Time step simulation tool for studying the impact of solar photovoltaic penetration

Solar photovoltaic systems continue to expand across the United States due to cost competitiveness, Federal and state incentives, and Renewable Portfolio Standards (RPSs). Transmission Planners and Operators must ensure high levels of grid reliability as increasing penetration levels further affect system variability and generation intermittency. A Time Step Simulation (TSS) is developed to study increasing penetration of solar PV systems in the Dominion North Carolina Power footprint. An ideal solar irradiation shape is tested as well as normalized actual solar output profile. Results show acceptable levels of reliability for penetration levels around 1000 MW; however, there is concern regarding power flow ramping, net load reduction, and voltage variability and management.