High energy costs for pumping groundwater for irrigation and a lack of viable and durable energetically efficient and environmentally sound pumping technologies that Nepali farmers can reliably access.
While market prices for solar panels continue to decline, European-sourced pumps and their controllers are not getting any cheaper. Without government subsidies farmers are not willing to purchase solar pumps. CSISA embarked on the rapid development and testing of a 1 kilowatt Sasto Solar Sichai (cheaper solar irrigation) pumps that could be used for the irrigation of field crops like wheat, maize and rice. Using off-the-shelf 48 volt DC motors and charge controllers that were already being used in the transport sector in Nepal (e.g. battery-powered three wheelers) and connected to 2-3 inch centrifugal pumps and powered by 1,200 watt solar PV panels, CSISA had brought down the cost of a 1 kilowatt system from over US$ 2,500 to less than US$ 1,500.