Development of Energy Payment System with Remote Switching for Multi-Apartment Occupants

Electricity bill sharing among occupants of multi apartment buildings in Nigeria is often based on equal cost allocation, a practice that leads to billing disputes, unpaid charges, and unjust cost sharing among users with unequal consumption patterns. This study develops and evaluates an energy payment system combined with a remote switching mechanism to ensure fair billing and enforce payment compliance. The methodology integrates multiple digital energy meters to independently measure consumption for each apartment and shared facilities, followed by a billing template that redistributes energy consumption based on recorded units to account for meter calibration errors. A control module comprising an Arduino Uno, SIM800 GSM module, and relay based switching unit was designed to remotely disconnect defaulting occupants through Short Message Service (SMS) commands. Experimental validation on a simulated three-apartment setup showed that the system accurately calculated individual bills based on proportional energy use, resulting in energy charges of ₦3,093.43, ₦4,211.69, and ₦2,694.95 for the three apartments respectively, instead of equal sharing. The remote switching module successfully disconnected and restored supply to specific apartments without affecting others. The results demonstrate that the proposed system provides transparency in billing, prevents disputes, and enforces accountability, thereby improving revenue recovery and consumption discipline in multi apartment buildings.