Advanced metering infrastructure (AMI) is a prerequisite for smart meters and the basic building block for a smart grid. As utilities are moving towards the implementation of smart grid technologies, the adoption of AMI is increasing.
A typical AMI system comprises smart meters, data concentrator units (DCUs), a head-end system (HES), and a meter data acquisition system (MDAS) which communicates over a bidirectional wide area network (WAN), neighbourhood area network (NAN)/field area network (FAN) and home area network (HAN). Multiple smart meters in a locality can be connected to a DCU for sending aggregated data to the HES of the utility through power line communication or wireless communication. The MDAS and meter data management system (MDMS) together help manage the large volumes of data generated by smart metering systems, process the information to generate meaningful results, as well as integrate the metering systems with enterprise-wide systems while acting as an interface for various applications within the utility. Appliances such as TVs, refrigerators, air conditioners, etc., can be a part of HAN, which can be controlled through a smart meter.
Standards and specifications
In September 2016, the Central Electricity Authority (CEA) released the “Strategy for Roll-out of Smart Meters by States/Union Territories” report, which suggests the use of radio frequency-based network, power line carrier or cellular network, or a combination of these to develop the communications infrastructure of smart meters. The CEA also released the “Functional Requirements for Smart Utilities” report in August 2016, focusing on AMI system requirements, communications infrastructure and network security.
In August 2015, the Bureau of Indian Standards published the new Smart Meter Standard IS 16444: AC Static Direct Connected Watthour Smart Meter – Class 1 and 2 Specification covering single-phase energy meters and three-phase energy meters with net metering facility. Another standard, IS 15959: Data Exchange for Electricity Meter Reading, Tariff and Load Control – Companion Specification was revised and published as IS 15959: Part 2 – Smart Meter in March 2016.
In recent years, the government has been focusing on promoting the installation of smart meters through various policy initiatives and programmes. The tariff policy (amended in January 2016) stipulates the installation of smart meters to enable time-of-day metering, reduce theft and allow net metering. As per the revised tariff policy and the Ujwal Discom Assurance Yojana (UDAY), smart meters should be installed for all consumers with consumption exceeding 500 units per month by December 31, 2017 and for consumers with consumption exceeding 200 units per month by December 31, 2019. Besides, all the 10 smart grid pilot projects (shortlisted by the Ministry of Power [MoP] in 2012), which are currently under implementation, have AMI as an important feature. The Integrated Power Development Scheme also envisages the installation of smart meters in towns with supervisory control and data acquisition system.
Under UDAY, of the targeted installation of over 5 million smart meters for consumers with consumption above 500 units per month, only 132,774 meters have been installed, indicating 3 per cent coverage. Meanwhile, for consumers with consumption above 200 units per month and up to 500 units per month, smart metering installations stand at 155,179 as against the target of 17.5 million, indicating about 1 per cent coverage.
Recently, Energy Efficiency Services Limited issued a mega tender for the procurement of 5 million smart meters on behalf of Haryana and Uttar Pradesh. With a number of states joining UDAY, more such tenders for smart meter procurement are expected in the coming months. In the past, smart metering pilot projects have been implemented by CESC Limited, Tata Power-Mumbai, Tata Power Delhi Distribution Limited and Reliance Power.
Challenges and the way forward
The high cost of smart meters is a key impediment that hampers their adoption by utilities. As per industry estimates, the cost per meter is around Rs 5,000 at present. The bulk tenders proposed by the MoP may help in reducing the cost to some extent.
Regarding the roll-out strategy for smart meters, the India Smart Grid Forum suggests that discoms prioritise certain customer categories and/or locations for the deployment of AMI in phases. For instance, customers with high monthly consumption (over 1,000 units in the first phase, and over 500 units in the next and so on) can be prioritised. Alternatively, feeders/pockets with high aggregate technical and commercial loss areas (over 15 per cent) or feeders/towns with high annual energy sales can be covered in the initial phases. The utilities should ensure that all new meters conform to the latest amendments of IS 16444 and IS 15959. Further, discoms may select the communications technology according to their needs and requirements.
Going forward, the adoption of smart metering technology is expected to gain pace driven by the government’s support.