By Wim Kerstens, Eneco, and Xia Yang and Marco Janssen, UTInnovation
Smart metering, also referred to as advanced metering infrastructure (AMI), is one piece of the puzzle in developing smart grids. The change from automatic meter reading (AMR) to AMI means moving from one-way communication with meters to real-time, two-way communication. AMR is primarily focused on replacing manually read meter operations, while AMI includes not only AMR, but also promises a comprehensive, integrated collection of devices, networks, computer systems, protocols and organizational processes dedicated to distributing highly accurate information about customer electricity, gas, district heating and/or water usage throughout the utility and back to the customers.
In short, AMI solutions provide a built-in communication pathway to enable extensive smart grid functionality. The value of smart metering lies in the interconnectivity and data, which serves as a cornerstone for the smart grid.
Eneco, a Dutch utility, has performed an AMI case study for approximately 1.9 million electricity and 1.9 million gas meters. Eneco Grid Management has a number of customers for which they are the gas supplier but for which another grid owner provides the electricity, and also otherwise. This will create several interesting issues, regarding the implementation, the operations and the maintenance of smart metering.
Smart Metering Issues and Challenges
Smart metering offers many tangible benefits (see sidebar ” Smart Metering Drivers and Benefits”), so why aren’t more utilities going ahead with making a wholesale transition to smart metering? As shown in Figure 1, today’s utilities are beset by many issues, which continue to burden the market and hinder growth.
Many utilities do not want to be the first to implement smart metering because of the risk of higher R&D, implementation costs and maintenance costs. In fact, the risk of a higher total cost of ownership is the key issue. Another major challenge faced by manufacturers/vendors is the dynamic and immature market condition. Conservative regulators resist the higher initial cost of smart metering investments, doubting the promised benefits will materialize. Data management size and complexity is another deterrent. The need for massive databases and servers to manage the huge amounts of metering data is a perceived barrier. Other hurdles are variations in technology such as multiple open standards and ideas, as well as environmental concerns, aging workforces, low customer acceptance, and rising stakeholder expectations, etc.
It is a big challenge for utilities to implement smart metering in a feasible way. However, a modern utility should always be aware of and proactive about new technologies with a variety of investigations on the above-mentioned barriers/issues.
Implementation Strategies and Concerns
Reduced meter reading costs alone normally do not justify smart metering. The additional benefits such as improved system reliability, deferred construction and better customer service should be treated more favorably.
Utilities should have different strategies and incentives for different consumers as an integral part of a smart grid approach to achieve higher customer satisfaction levels than they achieve today.
Different market models may result in a non-homogenous meter infrastructure with different levels of functionality within grid areas. It is therefore necessary to provide for a certain level of standardization and interoperability of the smart meters installed.
One of the most important points is to create a good business case for different models and update it often to investigate the advantages and shortcomings for both utilities and customers. To build the smart metering business case, utilities should develop functional, technical and organizational requirement specifications, as well as make a proper cost/benefit assessment.
Eneco Business Case
Key to the Dutch market is that the deployment of smart metering is a requirement of the Dutch Ministry of Economic Affairs. This means that the Dutch utilities, including Eneco must act now. Eneco would have embarked on a smart metering project even without this requirement, but probably later and in a different way. At this time, however, there is a need for more investigations regarding the business case and profitability of such a project.
Eneco has identified several opportunities for a smart metering solution, including:
- More and better input for capacity calculations;
- Voltage quality improvement;
- Improvement of the fault compensation/restoration process;
- Possible support to resolve faults (decrease customer minutes lost); and,
- Future aspects regarding sustainability, which may also be influenced by political decisions regarding renewable and sustainable energy.
In the Netherlands, grid operators work together closely as a result of the Law on Independent Grid Operation (Wet Onafhankelijk Netbeheer). Utilities are working on a nationwide specification for smart meters which is expected to be finished in August 2008. Then, the grid owners will start the implementation of smart metering. The large-scale deployment was originally scheduled for 2009 but has been postponed for two years by the Dutch Ministry of Economic Affairs. Replacement of all meters should be finished within six years.
For all Dutch smart metering projects, the national developments will be of great importance. This includes the approval of the new Dutch specification NTA8130 by the European Union in Brussels, the new metering market model, and the decision of whether or not to introduce capacity-based rates.
The national standard is, from a protocol point of view, depicted in Figure 2 (pg. 30), in which:
- OSM stands for “other service provider.” The electricity meter has a P1 port (read only) to provide information to (for example) a display at customer’s premises.
- The P2 port, which can be either wired or wireless, will be used for “other meters” such as gas meter, thermal meter, water meter and for which the mbus protocol is foreseen to be used.
- The P3 port is the communication port to the central access server (CAS). The DLMS protocol will be used for the interface and the COSEM objects are standardized and approved by the DLMS User Association.
- In case of power line carrier (PLC) there is the need for a data concentrator (DC). The standardized protocol for communication between the DC and the CAS will be XML/web services. For the communication between the DC and the meter this will be DLMS with standardized COSEM Objects.
