Indian power sector comprises of five regional load despatch centers (RLDCs) which are northern, western, eastern, north-eastern and southern with a National Load Despatch Center (NLDC) at Delhi. Southern load despatch center (SRLDC) monitors the electric energy scheduling and load balancing of Karnataka, Andhra Pradesh, Kerala, Tamil Nadu and Pondicherry (4 states and a UT). SRLDC covers 3rd largest geographical area among other RLDCs, which includes about 22% of total country’s population and 29% of total installed capacity. Installed capacity of RE based power plants is lesser in the region (7521 MW, 15%) which illustrates lower exploitation of renewable energy potential. Taluk wise solar potential assessment is carried out for 4 states to assess the hotspots for decentralised electric energy generation

B. Method

Long term Spatio-temporal data are used to analyse the available renewable energy potential in open source GIS platform. The assessment also gives the seasonal and geographical variability of the energy resources. Long term data sets acquired from NASA SSE and Climate Research Unit (CRU) are reliable and depicts the seasonal variability which are closely correlated with ground measurement [15, 16]

1. Solar energy potential assessment: NASA SSE Global insolation datasets are obtained from a physical model based on the radiative transfer in the atmosphere considering its absorption and scattering properties. The model considers visible and infrared radiation, cloud and surface properties, temperature, perceptible water, column ozone amounts and also the atmospheric variables includes temperature and pressure measured using various satellite instruments. The long wave and shortwave solar radiations recorded in the satellite sensors along with the effecting parameters are studied to generate global insolation for different locations and durations. The 0.1°X0.1° spatial resolution SSE global insolation data derived from NASA SSE web portal (http://eosweb.larc.nasa.gov/sse/), for a period of 22 years (July 1st, 1983 to June 30th, 2005) were validated (RMSE of 10.28%) with Baseline Surface Radiation Network (BSRN) data available as daily, monthly and annual averages obtained from measured values every 3 hours [17-19]. Further, grids which essentially covers the entire southern region of the country are extracted and a geo-statistical Inverse Distance Weighting (IDW) interpolation is employed to produce monthly average Global Hourly Insolation (GHI) maps for the region. Taluk wise availability of solar potential is computed by over laying the delineated taluk boundary map.
Citation :Ramachandra TV and Ganesh Hedge,(2016). Distributed Solar Energy System, January-February 2016, pp.34-39.

* Corresponding Author :
	Dr. T.V. Ramachandra Energy & Wetlands Research Group, Centre for Ecological Sciences, Indian Institute of Science, Bangalore – 560 012, INDIA.		Tel : 91-80-23600985 / 22932506 / 22933099, Fax : 91-80-23601428 / 23600085 / 23600683 [CES-TVR] E-mail : cestvr@ces.iisc.ernet.in, energy@ces.iisc.ernet.in, Web : http://wgbis.ces.iisc.ernet.in/energy