By Joseph Turgeon
Smart grid – specifically advanced metering infrastructure (AMI) – investments in electric utilities have rapidly expanded over the past several years. As the technology has matured and electric utilities have gained experience, the anticipated benefits from these investments are becoming more proven. Electric utilities have expanded the use of the AMI network applications from meter reading to remote connect-disconnect, voltage monitoring, transformer monitoring, capacitor bank automation and others. Based on this evolving maturity, gas and water utilities are looking at AMI technology opportunities to provide a foundation for their own “smart infrastructure” systems. This article will explore the adaption of AMI within the gas and water utility industry, and introduces some of the advanced capabilities that may lie ahead.
Much of the North American gas and water automated meter reading (AMR) implementations remain walk-by/ drive-by technologies which predominantly employ one-way communications technologies. The 4Q12 Scott Report estimates 61.1 million gas AMR modules and 55.7 million water AMR modules have been shipped in the North American market. Of those, approximately 11.5 million gas modules and 7.9 million water modules have been deployed in fixed network configurations. It appears that the majority of these modules are one-way with less that 10% supporting two-way capability. To understand the total market potential, ABS Energy Research reported in 2009 that there is an addressable available market of 81.8 million gas customers and 94.1 million water customers in North America. That same year, ABS Energy Research reported that globally there were 389 million gas and 767 million water utility customers. Two-way AMI is in the early adaptor phase of market penetration in gas and water; thus, the opportunity is financially significant for the entire segment.
The earliest adaptors of fixed network AMR technology were multi-utility customers of Landis+Gyr’s Cellnet one-way AMR radio frequency (RF) technology. The 4Q12 Scott Report estimated that approximately 3.8 million Cellnet one-way gas modules have been shipped to such companies as AmerenUE, Puget Sound Energy, We Energies and a number of other electric-gas and gas utilities throughout the United States. The major standalone one-way AMR fixed network early adaptor has been Pacific Gas & Electric, which has deployed approximately 4.3 million Aclara STAR RF modules on gas meters. On the water front, cities such as New York (with 970,000 water meters), Washington DC (with 150,000 water meters) and Boston (with 90,000 water meters) are using Aclara’s one-way Star RF network.
The recent round of AMI initiatives has been concentrated in multi-utilities deploying two-way fixed network gas AMI in conjunction with electric AMI, and either deploying gas AMI modules concurrently or as a follow-on. Since the AMI network is already in place, and service calls are being made to customer premises to install electric meters, the incremental costs of adding gas modules is relatively small in the scheme of the entire project. Three examples of such projects are San Diego Gas & Electric (SDG&E), which is using Itron’s OpenWay AMI with ZigBee gas modules communicating with electric meters; CPS Energy based in San Antonio, Texas, the largest municipally owned electric-gas utility in the US, which is using Silver Springs Network’s AMI mesh network with gas modules communicating to the electric meter; and NV Energy along with Sask Energy in Saskatchewan, Canada, which are planning to use Sensus FlexNet tower-based AMI technology.
Southern California Gas’s $1.2 billion, 5.7 million meter AMI project using Aclara’s two-way STAR RF technology – which started module installation in late 2012 – is the first major standalone gas fixed network deployment in North America. On the water side, Sensus is making good progress selling its FlexNet tower-based AMI system to small- and mid-sized municipalities; to date, Sensus has over 300 municipal customers including such customers as Albuquerque, New Mexico and Arlington, Texas, each with over 100,000 water customers.
As the batteries of the first generation gas and water AMR modules expire in walk-by/drive-by systems, many of these devices are being replaced with two-way communicating devices. For example, this has been the case for Itron customers replacing 40G with 100G series gas modules. However, these two-way modules are not usually accompanied by a ubiquitous fixed network investment to provide complete service territory coverage for AMI network capabilities. Often a small fixed network capability is deployed in high density/high usage areas such as an industrial park. Thus, the limitations of these “non-networked” solutions remain – that is, a field operator still has to be in close proximity to the gas or water meter to communicate with it. These meters remain logistically constrained to once per month data collection as part of the monthly billing read process. Without a networked architecture to access end point data, it remains challenging to fully realize the two-way time synchronized communications potential of real time hourly, or daily, or ondemand meter reads, and AMI module tamper alarms.
ADDING VALUE TO AMI
Because meter reading efficiency at most utilities has already been greatly improved with the initial investments in walk-by/ drive-by and fixed network AMR systems, the business case to upgrade to a two-way AMI fixed network for simple or on-cycle, monthly billing is difficult to justify. Added value has to be derived through enhanced operational efficiencies when investing in an AMI network.
However, the more promising opportunity for investing in the underlying AMI infrastructure may not be derived from the smart meters themselves. Indeed, the ability to deploy more sophisticated devices and sensors in the gas and water distribution system can provide a significant opportunity to improve utility operations in real time, mainly through reducing or eliminating truck rolls, but also by introducing business intelligence and analytics across the organization.
