Pre-Paid Electricity
The idea behind pre-paid delivery of electricity is to shift the onus of paying the money for electricity in time from the provider to the user. In fact, in such a scheme, since the money for electrical energy used is collected in advance, there is going to be a positive cash flow for the electrical power provider. Also, the costs associated with the generation of the bills, delivery of the bills, and disconnection of the power supply in case the bills aren't paid on time is eliminated.
Methodology
Prepaid Energy Meters are based on the principle of microcontroller application. The Microcontroller will accept the number of units recharged by the concerned department person, counts the number of units consumed by the customer and as soon as the customer exceeds the recharged amount, it will disconnect the power supply to the customer until the next recharge. Whenever the number of units in microcontroller becomes zero, microcontroller sends a signal to “Contact Maker /Breaker circuit” which is nothing but the relay and this relay cuts off the power supply to the consumer until next recharge. Figure: Block diagram of on line pre paid energy meter
As per this system, when interfaced with static electronic energy meter works as an online prepaid energy meter. The consumers and the suppliers can be benefited by using the online prepaid energy meter in the following ways:
- This system is of great advantage for the electricity department as this unit Can be utilized effectively for preventing power theft, non-payment of electricity bills etc.
- The whole process of billing can be centralized.
- Cost of manpower for billing / collection is reduced.
SMART CARD: The Most Advance Technology
- Smart Card Technology makes this system more advanced & user friendly, which has distinct advantages over the conventional form.
- Further work can be done in reading the consumed energy from energy meter wirelessly using Bluetooth technology.
When the consumer insert a smart card into the card reader which is connected in the prepaid energy meter with tariff indicator kit. Then the card reader will read the stored information and delete the information from the EEPROM IC(smart card) using the MC program. So that the smart card cannot be reused by others. Suppose if a consumer buy a card for $10, user can insert this amount through the card reader so that prepaid energy meter with tariff indicator kit will be activated. According to the power consumption the amount will be reduced. When the amount is over, the relay will automatically shutdown the whole system. There is a feature of alarm system where in the consumer is made aware about the reduced balance & so they can get it recharged .
Collection of Revenue: This is done on the vending station(s). If there is more than one station in case of a large geographical area, then all the individual stations are connected to a central database server which holds all the records.
Loading the credit revenue into the meter: Once the user has his smart card loaded with credit, he will go to the meter and bring the smart card in close proximity to the meter. The card is sensed by the meter, and then read. There are two possible functions the meter could perform once the card is sensed. Either the credit from the card is downloaded into the meter, or the credit in the meter needs to be uploaded into the meter. The user is prompted by the meter to select the right function, and the user does it by using the keys on the front of the meter.
Decrementing the loaded revenue: The amount of money loaded into the meter translates into a fixed amount of electrical energy, depending the prevailing rate for each unit of electricity. Based on this, as soon as energy consumption is recorded in the meter, the meter decrements the money loaded in a real time fashion. As the rate can change anytime, the vending software also loads the new rate for deduction to all the meters in the smart cards, as and when needed.
Providing Alarm: As the pre-loaded figure in the meter reduces due to electricity usage, the user needs to be alerted to the fact that he needs to reload credit into the meter soon or risk the disconnection of electrical power. Various methods are used like a parallel display in the users premises or just a periodic audio alarm in the users premises etc.
Disconnection: In spite of reminding the user, if he does not reload the credit into the meter, at some point, the revenue stored in the meter will reach zero. At this point, the electrical power to the user has to be disconnected. Inside the E5000, there are three 60A relays, which are in series with the load wiring. Normally, these relays are closed, but when credit reaches zero, the meter opens these contacts, thereby cutting supply to the user. This action is automatic. The relays are also of latching type, and hence even if power to the meter fails and comes back, the relay status remains open. The only way to close these contacts is to reload credit into the meter.
Security of transactions: The transactions are secured by means of: a. Secure Encrypted Memory Smart Cards. b. Record of every transaction in the database along with the identity of the person having done the transaction. c. Physical printout records generated for the user for his records.
Unloading of revenue credit: It may sometimes be necessary for the loaded credit to be unloaded and the same amount be returned to the user, e.g. If the tenant wants to vacate and move away. In this case, the vending software has the facility to unload the credit and printout a payment voucher in the name of the user.
Our clients in India are from various Industries
- Shopping Malls & Multiplexes
- Residential Townships
- Commercial Buildings
- Hotels
- Industries
Exported to
- Singapore
- Iran
- Pakistan
- Europe