Meter data is a storehouse of valuable information for a distribution utility. A smart meter precisely records consumer data, which can be used to predict the load curve of consumers and detect power theft, among other things. It is critical to acquire data through meters while ensuring its integrity and making it available in a cost-effective manner for last mile analysis.
A meter data acquisition system can be split into two broad categories: field devices and services; and software, hardware and other services. Field devices and services primarily include electricity meters and communication systems. The available network is a key determinant of the communication technology deployed by a utility. The network decides the cost of the communication system as well as the possible outcomes from the latter. Meanwhile, the software, hardware and service category comprises the head-end system, the meter data management system and enterprise applications, including billing, open metering system, demand response and analytics.
Key considerations
Various technologies are available for acquiring data from smart meters. A utility can adopt different technologies in different pockets of its distribution area. Some of the available communication technologies are ZigBee, wM-Bus, Z-Wave, Bluetooth, wireless, Wi-Fi, power line carrier communication and GPRS. These technologies vary in their communication range and are suitable for different network sizes (in terms of number of meters and nodes).
The communication range is one of the key considerations in the adoption of a communication technology. The ideal communication range for a particular region is decided based on its geography and type of consumers. This is because spectrum availability and operating frequency, which are critical for the smooth operation of any communication technology, vary from country to country. Moreover, power consumption of the chosen technology must suit the region.
The cost of a communication technology is another important consideration in its adoption. It is necessary for a technology to be economical for mass deployment. Apart from this, the cost of meters and operations and maintenance, among other things, needs to be taken into account.
The ability to maintain the integrity of data and ensure its security is another critical consideration in deploying a data acquisition technology. The technology must be insensitive to external interference like data encryption and data hacking. With the surfacing of innovative tampering methods, it has also become important to protect the data from CD-based tampering, surge-based tampering and switch-based tampering. If the data is tampered with while being transferred from the meter, the original data will be retrieved. In the case of data collection for the purpose of billing, ensuring accuracy is all the more important.
Meanwhile, it is important to ensure the interoperability of acquisition technologies. This would reduce the dependence of the utility on a particular vendor. There is a need for defining standard protocols for devices to ensure interoperability. Besides, these standards must have worldwide acceptance. It is also necessary to ensure that the technology is compatible with the existing infrastructure. It must be easy to understand and customise for accommodating new ideas and programmes. Ensuring scalability of the technology is also vital for operations.
Approaches for data acquisition
Many-to-many
Under this approach, each interface between meter data collection systems and the utility’s other systems is developed individually as a centralised meter data repository is missing. There is a lot duplication of work as each utility system performs the task of integrating meter data. Essentially, each result of automated meter reading (AMR) or advanced metering infrastructure (AMI) system connects with each utility system independently.
Customised core business systems
In this approach, the utility customises the core business systems to accommodate the AMR or AMI data. The new functions needed to manage the data are added to the core business systems of the utility. These include customer information systems (CIS), open metering systems and energy management systems. For instance, in order to use the data exported by AMR for CIS, the latter is modified to receive data in a compatible format. However, making changes to core business systems is expensive and complex. This also results in patchy, less robust and more difficult to maintain utility systems. Apart from this, it reduces the flexibility of data use, as a new AMR system would require fresh customisation of the core business.
Meter data repository
In this approach, a meter data repository is set up to store the data received from AMR systems. The data repository makes the data acquisition process more robust as it isolates utility systems from the functioning of the AMR systems. One of key advantages of this approach is that utilities can upgrade the AMR systems without undertaking changes in the core business systems. However, there is duplication of work involved as the same data processing requirements are handled individually by various utility systems. A single interface point for AMR data encourages the integration of the meter data repository with more utility systems. However, diverse requirements from other systems make the use of a repository essential.
Vendor-neutral meter data warehouse with pre-processing capabilities
One of the popular approaches for utilising meter data is to build a vendor-neutral meter data warehouse with pre-processing capabilities. A data warehouse stores transaction data and is structured for undertaking basic analysis to respond to diverse queries from various utility systems. This ensures consistency in the methods deployed for pre-processing the data. However, it is critical to ensure data security to obtain robust pre-processing outcomes.
Integration using enterprise service bus
Another approach that is widely deployed for processing the meter data is the use of an enterprise service bus. Under this, data from the AMR and AMI systems is conveyed to a meter data management system, which transfers it to an enterprise bus. The enterprise bus then makes the data available for utility systems.
Summing up
To conclude, a host of technologies are available for meter data acquisition as well as for making the data available to the utility system. However, it is critical to adopt the technology that is best suited to a particular region and is at the same time robust, cost effective, easy to understand, and scalable. In addition, ensuring the integrity of meter data throughout the data acquisition process is imperative.
Based on a presentation by Mitul Thapliyal, Senior Principal and Practice Leader, Energy Utilities & Smart Cities, Infosys, at a recent Power Line conference