When dawn breaks over Kanyawa village in Gilgil, Nakuru County, Kenya, smallholder farmers step into fields planted to indigenous vegetables such as managu and terere. For many growers, the main challenge has been managing produce after harvest. Middlemen often delayed payment or did not pay at all, and during periods of oversupply, vegetables were lost before reaching markets.
Post-harvest losses remain widespread among smallholders across Africa. A 2025 study protocol in Frontiers reports that Sub-Saharan Africa loses up to 50 per cent of fruits and vegetables annually. In Kenya, more than 70 per cent of smallholders lack access to cold storage, according to the World Bank. The Kenya Ministry of Agriculture estimates that the country loses food worth about US$942 million per year due to post-harvest losses, a figure influenced by climate variability.
Farmers, cooperatives, and agribusinesses in East Africa are adopting solar-powered technologies as temperatures rise, grid power remains unreliable, and demand grows for lower-cost preservation options. Solar drying has become a widely used method for vegetables, extending shelf life without electricity.
Nyakazi Organics, a youth and women-led enterprise, uses a locally made solar dryer to process indigenous vegetables and fruits. "We use a locally made solar dryer powered entirely by sunlight to dry indigenous vegetables and fruits," says Mercy Manyange, the co-founder and operations lead. Farmers contracted by Nyakazi supply vegetables for drying, and the technology has provided more predictable marketing options.
The solar dryer uses trapped heat to dry vegetables in two to three days, compared to a week under traditional sun drying. It keeps produce protected from dust, insects, and contamination and yields a product with a shelf life of up to one year. "We chose to use a solar dryer because it is energy-efficient, unlike electric dryers that are expensive and often inaccessible to smallholder farmers in rural areas," adds Manyange.
Since 2023, Nyakazi has processed more than 20 tons of vegetables sourced from over 200 smallholders, most of them women. A survey by Seed Savers Network indicates that growers supplying Nyakazi increased their average monthly income from vegetables by 30 to 50 per cent and reduced time spent in markets by up to 80 per cent. "Before, I would spend the whole day at the market trying to sell my vegetables," says farmer Beatrice Ndungu.
Similar adoption trends are reported across Uganda, Tanzania, and Rwanda, where solar drying, cold rooms, and solar irrigation are expanding through government and donor-supported programs.
Nyakazi faces constraints, including slow drying during rainy periods, limited dryer capacity, and certification and financing barriers. The enterprise plans to expand solar drying hubs into more counties, develop new dried products, and explore export channels.
"This technology is simple, but the impact is powerful," Mercy says. "It protects food, protects farmers, and strengthens resilience."
Source: ScienceAfrica
