Conclusion

The NASA SSE and NREL SUNY datasets available in user friendly formats based on time tested and realistic models provided solar radiation data on higher spatial and temporal scales The GHI datasets were collected, compared, validated and represented using GIS for the complex terrain of Himachal Pradesh. Spatial analysis of these data aided in quantifying the solar potential in the hill state with scanty surface measurements even in the district level. It is observed that Himachal Pradesh receives annual average GHI above 4.5 kWh/m²/day. The regional variations in GHI are influenced by its diverse topography as well as seasons. The lower and middle elevation zones (<3500 m) receive relatively higher GHI for a longer duration annually. However, the entire state receives considerably large amount of solar energy as demonstrated. Solar photovoltaic applications with reasonable efficiencies and costs are viable options. These could substantially improve the energy scenario by providing decentralized energy in the isolated and inaccessible pockets. The solar maps also provide necessary information for meteorology, climatology, agriculture and forestry related studies. The approach is replicable to other complex terrains of the world and the study confirms the prospects for solar based technologies to meet the impending energy crisis.