This piece was originally published in the May 2016 issue of ei, the magazine of the electroindustry.
By Tim Wolf, Director of Marketing, Smart Grid Solutions, Itron Inc.
Over the past decade, utilities throughout the United States have been installing smart metering networks to automate the collection of energy and water usage data. Thus far, these smart meter networks have succeeded primarily in reducing costs, increasing efficiencies, and improving customer service. They have not yet provided a robust, intelligent technology platform to enable a broader array of applications to improve the safety, reliability, and efficiency of the power grid.
Greatly increased affordability of computing power for edge devices, coupled with significant advancements in software-defined communications and the evolution of standards-based network architecture, has redefined what is possible for many grid operations–use cases.
By combining these technology attributes in a unified platform, significant improvements in grid operations can be achieved, substantially increasing the return on investment for smart metering technology and network infrastructure. This includes using smart meters as advanced grid sensors to identify potentially unsafe grid conditions that until now have been very difficult to detect in either a practical or cost-effective way.
Stopping Hot Spots Cold
According to the Electrical Safety Foundation International (ESFI), home electrical fires account for an estimated 51,000 fires each year, nearly 500 deaths, more than 1,400 injuries, and $1.3 billion in property damage in the U.S. Specifically, arc faults are responsible for starting more than 28,000 home fires, killing and injuring hundreds of people, and causing over $700 million in property damage in the U.S. alone.
Electrical fires have numerous causes, most of which are beyond a utility’s ability to address. But what does keep utility personnel awake at night is the safety concerns associated with high-impedance connections (HICs) on their distribution networks. HICs or “hot spots” on the low-voltage distribution system or at the customer premise represent an ongoing safety risk and contributor to these statistics, while also causing customer voltage problems, equipment damage, and utility energy losses. An HIC is simply a poor electrical connection that can be created when splicing, tapping, or connecting wires; when foliage touches a line; or when a conductor or powerline fails.
When current is drawn through an HIC, heating occurs due to increased resistance, and voltage drops across the connection. As heating continues, the connection is further degraded, and this causes energy losses and the HIC to worsen over time. Symptoms start as voltage problems but can deteriorate to power outages and fires. Until now, there has been no practical way for utilities to identify and resolve these issues until they become more serious, with voltage problems, a downed conductor, or even a fire.
So how does this new generation of smart metering technology address this important safety issue? The combination of distributed computing power and new communications capabilities in meters and edge devices provides a practical and cost-effective solution for utilities to identify these losses, voltage anomalies, and potential safety issues before they become a safety hazard or a costly liability.
By continually analyzing high-resolution data about current flows and voltage in the local distribution system and communicating with neighboring meters through peer-to-peer communications to “compare notes,” this new generation of smart meters can continually and ubiquitously calculate and monitor impedance and quickly notify the utility of the presence and location of HICs.
This new generation of smart meters and grid edge devices are smart enough to know exactly where they are on the utility distribution system in relation to transformers, phases, feeders, and other devices. This location-awareness capability opens up an entirely new frontier of smart grid–use cases that were previously hobbled by the lack of a continually accurate connectivity model.
Is this technology a panacea for preventing electrical fires in the home or business? No, but by using a new generation of smart meters as intelligent grid sensors, capable of analyzing lots of data in real time at the edge of the network and taking action, utilities have a powerful new tool for addressing one safety issue that has not, thus far, been easy or cost-effective to solve.
Spotting Theft, Outages in Real Time
Hot-spot detection is just one use case related to grid and public safety. Power outages and theft of electricity have a significant financial impact on utilities, businesses, and consumers, representing hundreds of billions of dollars in lost revenue and economic productivity worldwide. Both also present safety challenges for utilities and the public. Electricity theft creates a dangerous environment for perpetrators, utility personnel, and the public alike, while power outages bring forth both direct and indirect public safety issues. So it’s in everyone’s interest to reduce energy theft and the frequency and duration of power outages.
Even with current smart metering technology, detecting energy theft can be an inefficient and laborious exercise of analyzing meter alarms and historical data from disparate systems and drawing inferences about where diversion may be taking place. With distributed intelligence added to the mix, diversion detection is now based on real time; continuous and localized analysis of changes in electricity current flows and voltage levels in the distribution network quickly distinguish legitimate metered loads from theft.
This results in a 300-percent increase in the accuracy and reliability of energy theft detection, meaning that utilities can dispatch field personnel more quickly and effectively to not only recover lost revenue but also quickly respond to potential safety hazards on their grid.
Like energy theft detection, the current state of outage detection with the smart metering network is still an inferential exercise based on how many affected meters can successfully transmit “last-gasp” outage messages over the network, how many of those reach the utility, and the filtering and analysis continues from there. This process is still hampered by lack of an accurate connectivity model that associates meters and distribution system assets.
By combining location awareness on the grid with peer-to-peer communications at the edge of the network, a new generation of smart meters systematically and continually evaluates the status of nearby meters and devices to quickly localize outage events and report reliable and actionable information back to the utility in near-real time. This includes the scale and location of the outage and affected meters and transformers, accelerating outage detection and analysis by 50 percent or more.
These are just some of the use cases now possible to improve grid efficiency, safety, and reliability with a next-generation distributed computing platform. With an open application environment, the platform drives energy management innovation from a broad ecosystem of technology providers. The potential of this platform, operating on a multi-application network, only increases as the smart grid and smart cities markets converge in this brave, new IoT world.
Mr. Wolf is responsible for marketing and communications for Itron’s global electricity and smart grid businesses. He is a regular presenter at industry conferences and writer in the industry trade press.