The objective of standardization is to have an interoperable and interchangeable AMI concept for the meter, communication technology and interface to the central access server. The CAS itself will be a part of the utility’s IT architecture, which should have the opportunity to provide, for example, a connection or data exchange with a DMS or asset data warehouse. But the main functionality for the CAS (obligation for the grid companies) is to facilitate the functionality for all retailers/suppliers, such as providing meter data, remote controlling, etc. The so-called P4 port should facilitate this.
Figure 3 (above) shows a part of the Dutch national specification and gives the total system overview.
Eneco has already installed roughly 50,000 smart meters used in an AMR system, but these meters do not yet fully comply with the new national specification. For the P3 port, currently GPRS is used, but pilots with PLC will also be done. For the P2 port, mostly wireless communication will be used, but wired communication will also be piloted. Eneco believes in hybrid solutions; there is not one best solution or technique.
Starting in early 2009, Eneco will install smart meters which are compliant with the new national specification, if available.
The Future of Smart Metering
The Eneco AMI case study demonstrates the feasibility of the smart metering implementation. After pilots are finished and analyzed, the national specification is finished, and the vendors have developed and tested the meters (so prices are known), information will be available about the costs and benefits. It also will be important to follow developments in the rest of Europe (for example, EdF France), the U.S. and the Far East because Eneco does not want meters (or functionality/software) that will only be used in the Netherlands since that will drive up prices.
The case study demonstrates the importance of good asset management for meters, because functionality can change rapidly. This also creates a need for remotely managed firmware upgrades. Also decreased life expectancy of the infrastructure and increase of disturbances, mainly caused by the telecommunication in relation to the more information provided by the meter, are important issues for AMI-related asset management.
The future of smart metering will depend on the policy and decisiveness of utilities as well as governmental bodies (regulators). Customer awareness, energy savings, increased security of supply and customer satisfaction will be main drivers for smart metering. By realizing a smart metering implementation that meets these objectives we are paving the way for smart grid development. To achieve the benefits of a smart grid, a smart meter, a smart utility, a smart government body and of course a smart customer are required.
Wim Kerstens is a senior specialist in asset management with Eneco. He has more than 28 years of utility experience with energy management systems, substation automation, asset management and information technology. He participates in the Eneco project for smart metering and is involved with the national specification for smart meters. He holds a MSc in Electrical Engineering.
Xia Yang is a consultant with UTInnovation for smart grid, advanced metering infrastructures, substation automation and power system protection. She holds a PhD in Electrical Engineering.
Marco C. Janssen is the president of UTInnovation. He has more than 18 years experience with protection, control, monitoring, power quality, advanced metering infrastructures, smart grid and substation automation. He is member of IEC TC57 WG 10, 17, 18, 19, the IEEE PES Power System Relaying Committee and CIGRE WG B5.32. He is the editor of the Quality Assurance Program for the Testing Subcommittee of the UCA International Users Group. He holds a BSc in Electrical Engineering.
Smart Metering Drivers and Benefits
The key drivers of smart metering are the functionality of the smart metering system, which provide many benefits for both utilities and customers, including the following:
Time-of-Use Metering: Customers can be billed based on their time of use; therefore, demand can be shifted from peak periods to off-peak periods, improving energy efficiency.
Remote Connect/Disconnect: Remote power connect/disconnect using a remote service switch will make system operations more efficient, provide customers more options for how they consume and pay for energy consumption, and will increase operating flexibility and reliability. It can support prepayment services, lessen the burden on utility personnel and improve employee field safety.
Remote Threshold Change: Remote threshold change can be used in case a shortage of electricity should be anticipated. It can also be used on an individual basis, in case the maximum current for a customer should be lowered, because of bad payment.
Customer Access to Information: Customers can view a variety of information through diverse methods, permitting those customers to make energy-efficient choices and to shift demand to off-peak periods.
Demand Response: Demand response can improve electric grid reliability, manage electricity costs, and provide systems that encourage load shifting or load shedding during times when the electric grid is near its capacity or electric power prices are high. It also can provide quicker and better information for when to use distributed renewable resources or where to use market-based rates to reduce peak demand.
Prepayment: Customers can prepay their accounts and read their current balance, and utilities can enforce disconnection when the prepayment balance reaches zero.
Theft Detection: Utilities are facing revenue losses due to energy theft. The smart metering system can be used to report when customers are stealing energy or tampering with their meters.
Outage Management: Outage management programs allow utilities to achieve faster and complete outage response, reducing customer downtime, lost revenues, and safety risk, which greatly increase operational efficiency. Smart metering systems provide an opportunity to automate processes in case customers have to receive financial compensation due to an outage longer than a defined period.
Network Optimization: Smart metering systems can be used to analyze the quality of electrical power by reporting harmonic data, RMS variations, voltage and VARs, and can communicate directly with distribution automation networks to improve power quality and fault recovery times.
Distributed Generation: Smart metering systems can be used to detect, measure, regulate and dispatch distributed generation by customers, which can help utilities manage the islanding issue related to the use of distributed generation in the system grid.
Third-Party Access: The smart metering system can be used to permit gas, district heating and water utilities, contract meter readers, aggregators and other third parties to read electrical meters, read gas, thermal and water meters, or control third-party equipment on customer premises.