Nigeria loses 30–50 percent of its domestic fish to spoilage from poor processing, and the National Institute of Freshwater Fisheries introduced a new method to fishermen around Kainji Lake. The solar energy tent fish dryer is a simple but effective method of dehydrating, smoking and drying fish to increase its shelf life. The method can dry one ton of fish in 18 hours.
The technique is simple: place black stones on the ground, a rack on top, the fish on the rack, and a polythene bag over all to create a mini-greenhouse effect. Preserving fish is only one of the benefits; the other is preventing deforestation from the wood-fueled smokers traditionally used to preserve fish. In developing countries, wood fuels 80 percent of the domestic energy needs of the population. Several fish-drying units have been developed by processors in the Kainji Lake basin.