Optimization of energy flow in a microgrid application with a photovoltaic electricity supply

A microgrid is a local energy grid that generates electricity through a combination of energy sources, operates while connected to the main grid, but it can also operate independently. Microgrids can be powered using wind turbines, generators, batteries, or solar panels. In case of emergency, a microgrid provides backup from the main grid in times of crisis like storms or power outages, also it can be used to reduce the energy consumption from the main grid. This paper presents optimization of a battery schedule in a microgrid application when is used in as island mode (disconnected from the main grid) with a photovoltaic electricity supply, battery and inverter. The data used for the problem formulation include the photovoltaic energy production in 24 hours for 3000 houses of California state with solar panel power output 165W, and 200W, battery capacity with 100MW, 150MW, and 200MW. A winter day and a summer day are considered in this study for the simulations. One object function with six’s different scenarios is used to test the problem for minimization of the consumed energy from the main grid. The MATLAB solver fmincon from Optimization Toolbox is used for the calculations. The data about the consumption of the houses are taken from nanoHUB platform, and the production results of the solar panels are from GridLab-D tool. The obtained results show that a reduction of energy costs for the end user can be achieved by means of optimal battery schedules, as well as that the energy consumption from the main grid can be minimized. The presented approach is promising and it can be applied successfully to real microgrids