Africa: As Solar Refrigerator Keeps Mangoes Cold, Farmers’ Profits Heat Up


Solar-powered cold storage and biological pest control are helping protect Kenya’s mangoes from climate change.

It is a hot and cloudless morning, a sign that it will be sunny right through the afternoon. Joseph Mailu moves along rows of fruiting mango trees with a long pole in his hand, harvesting the mature fruits.

The succulent green mangoes drop inside a net tied to the tip of the pole which prevents them from falling on the ground and being damaged.

The quality of the fruit is a big concern to farmers and traders hoping to sell to the lucrative export market.

But now farmers in Nziu are benefitting from two innovations – solar-powered cold storage, and biological pest control – to help protect their harvest against the effects of climate change.

Even with the careful skills of professional harvesters like 31-year-old Mailu, efforts to access high-end markets used to be difficult for many farmers in Nziu, a village in Makueni Country, some 250 km (150 miles) from Kenya’s capital, Nairobi.

But the new cold storage facility, which preserves the farmers’ highly perishable fruit and stops it from going rotten before it reaches consumers’ tables, is making things easier.

The state Department of Agriculture estimates that 30-50 percent of harvested fruit in Kenya goes to waste due to poor post-harvest handling.

The majority of Kenya’s smallholder farmers lack proper cold storage to preserve the quality or extend the shelf-life of their fruit, leaving them at the mercy of middlemen who buy their produce and earn most of the profit.

With low-cost cold storage, however, about 150 of Nziu’s farmers now can keep their harvest refrigerated while they scout for prospective buyers.

The refrigerator, the first of its kind in Kenya, was built in late 2015 by the Rockefeller Foundation and TechnoServe, a nongovernmental organisation, under the YieldWise programme, an initiative aimed at cutting post-harvest losses among local mango farmers.

The facility is fitted with four solar panels, an inverter and a car battery which enables it to store power to keep running during the night hours.

Makueni County is semi-arid and hot, especially during the mango harvesting season in January and February, but the cold storage room can reduce the ambient temperature from 35 degrees Celsius to as low as 17 degrees, which slows the ripening of the mangoes by several days.

John Musomba, a farmer in charge of the refrigerated storehouse, said it can store up to 3.4 tonnes of mangoes.