Advanced Metering Infrastructure (AMI)
What is Advanced Metering Infrastructure (AMI)?
Advanced metering infrastructure (AMI) is a composite technology composed of several elements: consumption meters, a two-way communications channel, and a data repository (meter data management). Jointly, they support all phases of the meter data life cycle — from data acquisition to final provisioning of energy consumption information to end customers (for example, for load profile presentment) or an IT application (such as revenue protection, demand response, or outage management).
Advanced Metering Infrastructure (AMI) refers to systems that measure, collect, and analyze energy usage and communicate with metering devices such as electricity meters, gas meters, heat meters, and water meters, either on request or on a schedule. These systems include hardware, software, communications, consumer energy displays and controllers, customer-associated systems, meter data management software, and supplier business systems. Government agencies and utilities are turning toward advanced metering infrastructure (AMI) systems as part of larger “smart grid” initiatives. AMI extends automatic meter reading (AMR) technology by providing two-way meter communications, allowing commands to be sent toward the home for multiple purposes, including time-based pricing information, demand-response actions, or remote service disconnects. Wireless technologies are critical elements of the neighborhood network, aggregating a mesh configuration of up to thousands of meters for backhaul to the utility’s IT headquarters. The network between measurement devices and business systems allows the collection and distribution of information to customers, suppliers, utility companies, and service providers. This enables these businesses to participate in demand response services. Consumers can use the information provided by the system to change their normal consumption patterns to take advantage of lower prices. Pricing can be used to curb the growth of peak demand consumption. AMI differs from traditional automatic meter reading (AMR) in that it enables two-way communication with the meter. Systems only capable of meter readings do not qualify as AMI systems.
Figure 1 shows the building blocks of AMI. The customer is equipped with advanced solid state, electronic meters that collect time-based data. Meters include all three types - electricity, gas, and water meters. These meters have the ability to transmit the collected data through commonly available fixed networks such as Broadband over Power Line (BPL), Power Line Communications (PLC), Fixed Radio Frequency (RF) networks, and public networks (e.g., landlines, cellular, paging). The meter data are received by the AMI host system and sent to the Meter Data Management System (MDMS) that manages data storage and analysis to provide the information in a useful form to the utility. AMI enables two-way communications, so communication from the utility to the meter could also take place.
Benefits of AMI
AMI provides benefits to consumers, utilities, and society as a whole.
- Consumer Benefits: For the consumer, this means more choices about price and service, less intrusion, and more information with which to manage consumption, cost, and other decisions. It also means higher reliability, better power quality, and more prompt, more accurate billing. In addition, AMI will help keep down utility costs, and therefore electricity prices. And, as members of society, consumers also reap all the benefits that accrue to society in general, as described below.
- Utility Benefits: Utility benefits fall into two major categories, billing, and operations. AMI helps the utility avoid estimated readings, provide accurate and timely bills, operate more efficiently and reliably, and offer significantly better consumer service. AMI eliminates the vehicle, training, health insurance, and other overhead expenses of manual meter reading, while the shorter read-to-pay time advances the utility’s cash flow, creating a one-time benefit. And consumer concerns about meter readers on their premises are eliminated. Operationally, with AMI the utility knows immediately when and where an outage occurs so it can dispatch repair crews in a more timely and efficient way. Meter-level outage and restoration information accelerates the outage restoration process, which includes notifying consumers about when power is likely to return. Using AMI, the utility can receive significant benefits from being able to manage customer accounts more promptly and efficiently, starting with the ability to remotely connect and disconnect service without having to send personnel to the customer site. Similarly, many maintenance and customer service issues can be resolved more quickly and cost-effectively through the use of remote diagnostics. And AMI enables new programs and methods for creating and recovering revenue such as distributed generation and prepayment programs. AMI also provides vast amounts of energy usage and grid status information that can be used by consumers to make more informed consumption decisions and by utilities to make better decisions about system improvements and service offerings. Instead of relying on rough estimates, engineers armed with AMI’s detailed knowledge of distribution loads and electrical quality can accurately size equipment and protection devices, and better understand distribution system behavior. This huge increase in valuable information helps the utility:
