A viable grid-connected PV-ECS system with load leveling function using a day-ahead weather forecast

A small grid-connected distributed power generating system based on PV panel and ECS has been developed. The system can produce power by PV panel, store energy during lower demand of load and supply the stored energy to load during higher demand. It takes a fixed amount of power from grid line and supplies to load by day and charges the ECS at night to perform the load leveling function. A procedure to estimate the output power of PV panel has also been developed by calculating solar radiation. To find out the weather dependent characteristic of the PV panel, its output in different weather conditions have been measured and compared with the estimated output. Using this weather dependant characteristic and a day-ahead weather forecast, we can estimate the output power of the PV panel in any weather condition. A simulation program has also been developed to set the optimum value of the power taken from grid line.