Maximum power point tracker frequently referred to as MPPT, is an electronic system that operates the Photovoltaic (PV) modules in a manner that allows the modules to produce all the power they are capable of. MPPT is not a mechanical tracking system that “physically moves” the modules to make them point more directly at the sun. MPPT is a fully electronic system that varies the electrical operating point of the modules so that the modules are able to deliver maximum available power which varies with environmental parameters like solar radiation, temperature and wind speed. So extracting the maximum power from the panel is very important from the system efficiency point of view. Additional power harvested from the modules is then made available as increased battery charge current . It is a h/w interface b/w the solar panel & Battery . It increases efficiency of the solar panel.