Metering plays a crucial role in the city gas distribution (CGD) industry. It ensures the accurate measurement of gas consumption, which is billed for revenue collection. This helps in the proper reconciliation of accounts. Meters are used to measure the volume of gas consumed by domestic, industrial and commercial consumers. These are also installed at compressed natural gas stations. However, the existing metering technologies and equipment are prone to human errors and wear and tear. Incorrect meter readings lead to leakages, which creates a gap between the gas supplied and consumed.
Over the years, with technological advancements, various metering solutions have emerged and significantly changed the way the CGD business is being conducted in the country. A number of CGD players have adopted smart metering solutions to increase their competence and serve customers better. One such player is Indraprastha Gas Limited (IGL), which has been operational in the national capital region (NCR) and neighbouring-areas for-a-long-time now. A look at the metering solutions adopted by IGL…
IGL has been one of the early users of automatic meter reading (AMR) systems in the CGD business. Some of the key benefits of AMR systems are timely collection of readings, updated consumption data for detailed analysis, accurate billing and regular interface with SAP for invoicing purposes. They eliminate the need for manual reading, thereby minimising the scope for human error. The AMR solution was primarily adopted by IGL to provide a centralised online monitoring system for gas supplies. Another key factor driving AMR adoption was the need for a reliable consumption data collection mechanism to ensure billing accuracy with minimum human interference. The system also helped the company overcome perennial issues of locked doors of houses at the time of manual reading and faulty bills due to estimated billing. In the domestic segment, there are two types of AMR solutions – fixed solutions and walk-by/driveby solutions. In a fixed AMR solution, meter interface units are attached to gas meters to capture meter readings and transmit them to a data concentrator. A data concentrator relays the data to a server wirelessly over GPRS/4G/global system for mobile communication/lowpower WAN technology. Data from the server can then be integrated with SAP for billing purposes. In walk-by/drive-by solutions, meter interface units are attached to existing gas meters to capture meter readings and transmit them to a data collector, which in turn relays it to an Android/iOS device over Bluetooth. The data collector device is carried by individuals as they walk/drive through a designated area. The device captures the readings depending on the line of sight. The data is relayed to the server wirelessly to generate bills. For the industrial and commercial segments, the AMR solution comes with a modem. The meter interface units are attached to gas meters or flow computers to capture readings and transmit the same through GSM/GPRS/4G/LoRa to the main server on a daily basis. The data collected from the server is integrated with SAP to generate bills.
An emerging metering trend in the CGD sector is smart prepaid gas meters. These meters not only measure the gas consumption (through gas flow), but also use wireless communication to connect to a local or a wide area network that enables infrastructure maintenance, remote location monitoring, and automatic billing by the CGD company. Besides, these meters have a valve to stop the gas flow when the credit in the prepaid account reduces below a certain level. These meters are used to establish connection with cloud server every day at a scheduled time. The cloud server gathers required information (usage and tamper) from connected meters. It checks the available credit limit from IGL server against consumed volume for each end consumer. If the credit limit of the consumer is less than 10 per cent, the cloud server sends message to registered consumer’s mobile number about low credit limit. The IGL payment gateway processes the payment information and sends details to IGL server if the consumer recharges his account. However, in case the consumer fails to do so, the gas meter valve is shut off. This calls for operator to visit site in order to reset the valve manually with valid code whenever payment is credited.
Key functions of smart gas meters
With fast changing technologies, innovative solutions are coming up in the smart metering space. These include ultrasonic meters, thermal mass flow meters and positive displacement flow meters. The basic elements of a thermal mass flow meter include main body, capillary, laminar flow element, and a flow sensor chip, which is installed in the bypass channel. The micro-thermal flow sensors measure the flow rate as a function of temperature difference. A precision power supply delivers constant heat to the flow sensor. When there is no flow, both temperature sensors measure the same temperature. However, in case of presence of flow, the measured temperature is the difference between the two sensors and is proportional to the mass flow rate. Further, there are various technologies available for communication in smart gas metering practices such as walk by system, data concentrator, global system for mobile communications and general packet radio services-based communication, and Narrowband Internet of things (NB-IoT).
Communication technology for gas metering
IGL became the first CGD company to deploy smart metering technology in the country by installing prepaid smart gas meters at the Rewari district in the state of Haryana in 2019. These smart meters, provided by Genesis Gas Solutions, in partnership with Tata Communications’ LoRaWAN IoT network enables IGL’s customers to monitor their gas use more accurately in real-time against available credit. As of February 2020, IGL had installed 200,000 domestic AMR meters across its network, 2,500 such units in the industrial and commercial segment, and 11,500 prepaid meters outside the NCR. Going ahead, the company plans to install 54,000 prepaid smart meters in the domestic segment along with prepaid meters in the commercial segment and industrial.
A number of challenges, however, still remain in the sector. Smart gas metering is quite different from smart electricity metering. While electricity meters are easily powered through the main line and can rely on an existing electric network, smart gas meters need to rely on a battery-powered and wireless infrastructure as they are prone to gas related accident risks. In addition, there are issues pertaining to the shortage of skilled manpower. Besides, there are limited domestic vendors available for smart meters, limiting the scale of adoption.
Business initiatives such as the adoption of smart metering systems provide a utility with an operational edge over its competitors through efficiency gains. The timely billing of services, effective revenue collection and enhanced consumer experience is a win-win for both consumers and the utility. In current times, marked by fast changing technologies and innovative ways of conducting business, smart metering is a necessity for a traditional utility aiming to transform into a smart utility.
By Raman Srivastava
Based on a presentation by Raman Srivastava, Chief General Manager, Instrumentation & Automation, Indraprastha Gas Limited at the 15th annual conference on City Gas Distribution in India. Mr Srivastava has over 25 years of experience in leading, managing and implementing large instrumentation and automation, and O&M projects and business solutions in the gas sector. Under his guidance, prepaid metering for domestic gas customers has been successfully implemented in Rewari. He has also revolutionalised the company’s billing system with the implementation of the AMR system.