Around 3 billion people still live without energy with around 900 million not having access to electricity infrastructure. The only way for this to change is to either install generators in order to light up a bulb, which is considered costly based on the current rise in fuel costs or by installing a solar system with battery backup.
To solve this problem, independent Power Producers(IPP) or Utilities design mini-grid systems to be installed in remote locations who do not have access to infrastructure or where it’s difficult to install said infrastructure.
A mini-grid can make use of a single power generator or a combination of small-scale electricity generators operating in isolation to electricity grids that supply electricity to a small group of customers. System sizes differ between a couple of kilowatts up to 10 megawatts. Electricity generators in a mini-grid include PV, wind power, small-scale pumped hydro or gensets.
Distribution components of energy from the mini-grid to the user involves distribution poles, which will be either wooden or concrete poles, distribution lines, prepaid meters as well as a couple of other electrical components.
User requirements for this system is done with feasibility studies which can include residential users using gas for cooking requiring only lights and a charging point for mobile devices, larger commercial applications such as pharmacies or small grocery shops. Other application requirements include cell towers providers, agricultural processing requiring water pumps and educational institutions.
An advanced developed Energy Management System is crucial for mini-grid systems as well as some educational material for the end-user in order to ensure effective energy distribution and fair usage for every user connected to the mini-grid. Paying customers require 100% uptime for such systems based on previously mentioned feasibility studies for requirements.
One example of a mini-grid system is the Solar MD 1.5MWh ESS to be used in an agricultural application. The system includes a 630kW Sungrow Power Conversion System, 4x Sungrow string inverters offering a total of 400kWp PV power and a total of 320kW of AC-DC Chargers drawing power from either the PV or a generator to charge the batteries. The battery room is fully insulated with double glazed doors allowing for full climate control with two air conditioners installed, one of which is only for redundancy. The system also includes a 400V transformer. This mini-grid system is part of 3 phases which will allow the client to be totally independent from Utility services.