Back in 2014 Energy Futures Lab funded then-PhD student Davide Moia to go to Rwanda. Davide, working on alternative materials for solar cells, joined his colleague Chris Emmott in a Climate-KIC funded project to test plastic solar panels in rural Rwanda. They applied for funding from the Energy Futures CDT and in August 2014 they found themselves a long way from home. Davide has delved into his memories and written us an amazing blog post about the journey and a followup trip in 2015.

“Amakuru?”. This is what you should ask people in Rwanda before starting a conversation. “How are you?”. It is important, first of all, to make sure that the person whom you are talking to is “ni meza”, that he or she is well.

This is what Longin, one of the translators, told me while sitting in the back of a jeep during my first trip to the rural areas of Rwanda. Now, back in London, I can barely read “Amakuru” and other expressions that I wrote in my notebook on that day, while driving on those bumpy roads. What was I doing there?

Back in 2014, myself and colleague Chris Emmott were working towards our PhDs, investigating the potential of making solar panels with plastics and other organic materials, as a competitive source of renewable energy and a way to mitigate climate change. On a sunny evening in July that year, Chris and I met for a beer next to Hyde park. He suggested I join him for an ambitious and exciting project: installing organic photovoltaics (OPV) in Rwanda to monitor their performance in the harsh conditions faced in rural areas of Africa. As an experimentalist working in this field, I often think that the development of new types of solar cells needs more “real world” testing. Stability of the organic materials that we use in the lab is often the bottleneck for upscaling and commercialisation of the technology.

So, a month later, I was in the back of a Jeep, trundling through the dirt tracks of Rwanda’s southern plains. Along with myself, Longin and Chris, there was Phillip Wood. Phil was Climate-KIC’s media assistant who joined our team and helped us on the ground to report on the project and sort out many of the problems we encountered during the trip. You can still read Phil’s blogs from the time for details.

After a couple of hours driving, we arrived in Kagano, a small village in the eastern province of Rwanda. Stepping out of the Jeep, we were quickly surrounded by dozens of kids, laughing and shouting “Muzungu” (“white man” in Kinyarwanda). The experience was as amazing as I had always imagined, but this time it was real. Their emotions were so intense. When we spoke english, which they learn at school, when we tried to speak Kinyiarwanda, when we put on suncream, which probably left them wondering “is that how you guys became white?” That day certainly was a special one for them too.

A few people did seem to carry on living their lives after our arrival. Some of them working in the fields, women washing clothes in a common reservoir, men grilling bruschettes and bananas, some attended a small shop or bartered at a small market, others enjoyed homemade banana beer, many had been enjoying this since early that morning. But around 6 pm the sun sets, and it does so for everybody. It is hard to imagine experiencing deeper darkness than that. This does not stop most people from doing things in the village. We watched some cycle out of the village into complete darkness, with no lights, unable to see the bumps in the rutted road. To our eyes, life in Kagano is not easy. After 6pm it’s practically impossible.

Lukas Lukoschek, the CEO of Meshpower Ltd, had also joined us. At the time his company was a young startup  based in the incubator of Imperial College London. Lukas and his team had already been installing minigrids for a few years at this point. These solar powered grids give electricity to small villages providing customers with light and a mobile phone charger.

Our collaborations with Meshpower, in particular with Lukas and his colleague Charith Amarasinghe, and with Prof. Frederik Krebs from the Technical University of Denmark (DTU), had made our project possible. Meshpower generously allowed us to connect our measurement system to the distribution board that they control remotely from London. This enables remote monitoring of the solar panels we installed. Prof. Kebs’ group fabricated and provided us with state of the art OPV modules. These are printed on plastic foil and laminated to form a thin semitransparent plastic sheet.

During our stay in Rwanda, Chris and I installed 25 OPVs on the roofs of four houses within three different villages. As part of the experiment, we applied them to the rusty roofs of these villages using only velcro and duct tape, to see if such low cost solar and mounting materials could really last under the intense heat of those rooves.

The data that we collected showed that OPVs were able to convert solar energy into electricity for about four months before starting to show signs of significant degradation. Our study brought further insights into the current potential of OPV as a technology for off-grid solar systems and also shed light onto practical factors that are critical to the lifetime of these devices and should be considered for future scientific research.

In 2015 Chris and his colleague Phil Sandwell made a second trip to Rwanda. They replaced the panels that ceased to work and took them back to London for further analysis. The ease of installation and potential low cost of OPV could make a difference for people living in the rural areas of the world. For this to happen, printed photovoltaics has to prove to be a reliable and cost effective option. Our trip was not just an amazing experience but an important test for the technnology we are working on here at Imperial: a real world experiment.

The study was published last year in the journal Solar Energy Materials and Solar Cells as In-situ, long-term operational stability of organic photovoltaics for off-grid applications in Africa.