Solar panels are not a new way to provide cheap power across much of the African continent, where there is rarely a lack of sunlight. Growing crops beneath the panels, on the other hand, is feasible, and the process has shown such promise in Kenya that it will be implemented this week in open-field farms.
Agrivoltaics Technique
The technique, known as agrivoltaics, harvests solar energy twice: panels are traditionally used to harness the sun's rays to generate energy, but they are also used to provide shade for growing crops, aiding in the retention of moisture in the soil and boosting growth.
An initial year-long research collaboration between the University of Sheffield, World Agroforestry, and Kajiado-based Latia Agripreneurship Institute has yielded promising results in the semi-arid Kajiado county, a 90-minute drive from Nairobi, and the full project will be officially launched this week.
Cabbages grown under the 180, 345-watt solar panels, for example, were a third larger and healthier than those grown in control plots with the same amount of fertilizer and water. Other crops, such as aubergine and lettuce, have yielded comparable results. According to Judy Wairimu, an agronomist at the institute, maize grown under the panels was taller and healthier.
"We wanted to see how crops would perform under these panels," Wairimu explained. But there's another practical reason for the technology, she says: doubling the output of the same patch of land to generate power and cultivate food can go a long way toward helping people with limited land resources.
The trial initiative, according to Dr. Richard Randle-Boggis, a researcher at the University of Sheffield's Harvesting the Sun Twice project, will determine the potential of agrivoltaic systems in east Africa.
"We needed to build a test system to see if this technology will be suitable for the region," Randle-Boggis said, emphasizing that, unlike traditional solar mini-grid systems, agrivoltaics have the added benefits of improving food and water security, strengthening people's resilience to the climate crisis, and providing low-carbon electricity.
The solar panels not only reduce water loss from plants and soil, but their shade also alleviates some of the stress experienced by plants as a result of high day temperatures and UV damage, according to Randle-Boggis.
Increasing Farmer’s Income
Agrivoltaics can have a significant impact on household income in remote areas like Kajiado. "Women here can spend up to 300 Kenyan shillings (£2) on a bodaboda (motorcycle taxi) fare to the market just to buy vegetables worth 100 Kenyan shillings," said Anne Macharia, training director at Latia Agrepreneurship Institute.
The solar panels can be installed three metres above the ground, allowing enough space for a farmer to work below, or higher in larger systems to allow access for agricultural machinery.
Randle-Boggis acknowledges the technology's limitations, but believes that in "areas of Kenya that are not currently suitable for horticulture, it may be possible to grow other crops under the improved environmental conditions provided by the panels." The technology has been used successfully in other countries such as France, the United States, and Germany.
