Automatic Meter Reading (AMR) has been in vogue for high end customers for the last several decades as it offered on-line monitoring of consumer consumption and behaviour patterns.
It also allowed better revenue protection and consumer service as a result of intense periodic monitoring. Automatic grids and smart grids – neither requiring manual intervention – were the next to be deployed, offering twoway communication to execute commands and for control. Over the last 10 to 15 years, the concept of two-way communication has been extended to even low-end singlephase metering. What prompted utilities to adopt this technology for smaller consumers was primarily the ease of remote disconnection and reconnection, and the flexibility it offered consumers.
These meters were largely capable of working in a prepaid mode. This freed the bandwidth of Discom staff from metering, billing and collection (MBC) functions and allowed them to focus their energy on operation and maintenance (O&M), revenue protection and customer care.
There are a host of additional functions which can be accomplished by smart meters (as part of an Advanced Metering Infrastructure system) and the list of such functions is only limited by human imagination. Smart meters can detect first breath (Power ON) and last gasp (Power OFF) conditions and send this information to the Head End System (HES).
In this article, we aim to indicate some of the other uses of smart meters and their capabilities arising out of two-way communication which may be of interest to the designers of HES and Meter Data Management Systems.
Some of the use cases of the continuous availability of data and the other features of smart metering are
1. Automatic consumer tagging to a distribution transformer (DT): In a normal functioning system, a simple command to disconnect the smart meter installed on a particular DT may be executed. All the other smart meters installed in the adjoining areas that stop communicating automatically get tagged to that particular DT. Similarly, by disconnecting a phase on low tension (LT) [if the facility to disconnect only a phase has been enabled] the side will also tag the non-communicating consumer meters to that particular LT feeder.
2. Revenue protection by way of online availability of consumer data: Several meter data management systems (MDM) have already built in an integrated module of analytics and loss prevention based on the continuous availability of data from every individual consumer and this has been very well documented. Zero load conditions of consumers along with time stamped load survey of DT versus the sum total (Sigma) of all indexed consumers provide the time and other specific loss information for a pinpointed action plan.
3. Fault or disconnection in capacitor bank: Sudden change in the powerfactor of any DT meter or feeder meter is indicative of abrupt switching of large inductive load or fault/disconnection of a capacitor bank(s). If the drop is only of transient nature, it is indicative of sudden switching of inductive load whereas the non-transient drop would indicate a faulty/ switched off capacitor bank which may call for site inspection and restoration. Similarly, a poor power factor (PF) on a continuous basis may require installation of capacitor banks at certain load points or DTs.
4. Fault or overloading of LT lines: A significant voltage difference between the voltage at DT meter and the tail end consumer connected to this DT is indicative of overloading of this line or another line fault which needs the attention of the O&M staff of the utility. Similarly, voltage or current difference between the different phases of a DT indicates a load imbalance which needs to be attended to. Simply put, voltage regulation of LT lines from source to user end provides inputs to work out the requirements of augmentation and maintenance services.
5. Fault or overloading of feeders: If the feeders are also installed with smart meters, the similar inputs (as in the case of DT and LT lines above) would be available for the feeders. This would lead to similar diagnostics.
6. Quality of DT: Change in voltage profile of DT at no load and at full load is a certain indicator of the quality of DT. Poor regulation may be causing significant avoidable loss of energy to the utility.
7. Consumer delight and DSM measures for Discoms: Consumers can definitely take full advantage of lower rates of electricity wherever time of day (TOD) tariffs are applicable. Also, it can help the utility to offer incentives to consumers for compliance with their demand side management (DSM) initiatives. Besides, as and when the content and carriage (network owner and power supply business) is separated (as is the case in parts of north America and Europe) and there are multiple suppliers of electricity, use of smart meters will become necessary to facilitate the billings of such multiple players
8. Some of the above features may soon be realized by manufactures of MDM or other analytical tools attached to MDM.
However, the possibilities for the future are really endless with the integration of relays and switches with smart meters. Consider some of the possibilities of a well-integrated smart home:
- Switching on and setting the temperature of your room well before you arrive home will result in increased comfort and energy saving.
- Lowering the temperature of your fridge to chill your drinks minutes before you arrive.
- Switching on the microwave at your command to prepare your food just when you arrive home.
- Continuous surveillance of your home or your child’s room through a webcam integrated with your smart meters.
In conclusion, smart meters, while already performing several innovative functions, can be extremely effective in reducing aggregate of technical and commercial (AT&C) losses besides continuously monitoring the network health in Asian countries.
As and when the above happens, a smart meter will not only become an electricity meter with much flexibility, but also become a true controller and watchdog of smart homes. The deploying utilities can then in turn become universal integrated service providers rather than just being an electricity supplier.
About Arun Kumar Kanchan and Ravindra Kumar Jain:
Arun Kumar Kanchan has been CEO/Director of BSES Rajdhani Power, BSES Yamuna Power and Torrent Power (Surat). He is currently working as Executive Director of Mercados Energy Market India and is spearheading monitoring of the implementation of the UDAY programme at Uttar Pradesh Power Corporation, Shakti Bhavan, Lucknow.
Ravindra Kumar Jain is currently working as superintending engineer and is in charge of the metering, billing and collection cell at Uttar Pradesh Power Corporation Limited (UPPCL). He is also staff officer to the Chairman, UPPCL as a techno-commercial advisor.