In the city gas distribution (CGD) industry, metering helps in the accurate measurement of gas consumption. This data is used in billing and revenue collection to ensure proper reconciliation of accounts. Meters are used to measure the volume of gas consumed by domestic, industrial and commercial customers. They are also deployed at compressed natural gas stations.
Given the large customer base of a CGD entity, billing poses a big challenge. To this end, several CGD entities have adopted smart metering solutions. With the deployment of smart meters, billing errors can be reduced owing to minimum human intervention, resulting in accurate billing.
Consumers can also obtain detailed information of their gas usage for multiple time periods. This allows them to track their consumption patterns. Meanwhile, metering helps generate significant cost savings for the CGD utility as the field personnel do not have to visit the customer premises to take readings. Smart meters also help detect gas leakages and thefts, thereby ensuring increased operational efficiency.
Smart metering solutions
There are several solutions available in the market for converting traditional meters to smart meters. These include:
- Walk-by/drive-through solution: The walk-by/drive-through solution, uses a meter interface unit (MIU). The MIU is a radio transceiver that is attached to the meter. It communicates with the portable hand-held unit carried by the meter reader. The hand-held unit must be within a radius of 500 metres of the MIU to capture the signals transmitted by it. Once the signal is received, the meter reader transfers the data to the mobile phone through a Bluetooth connection. The mobile phone transfers the data to a data cloud using GPRS signal. Globally, two kinds of solutions are available for walk-by/drive-through operations – single mode of communication and two-way communication. In the single mode of communication, the MIU continuously sends signals at specified time intervals. As a result, whenever a meter reader is present within the radius, the hand-held unit captures and transmits the data. In a two-way communication, the meter reader sends a signal to the MIU through the hand-held unit for capturing the data. The MIU gets activated and transmits the data back.
The walk-by/drive-through solution offers several advantages. It does not require the meter reader to enter the customer premises for meter reading. Further, retrofitting is possible resulting in lower installation costs. Also, with retrofitting, no assets remain stranded. This process of meter reading is fraud resistant as the date and time stamp for meter reading is available. Further, the requirement of SIM cards for such a solution is less as one han-held unit is capable of capturing data for more than 0.1 million domestic customers and only one SIM card is required for each hand-held unit. Manual data collection and unavailability of daily data are some of the shortcomings of this system. Further, a traditional meter without a pulse provision cannot be converted into a smart meter. Such solutions are not feasible for high-rise buildings.
- Fixed meters: The fixed meter solution operates in the same way as the walk-by/drive-through solution, except that the hand-held unit is replaced by a fixed concentrator. It is the fixed concentrator that transmits data to the cloud using GPRS signal. This solution is preferred for high-rise buildings. External power supply and a suitable public space are needed for its installation. This solution can cater to 10-20 domestic customers only. Thus, a big number of fixed concentrators are required in a large geographical area. One of the major advantages of this solution is that meter readers are not required. With this solution, daily meter reading and gas reconciliation is possible. Also, real-time tampering alarms are available.
One of the key disadvantages of this solution is that an extensive radio surveillance system, with GPRS signal and 24×7 power supply, is needed in the locality where the fixed concentrator is installed. Further, this solution is not suitable for low-rise buildings.
- Point-to-point solution: In this solution, data from the meter is directly transferred to the cloud. It deploys an MIU with an inbuilt GPRS modem, which takes the pulse from the meter and transmits it to the cloud. The MIU used in this solution has an inbuilt LED camera. It takes the photo of the meter index and then transmits that image. This provision is quite useful as the image is converted into text and this text is readily available for billing. Further, tamper alarms are sounded in real time. Although it is a very efficient solution, it is quite expensive. In addition, over a period of time, the meter index becomes opaque and the camera efficiency deteriorates. Therefore, for longevity, this solution must be installed only in areas that do not face extreme temperatures.
- Prepaid solutions: It is the most advanced solution for smart metering. Indraprastha Gas Limited (IGL) is the only company in the gas segment that has installed prepaid meters. Currently, prepaid meters are operational in the Rewadi geographical area and IGL plans to install this solution in the Karnal, Meerut and Muzaffarnagar geographical areas as well. Under this system, the meter comes with an inbuilt valve equipped with a prepaid processor that communicates with the server on GPRSGSM/LoRa network. Customers can recharge the prepaid gas meters online and when the credit reaches zero, the meter valve automatically shuts off. One of the key advantages of this solution is that the customer gets real-time information about gas usage. Further, there are no cases of under-billing, estimated/wrong billing, reversal of bills or house-lock problems. With these solutions, it is easier to identify slow-moving/faulty meters. All in all, prepaid meters make the billing process much easier.
Issues and challenges
While smart metering solutions help in improving CGD operations, they come with their own set of challenges. These solutions pose an increased digital security risk as networks and servers are vulnerable to hacking. Further, customer usage can be tracked resulting in a loss of customer privacy. As third parties are also involved in monitoring of data, there is a possibility that it can be misused.
The way forward
Going forward, the adoption of smart metering technology is expected to pick up pace. Advanced meters will play a greater role. They will not only support distribution loss management, outage management, prepaid metering and net metering, but also help in the improvement of power network performance and operational efficiency, and reduction of operations and maintenance costs for utilities.
Based on presentations by Davinder Paul Singh, Additional Manager, Indraprastha Gas Limited, and Dharmendra Tomar, Deputy General Manager, Tata Communications, at a recent India Infrastructure conference