CESC has come a long way in terms of metering improvements. After the computerisation of its high tension (HT) and low tension (LT) billing systems in 1970, it moved to the use of static meters for both segments in 1995. This was followed by the use of meter reading instrument data for billing and analytics. These changes led to benefits like the easy detection of metering defects, pilferage elimination, error-free meter reading and access to user information.
CESC introduced automated meter reading (AMR) in 2010 in order to shorten the “meter reading to cash” period, reduce meter overheads, and speed up the rectification of meter defects. The deployment of AMR offered several benefits, such as faster payment realisations and metering defect rectification, and the reduction of unsuccessful meter readings to zero. Further, the success rate of bill reading for the HT segment was enhanced to 99 per cent through AMR implementation.
AMR in DTs
The success of AMR in the HT segment prompted CESC to replicate the changes in the distribution transformer (DT) meter segment as well. The primary objective was to facilitate energy audits in its distribution segment, besides enabling condition monitoring, capex optimisation and outage management improvement. AMR has been deployed in around 80 per cent of the DTs, and the target is to reach 100 per cent by the end of 2015-16. CESC has also developed in-house modules for analytics and outage management systems for analysing the retrieved data. The AMR success rate in the DT segment is 97-98 per cent.
CESC has been able to maintain its success rate over the years after having developed a robust IT application to detect any modem irregularities and strong service level agreements and annual maintenance contracts with mobile service providers and hardware suppliers respectively.
AMR in the LT-WC segment
Through a pilot project, CESC introduced AMR in the LT-whole current (WC) segment to deal with the issues in managing yearly meter growth with the existing meter reader strength as well as bill reading from meters located inside the metal pillar boxes on pole tops in pilferage-prone areas. The company installed smart meters with point-to-point (P2P) GPRS for two sets of LT consumers: Indus Towers and key individual customers. The success rate here is 100 per cent for bill reading, 90 per cent for hourly data and over 95 per cent for daily audit data. However, there are issues related to interoperability. P2P GPRS is not applicable in this segment due to cost ineffectiveness, space constraints and difficulty in managing it at the site. Further, there is a mix of meters in the circuit, as some meters are still of the electromechanical type. There is also a lack of support for value additions to existing AMR solutions.
AMI in the WC segment
Advanced metering infrastructure (AMI) ensures quality, capability and upgradability. Although it has a very high cost of ownership, AMI has the ability to support future needs, manage peak demand and bring about a reduction in opex. For CESC, a 100 per cent roll-out of AMI is not possible due to financial constraints. However, it intends to use its rich optic fibre network as a communication backhaul and install a radio frequency (RF) mesh multi-purpose canopy. The deployment will be need-based and scattered, and the meters will be installed in “hang and run” mode.
Currently, CESC is involved in three pilots: two based on AMI and one on a smart grid. The first pilot based on AMI was successfully completed in February 2015. About 25 meters were randomly installed on a 1 square km area using an RF mesh (865-867 MHz) as the communication technology. The objective was to check whether the communication canopy supported the scattered and need-based deployment of smart meters. The second AMI-based pilot was initiated in January 2015, with the objective of checking the communication success rate for overhead and underground networks. Currently, 60 meters from the same manufacturer have been installed, covering three DTs. The smart grid-based pilot was launched in June 2015 with a similar objective. The utility also considered remote monitor unit (RMU) automation in this pilot. The aspect of interoperability has been dealt with by deploying meters from two different manufacturers.
Besides these pilots, CESC also intends to collaborate with an international communication vendor for another pilot. The evaluation of these pilots will be based on integration requirements and issues, features and functionalities of home electronic systems, interoperability, strength of the communication canopy, the number of devices needed to cover the pilot area and latency issues.
CESC has been proactive in adopting new technologies in the areas of AMR and AMI. The company expects that in the next 10 years, smart meters will support its initiatives in data analytics, dynamic distribution loss management, customer centricity, containing of metering overheads, power network performance and operational efficiency improvements, limiting repairs and maintenance expenditure, and value additions. n
Based on a presentation by Santosh Chattopadhyay, Deputy Manager, CESC Limited, at a Power Line conference