ScienceDaily (Jan. 5, 2010) — Solar-powered drip irrigation systems significantly enhance household incomes and nutritional intake of villagers in arid sub-Saharan Africa, according to a new Stanford University study published in the Proceedings of the National Academy of Sciences (PNAS). The two-year study found that solar-powered pumps installed in remote villages in the West African nation of Benin were a cost-effective way of delivering much-needed irrigation water, particularly during the long dry season.
"Significant fractions of sub-Saharan Africa's population are considered food insecure," wrote lead author Jennifer Burney, a postdoctoral scholar with the Program on Food Security and the Environment and the Department of Environmental Earth System Science at Stanford. "Across the region, these food-insecure populations are predominantly rural, they frequently survive on less than $1 per person per day, and whereas most are engaged in agricultural production as their main livelihood, they still spend 50 to 80 percent of their income on food, and are often net consumers of food."
Burney and her co-authors noted that only 4 percent of cropland in sub-Saharan Africa is irrigated, and that most rural, food-insecure communities in the region rely on rain-fed agriculture, which, in places like Benin, is limited to a three- to six-month rainy season.
"On top of potential annual caloric shortages, households face two seasonal challenges: They must stretch their stores of staples to the next harvest (or purchase additional food, often at higher prices), and access to micronutrients via home production or purchase diminishes or disappears during the dry season," the authors wrote.
Promotion of irrigation among small landholders is therefore frequently cited as a strategy for poverty reduction, climate adaptation and promotion of food security, they said. And while the role of irrigation in poverty reduction has been studied extensively in Asia, relatively little has been written about the poverty and food security impacts in sub-Saharan Africa.
Benin demonstration sites
Benin demonstration sites
To address the lack of data, Burney and her colleagues monitored three 0.5-hectare (1.24-acre) solar-powered drip irrigation systems installed the Kalalé district of northern Benin. The systems, which use photovoltaic pumps to deliver groundwater, were financed and installed by the Solar Electric Light Fund (SELF), a nongovernmental organization."As with any water pump, solar-powered pumps save labor in rural off-grid areas where water hauling is traditionally done by hand by women and young girls," the authors said.