- Assess equipment health
- Maximize asset utilization and life
- Optimize maintenance, capital and O&M spending
- Pinpoint grid problems
- Improve grid planning
- Locate/ identify power quality issues
- Detect/reduce energy theft
- Societal Benefits: Society, in general, benefits from AMI in many ways. One way is through improved efficiency in energy delivery and use, producing a favorable environmental impact. It can accelerate the use of distributed generation, which can in turn encourage the use of green energy sources. And it is likely that emissions trading will be enabled by AMI’s detailed measurement and recording capabilities. A major benefit of AMI is its facilitation of demand response and innovative energy tariffs. During periods of high energy demand, a small reduction in demand produces a relatively large reduction in the market price of electricity. And reduced demand can avoid rolling blackouts. According to Edison Electric Institute (EEI), the direct costs (e.g. power costs) of rolling blackouts in California have been estimated at tens of millions of dollars. Business and consumer losses may be many times higher. Hence, a modest demand response capability could produce a societal benefit worth billions of dollars. The benefits accrued may vary depending on the type of demand response programs initiated. For instance, demand response distributed to the individual premise in forms like thermostats and pool pump control allows the load to be reduced without sacrificing consumer satisfaction. However, even just shifting demand away from peak hours through time-of-use tariffs can have major benefits, including the reduced cost to both utilities and consumers by deferring building new, expensive peak generation facilities. There is also a societal fairness issue that AMI addresses. Full deployment of AMI results in the elimination of old and obsolete electromechanical meters that tend to slow down as they age. Modern AMI meters maintain their accuracy over time, resulting in a more equitable situation for all consumers. In addition, modern meters are self-monitoring, making it easier to identify inaccurate measurements, incorrect installations, and, especially, electric energy theft.
- Added Benefits when AMI serves as a Modern Grid Platform: going beyond AMI to achieve a truly modern grid produces additional large improvements in the operations of an electric utility. The list of benefits includes:
- Greatly improved outage management system (through links with GIS and real-time consumer status)
- Improved system planning process and results
- Improved distribution asset management programs including equipment health assessment and condition-based maintenance
- Advanced distribution management systems (distribution automation, integrated operation of DR (and DER), micro-grid operation, self-healing, etc.)
- Improved mobile workforce management and operations
- New opportunities for consumer choice and new retail services
- Improvements to power quality issues
- Reduced environmental impact
- Distribution system support of transmission operations (transmission congestion relief, voltage support, loss reduction)
Challenges in AMI Implementations
AMI implementations are massive transformation programs that typically require a timeframe of between 3-5 years for a full-scale rollout depending on the customer base of the utility. The following are key challenges in any AMI implementation:
- Cost: Deploying smart meters requires huge capital investment and hence it is crucial that the utility company is confident of successful implementation.
- Data Privacy: There are many concerns related to the privacy of consumption data being raised as Smart Meters are installed at more and more locations. The meters’ data can be mined to reveal details about customers’ habits like when they eat, how much television they watch, and what time they go to sleep. The retention and storage of this data make it vulnerable to security breaches as well as government access.
- Technology Transformation: The imminent rollout of smart metering in the short to mid-term future will require vital investments in information technology for setting up turnkey projects for smart metering network and application infrastructure. It will be necessary to build up components like
- Mass deployment of smart meters
- Meter reading databases and applications
- Data warehouses and analytic tools & data migration programs
- Customer interfacing applications and portals
- Integration with existing systems
These components and underlying infrastructure will be critical success factors for generating maximum success from smart meter rollout programs. AMI implementation brings with it a transformation in the entire utility business process and impacts the entire span of utility operation & stakeholders. Hence validation of AMI implementation becomes a very crucial task. It becomes imperative that the utility validation partner in these kinds of programs understands the business domain, and ensures that the application not just conforms to the business requirements but is also able to meet other criteria (e.g., performance, data quality & security, application security).