Energy Flow Strategy For A Small Scale Grid-Tied Photovoltaic System Under Net-Metering

摘要

Grid connected PV systems continue to attract investors and electricity customers all over the world. Due to interconnectionwith the utility grid, the system can glean some benefits such as selling PV electricity surplus to the utility grid or purchasing electricity fromgrid for battery storage charging at off peak hours for either self-consumption or selling back to the grid during peak hours. This paperpresent an optimal energy flow dispatch for a small-scale grid-tied PV system in order to reduce the owner’s system electricity Bills. Thesimulations take into account the available PV Energy, the battery stored energy and the grid energy. On-peak and Off-peak Electricitycharges dictated by the utility grid and a residential load from Market analysis and information System (MAISY) database are taken intoaccount for energy flow scheduling. A case study of a garage with an installed 5kWp system at Strathmore University in Nairobi, Kenyawas considered. The results analysis demonstrated that an appropriate battery size determination for a grid-tied PV system is highlygoverned by electricity tariffs and battery degradation cost.