To date, the greatest technical challenge facing gas and water smart infrastructure applications is that they utilize battery powered devices. Power either does not exist in the locations where the water or gas module resides, is prohibitively expensive to provision, or is not prudent from a safety or security perspective. While great strides have been made in lithium battery technology, frugality of power budget over the life of the device is the overarching design criteria to support 20-year battery life cycles. Minimization of computational capacity and RF transceiver operations is imperative and requires clever design approaches. Thus, most water and gas AMI programs remain focused on meter reading applications because the benefits are well understood, the computational burden on battery power is minimal, and the required transmissions for simple meter reading are limited to a couple of times a day.
However, recent AMI adaptation in gas and water is leveraging developments used by peers in the electric sector for communications, cybersecurity, data privacy, and smart grid, and adapting them for applications such as theft detection, leak detection, load balancing, demand response, and distribution automation. On the customer service side of the business case equation, beneficial examples may include hourly or daily interval data for web presentment to improve customer engagement and consumption education; communication of usage patterns to enhance conservation; influence and enforcing conservation objectives; and satisfying regulatory requirements.
Today, several manufacturers are developing various advanced devices and applications for a smart gas and water infrastructure, such as remotely actuated valves for residential applications to address leak, theft, and non-pay situations. However, remote reconnect is still major issue in the gas application, due to pilot relight requirements.
One of the newer concepts gaining interest in the gas utility market in the wake of the San Bruno, California and Allentown, Philadelphia incidents is focused on pipeline safety and regulatory requirements. This application automates galvanic and impressed current cathodic protection (CP) applications using time-stamped AMI communications to meet US Department of Transportation PHMSA 192 requirements for bimonthly and annual pipe corrosion surveys. Using the AMI network for measurement and reporting eliminates the need for manual data collection and enables a stronger focus on problem prevention and correction. Advanced AMI based CP is applicable to water utility infrastructure applications as well.
An equally interesting automation application for both gas and water is to use AMI communications devices combined with pressure sensors on mains, distribution lines, and service lines. Much like going to the doctor, this ability to report high and low pressure status across the network provides deeper understanding and insights to the overall health of the distribution system, and particularly stresses on an aging infrastructure. AMI offers the opportunity to implement more and lower cost monitoring points than a typical supervisory control and data acquisition (SCADA) network.
Additional concepts being investigated for gas specific applications include using sensors for methane detection, and mercaptin (odour) measurement and reporting. For water utilities, measuring water delivery temperature at the residence and chemical composition measurement for chlorine, lead, and other particulates are also important. In all cases, these applications focus on taking cost out of operations through communications efficiencies by better using utility technicians to solve problems and not merely “read routes or gather data”. The benefit that is more difficult to monetize benefit is improved customer service.
APPLICATIONS FOR AMI DATA
Many of AMI benefits are based in a significant increase in operational data available from smarter devices in more real time. AMI smart applications turn basic measurement data into actionable information to improve utility operations, customer service levels, preventive and predictive maintenance, safety, and regulatory requirements. The question remains: How to do it for gas and water utilities? Simply automating CP reads not only eliminates truck rolls, but also allows the information to be sampled on a more granular basis, in real time, and stored in databases in a manner easily transformed into regulatory reporting formats. Analyzing time synchronized hourly usage across all customers can help a utility’s engineering, distribution control, and operations departments understand their residential and small customer usage patterns more intimately. This insight will become increasingly more important to gas utilities as natural gas becomes a greater fuel of choice for home heating, industrial applications, and power generation as a cleaner energy source than coal and oil.
For water utilities, data intimacy insights will gain value as water becomes a scarcer resource. When time synchronized meter information is correlated between master meters and consumers and coupled with AMI enabled acoustic leak detection devices, utilities will be able to more accurately inventory daily and hourly levels. This can lead to better localization of potential leak and theft areas, and provide input to more accurate loss calculations within integrity management programs. Taken together, this will allow the water utility to source and treat less potable water, reducing overall costs to both the utility and the customer, an important factor to municipalities that have to purchase their water.
Combining granular end-user consumption information with enhanced pressure sensing will enable a utility to better understand load and delivery dynamics across its distribution system. This is especially important for gas utilities to meet residential demand on very cold days when commercial/industrial curtailment events are common.
Finally, further enhanced capabilities are evolving from the meters themselves. Several meter manufacturers are now offering solid state gas and water meters using a variety of ultrasonic and magnetic flow measurement technologies. Since these technologies require battery power just like the AMI communications modules, it will not be long before these functions become tightly bundled to combine advanced communications and enhanced functionality in a single package. Bundling may even spur an industry drive to standards-based open interfaces between devices and communications modules which in turn may open the market to solution providers and further innovation.
Deploying smart infrastructure will be transformational to the way a distribution utility does business in the future. However, smart gas and water infrastructure will more likely be an evolutionary development over the coming decade rather than a revolutionary change over a couple of years as our electric utility counterparts have encountered.