Design and Validation of a GSM Enabled Electricity Prepaid Meter

Abstract

This report details the working of a conventional Customer Interface Unit (CIU) for Kenya Power pre-paid meters. We study the functionality of the meters and pay particular attention to the recharge system that involves buying of tokens from Kenya Power (The vendor) and crediting the same to the customer’s account. The monetary value of the tokens is predetermined by the customers metering tariff, as issued by the vendor, and is quantified as ‘Units’ where 1KWh = 1 Unit. The process of purchasing the tokens involves a transaction through various mobile money avenues, such as Mpesa, Airtel Money, Equitel, amongst others. When a customer makes a payment to Kenya Power, an SMS is sent to their mobile phone containing a set of numbers which represent the value of units purchased. The customer is expected to input these numbers into the CIU for their electricity account to be credited with the said units. Therefore, after purchase, there must be some form of human operation in order for the recharge process to be complete. This recharge process defines the research problem and, in this report, the method currently used by Kenya Power to issue the customer units is studied in detail and an alternative method which makes the pre-paid method more efficient and faster by automating the recharge process is designed and validated. This improvement has several advantages such as simplifying the recharge process and introducing the ability to remotely recharge the electricity accounts. The method used in achieving this solution was by introducing GSM capabilities in the prepaid metering system and the outcomes of the research were noted and the proof of concept was documented. The outcomes of the research proved that the addition of a GSM module to replace the keypad in the CIU would improve the efficiency by eliminating the need to key in the token numbers in the process of recharging the customers accounts. Also, by addition of the GSM capabilities, the prepaid metering system removed the inconvenience of having to manually enter the tokens into a CIU that is, at times, at a distance especially in country homes. The GSM enabled prepaid metering system was a success and formed a basis of future study and further improvements.