Abstract: - The solar collector's output over its entire working life is 79.94 percent and 498,225kWh, respectively. Reduced reliance on grid supply and/or fossil-fuel based generator sets during hot water demand A proper harnessing of solar (radiant) energy is a potential solution to adequate and sustainable electricity supply problems in most developing countries. Because of our overreliance on fossil-fuel-based oil, carbon dioxide (CO2) emissions into the atmosphere have increased exponentially, causing extreme environmental pollution and ozone layer depletion. The solar collector's output over its entire working life is 79.94 percent and 498,225kWh, respectively. Reduced reliance on grid supply and/or fossil-fuel based generator sets during hot water demand A proper harnessing of solar (radiant) energy is a potential solution to adequate and sustainable electricity supply problems in most developing countries. Because of our overreliance on fossil-fuel-based oil, carbon dioxide (CO2) emissions into the atmosphere have increased exponentially, causing extreme environmental pollution and ozone layer depletion This paper aims to adapt a readily available radiant energy supply to solar water heating and determine potential economic advantages for Covenant University campus inhabitants who use it in domestic applications. The microcontroller-based active solar water heating system (ASWHS) is designed to absorb radiant energy via solar collectors and store it as hot water in a water tank through a direct current (DC) circulation pump operated by a standalone photovoltaic (PV) system. The design also includes an auxiliary electric heater that is used only when radiant energy is insufficient. The importance of the ASWHS for domestic water heating is demonstrated through a case study. The ASWHS with a high payback period of 15 years records the maximum design efficiency and expected energy periods; and the ASWHS' lower unit cost (US$0.01/kWh) makes it more economically viable than the grid supply's unit cost (US$0.18/kWh) for the same amount of energy consume.Keywords-ASWHS, CO2 emissions, microcontroller, solar energy, solar collector, unit cost.