The internet connected world demands a need for integrating the renewable energy sources and loads in the microgrid with an energy management system that is capable of monitoring, controlling and conserving energy and at the same time. This paper proposes the idea of an Internet of things (IoT) based smart Energy Management System (EMS) for a Stand-Alone Photovoltaic (SAPV) System, which acts as a closed system where all the power is generated from solar energy and either stored in batteries or utilized within the system. It has various units namely: Energy generation, Energy management and IoT. A novel constant battery operating algorithm is proposed for EMS of SAPV System. All the loads are connected through IoT and hence their status maybe monitored and controlled from remote location.