DC micro grid with centralized solar generation and decentralized storage is the simplest, reliable, cost effective, scalable and highly efficient solution to provide access to electricity to people living without access to electricity. DC micro grid uses array of solar panel connected in series to generate power at 230 V DC, which can be transmitted over distance of 1-2km similar to 230V, AC distribution line using a 2 core cable and supporting poles. Houses are connected to the distribution line through junction boxes mounted on poles. The micro grid charge controller installed in each house steps down 230V, DC to 14V, DC which is used to charge the storage battery and power the energy efficient DC loads in house. In the day time, the controller installed in each house draws power from the grid to charge the battery and power the DC loads. During night the controller supply power to the DC loads from stored energy in the battery. The micro grid charge controller has an integrated prepaid meter that monitors the energy consumption of respective house. A recharging unit installed in entrepreneurs house connected to the network enables recharging of prepaid charge controller using the same distribution cable without interrupting the usage of power by the connected loads.
Sustainable and Scalable Business Model
DC micro grid prepayment solution ensures that the micro grid entrepreneur collects the money from the end users for their usage of energy from the grid. Each user purchases advance energy credit from the micro grid entrepreneur by paying a nominal amount. After purchase of energy credit, the micro grid charge controller installed in the consumers house gets connected to the grid. The micro grid charge controller monitors the energy consumption and disconnects from the grid when the energy credit is over.
• Higher efficiency compared to AC Micro grid
• Can supply power for household need (Light, TV, Fan, Mobile charging), community need (Water pumping) and need of small business establishments
• Does not require highly skilled manpower for installation, operation and service
• Highly reliable due to absence of Inverter and centralized storage
• Less investment for entrepreneur compared to AC micro grid as the entrepreneur will not invest in Battery and inverter
• Lower initial investment for household compared to individual solar home system