need to get better at after-sales support.

The lesson here, then, is not that solar lanterns are not having impact, but rather their impact may be more significant and direct in other areas. And potentially also in certain environments — like countries where kerosene lamps are used more. So, again, context matters. This Energy Impact Series showcases many of these other areas of impact. These include savings on energy spending for poorer families, reductions in exposure to indoor air pollution particularly for children, and improved safety and well-being captured through our Lean Data work.

If you’d like to read more about the results of this research, you can find the full academic working paper here.

[1] SolarAid data (2012–2015), Harsdorff et al. (2009), Powering Education (2014).

[2] Rom et al. (2016), SolarAid (2012–15), Acumen Lean Data (2016–18), and more.


This is the ninth installment of a series of lessons from a range of new research into the social impact of off-grid energy in emerging markets. The research is complemented by Acumen’s own customer-based data collection applying our Lean Data approach. This work was originally conceived by Kat Harrison, formerly head of research and impact at SolarAid and now Acumen’s Associate Director of Impact & Lean Data.