Analyzing sub-optimal rural microgrids and methods for improving the system capacity and demand factors: Filibaba microgrid case study examined

Solar energy kiosks in developing countries are commonly designed with battery storage as daytime energy production does not coincide with an evening peak consumption. Curtailment of excess solar energy production can occur when current load and battery storage charging is not high enough during peak solar generation hours. Valuation of the options for coping with this phenomena, after a system is already built, is important for kiosk operators to continue to improve technical and economic performance. Furthermore, little real-world data is available to analyze the extent and impact of this issue, much less the available decisions for the manager of such systems when it occurs. This paper analyzes some of these phenomena and the decisions that kiosk operators can make to improve such performance. Furthermore it analyzes data-sets from a 1.8 kW solar-battery energy kiosk in rural Filibaba, Zambia to determine the level of lost energy production/curtailing that occurred in that system. Finally, potential strategies, including demand response strategies are proposed to both increase as well as shift consumption to daytime hours and ultimately increase the capacity factor of the system. Such strategies could potentially help reduce the lost production of almost 1.7MWh that was witnessed in 11 months of system usage. These strategies could also increase the revenue of the system by approx. US$810 annually. Such strategies include pricing incentives, manual demand response, and system re-design options. In the general context of operations of rural solar kiosks, this work advocates for the need to continuously improve operational as well as hardware strategy based on field-evidence.