Suitability mapping framework for solar photovoltaic pumps for smallholder farmers in sub-Saharan Africa

Abstract

As solar panels become more affordable, solar photovoltaic (PV) pumps have been identified as a high potential water-lifting technology to meet the growing irrigation demand in sub-Saharan Africa (SSA). However, little is known about the geo-spatial potential of solar-based PV pumping for irrigation taking into account not only solar radiation but also the availability of water resources and linkage to markets. This study developed a suitability framework using multi-criteria analysis in an open source geographic information system (GIS) environment and tested it in the case of Ethiopia. The accessibility of water resources was the driving factor for different scenarios. Suitability results following the groundwater scenarios showed good agreement with the available referenced well depth data. Comparing the suitability maps with available land use data showed that on average 9% (96 103 ha) of Ethiopian irrigated and 18% (3,739 103 ha) of rainfed land would be suitable for solar PV pump irrigation. Furthermore, small solar PV pumps could be an alternative water-lifting technology for 11% of the current and future small motorized hydrocarbon fuel pumps on smallholder farms (2,166 103 ha). Depending on the technical pump capacity, between 155 103 ha and 204 103 ha of land would be suitable for solar PV pumps and provide smallholder farmers with the option to either pump from small reservoirs or shallow groundwater. With the ongoing interest in development for smallholder irrigation, the application of this model will help to upscale solar PV pumps for smallholder farmers in SSA as a climate-smart technology in an integrated manner.