Smart metering technology should be seen as just an enabler coupled with smart people and effective business processes to make the system deliver results.
Over last three decades electronic meters have been used effectively by utilities in delivering accurate billing data. Initially, the use of this technology was applied to commercial and industrial customers due to the need for accurate, reliable and more granular billing data requirements. Gradually the meter technology expanded to all customer categories. The utility started preferring electronics static meter in place of electromechanical meter due to the host of value added features provided like accurate recording of energy, storing of data with date & time stamp i.e. instantaneous, event logs, tampers, load survey/interval data, history, etc.
In electronic meters, initially the meter reading and billing was done by manual recording, followed by use of hand held devices for electronic downloading. Utilities felt the need for automated reading to provide timely bills to their high value customers. It also helped them reducing their metering/billing costs as well helped them save time and effort, and increase their overall efficiency. In early days utilities made use of PSTN networks for remote reading, which was later followed by GSM/GPRS communications technology.
In the era of Smart Grid, wherein use of information and communication technology superimposed on existing power infrastructure makes the power grid more interactive, new generation of meters with built-in intelligence and two way communication capabilities known as smart meters are getting traction in the power utilities.
Smart Meter Technology
Smart Meters are electronic measurement devices with two way communication capability used by utilities to gather regular interval data and provide customers with details of their energy usage trend thus empowering users to make judicious use of energy. It also allows utility to remotely connect/disconnect the customers as and when the need arises. Smart Meter Systems vary in design based on the use of communication technology (RF, PLC, and Cellular), application and functionalities. The Smart Meters collect data locally and transmit via a Local Area Network (LAN) to an access point or data collector. This transmission can occur as often as 15 minutes or even on a daily basis according to the use of the data. Data is transmitted via a Wide Area Network (WAN) to the utility central collection point for processing and use by other business applications like outage management systems, customer information systems, meter data management systems etc. Since the communications path is two-way, signals or commands can be sent directly to the meters, customer premise or distribution device. Figure 2 shows the basic architecture of Smart Meter System operations.
Communication network is a critical component of Smart Metering System. This should be decided based upon its availability, reliability, terrain and expectation in terms of data availability at central server. Also the performance parameters or Service level agreements (SLAs) should be met for regular reading, on-demand reading, alerts / alarms along with other desired parameter.
Utility needs to assess the suitability of the communications media based on its strategy of doing selective, city wide or nationwide smart meter rollouts. Each of the communications technology (RF, PLC or Cellular) can be further subdivided based on licensed/unlicensed bands, sub-Ghz or 2.4 GHz frequency bands, G3/PRIME PLC, GPRS/3G/LTE cellular bands. Since the communication infrastructure may be expanded to the entire utility in future, as such expandability along with scalability needs to be critically seen at the time of finalising the communication technology. Besides this, it is also important that only Smart Metering may not recover the entire cost of the communication network, hence considering support of multiple applications on same network will be a great help to get a positive return on investment and the true benefit of communication infrastructure.
With the increasing deployment of automated technologies in the implementation of smart grid infrastructure, security attacks like data hacking, introducing malware in the system and cyber-attacks are on the rise. Other vulnerabilities in AMI devices include insecure data buses, serial connections or remote debug port access. These all needs to be taken care properly and the consumer data security & privacy must be ensured. Therefore, proper cyber security measures including international best practices needs to be taken and regular monitoring, maintenance and updation software / antivirus, etc. should be ensured.
The Smart Meter technology should support multi-application besides doing only Smart Metering part. Since big investments will be made by utility in erecting a new communication infrastructure and other IT devices / servers, it is always good to have multiple applications working on the same communication network. As such a holistic view of the network architecture needs to be designed considering the judicious long term view of the communication network usage. For example in the electricity distribution utility the system along with communication technology can be used for Distribution automation, wherein the system allows for sending commands to operate grid infrastructure devices, such as distribution switches and reclosers, to provide a more reliable and efficient energy delivery system. It should also be possible to use the same system / communication network in Smart City applications like traffic Light, surveillance, water meter, etc.
To facilitate highly accurate and timely availability of data and alerts in smart metering, there is a need to define performance parameter rather than only talking on meter specifications features and functionalities. This will ensure the expected output or benefits are delivered as required by utility, besides ensuring the robustness of communication network which will help utility in making several decision in distribution segment.
The performance levels for Smart Metering system should be clearly defined for each activity with required response time such as daily readings, alerts / alarm, on-demand, outage, user interface interference, etc. This should be agreed upon by all the stake holders such as communication technology provider, meter provider and software system providers. This should be part of bid and should be signed by the successful bidder(s) so that proper measurement of the same shall be done during and after the project execution.
The greater challenge with the utilities is around support operations to manage complex network of stakeholders for smart meter management. Commercial delivery models carry huge risks as smart metering system is expensive vis-à-vis perceived benefits and there is a constant struggle to overcome cost, skill, experience and capacity challenges. With the evolution of technology, traditional skills required to manage meters and deliver support services are no longer valid. Utilities need to either train their existing resources or find alternatives to remotely manage and support meters. They need to deal with volatile energy prices, reduction of operation expenses, address regulatory pressures for increasing tariff rates and meeting ever increasing customer expectations.
While deciding to move from pilots to full scale roll out a detailed study of all the requirements and expectations from smart metering technology, advantages of service base model vs complete ownership should be evaluated. Since in the service based model, the upfront cost will be minimal and also the maintenance & operation challenges will be minimised. This will become easier for the utility to get the new system in place and slowly understand and develop the skill sets within the utility. The learnings can then be leveraged for gradual expansion for the entire set of consumer in the utility area.
The Smart metering technology is not a one-size-fits-all solution. The drivers are different and so are the solutions. By implementing, off-the-shelf product or system will not necessarily provide all the solutions to the problem. Smart metering technology should be seen as just an enabler coupled with smart people and effective business processes to make the system deliver results. The smart metering technology should be devised as per the business and overall strategic requirement of utilities. The expected output should be explicitly stated based on which the required smartness can be deployed in to the system. Considering the technology entails huge investments, the right financial model should be selected. The policy and regulation should defined accordingly and consumer engagement should be made high priority to ensure social acceptance of the new technology.
Asst. Vice President (ISEAA) in Energy SBU
Secure Meters Limited