Variability of photovoltaic power in the state of Gujarat using high resolution solar data

The western state of Gujarat currently has the largest amount of solar capacity of any Indian state, with over 855 megawatts direct current (MWDC) among plants above 1 MWDC in size. Combined with over 3,240 megawatts (MW) of wind, variable generation renewables comprise nearly 18% of the electric-generating capacity in the state. The Central Electricity Authority has projected these wind and solar capacities will more than double by 2017. With high penetration levels of wind and solar, system operators must have access to additional resources that can help balance the net-load variability (load minus wind and solar output) and carry adequate reserves to respond to the combination of load and variable generation forecast errors. To assess the adequacy of balancing resources, and to evaluate operational practices to access these resources, system operators and planners typically perform grid integration studies. Key to informative analysis is accurate representation-spatially and temporally-of the power variability and uncertainty of solar and wind generation. This report focuses on the solar characteristics needed for a grid integration analysis, which would also include information on load, wind, and conventional generation.