Geospatial Analysis of Solar Energy Potentials in Kaduna State, Nigeria

Abstract

This study analyzed spatially solar energy potential in Kaduna State with a view to identifying the optimum sites
for harnessing solar energy in the area. Geospatial techniques were applied to map solar energy potentials using
the ground measured and the satellite solar radiation data of the study area. Specifically, the Inverse Distance
Weighted (IDW) interpolation was applied to generate the solar radiation map using the Spatial Analyst tool in
ArcGIS software. In order to identify solar energy potential sites in the area, the Digital Elevation Model (DEM)
of the area was obtained from the Shuttle Radar Topographic Mapper (SRTM) data in ArcGIS environment.
Then, the slope and aspect maps of the area were generated from the DEM. Then, the solar radiation map, the
DEM, the slope and aspect maps were ranked based on the Analytic Hierarchy Process (AHP). Finally, the solar
radiation map, the DEM, the slope and aspect maps were integrated using weighted overlay to produce the map
of solar energy potential sites in the area. Based on the satellite data, the minimum and maximum insolation
values recorded in Kaduna State were found to be 4.47kWh/m2/day in August and 6.32kWh/m2/day in March/
April respectively. Based on the ground data, the minimum and maximum insolation values recorded in the state
were found to be 4.92kWh/m2/day in August and 7.00kWh/m2/day in March respectively. Correlation between
the ground and the satellite insolation data was found to be positive.Analysis showed that Kaduna State can be
divided into three classes in terms of solar energy potentials namely; areas of very high, high and moderate solar
energy potentials, which are spread across the 23 Local Government Areas of the state.The maximum insolation
values are found during the months of March, April and May in the study area. Therefore, these are the optimum
times for harnessing solar energy in the area.