Over the past few years, smart cards have achieved a growing acceptance as a powerful tool for security and time management. If a smart card is used along with a controller which can be connected to the energy meter, the concept goes like this... For every unit of electricity consumed, the unit-charge from the card gets reduced simultaneously. When the threshold balance limit of the card is reached or goes below it, the alarm is triggered, in addition a message is sent to the consumer’s mobile phone, indicating that the card should be recharged. If the balance of the card goes zero, a relay is activated which trips open the supply to the consumer. On recharge of the card, the supply can be restored. The ultimate aim of is to put an end to the queue in the billing counter and to reduce the expenditure towards billing and system monitoring of the electricity board.
In this project smart card technique is used for paying electricity bills. The smart card used is a rechargeable card which has an IC which acts as a memory module for storing the current balance status of the card.
This smart card based prepaid electricity billing is accomplished using an Atmel AT89C51 Microcontroller. This controller is programmed to read the smart card and give the control signal to the mobile communication unit using RS-232 serial communication unit.