A smart solution for solar DC nano grid integrated with pre-paid billing and mobile application

Nowadays, renewable energy specially solar energy has become immensely popular as well as a sustainable and alternative source of energy harvesting and utilization. In Bangladesh, there are more than 4.5 million Solar Home System (SHSs) which have been installed till January, 2016 [1]. It is a natural tendency in rural areas of Bangladesh that people live in clusters and these clusters are arranged by some tens of households to few hundreds. Formation of a small scale Solar DC Nano grid would be a practical affordable solution for generating electricity and also providing basic electricity demand to these clusters. In a research work [2], it has been seen that in SHS system, more than 30% of its produced energy cannot be stored or utilized at any given time. Therefore, a smart solution for Solar DC Nano grid is needed. In this paper, a smart Solar DC Nano grid is proposed for better energy utilization. Proposed Solar DC Nano grid formed a small energy sharing (both selling and buying) cluster between SHS systems using Bi-directional DC-DC converter without large change in existing SHS systems. Pre-paid billing using mobile application is also introduced in this paper for smooth cash in and cash out after buying or selling excess energy to the neighboring SHS system. This paper illustrates the design and development of a Bi-directional DC-DC converter with Solar Charge Controller mechanism and also Pair to Pair (P2P) communication between mobile app and this device.