Say one thing for the smart electric meters now being installed in smart grid pilot projects: They have become a cry to arms for consumers worried about data privacy, billing accuracy, radio frequency (RF) emissions exposure, and even safety. In fact, a few have built steel cages around their traditional electromechanical meters to keep utility personnel away from them: They don’t want their old meters swapped out for “smart meters” that will allow two-way data flow. According to newspaper reports, some Texans have gone as far as brandishing guns to run off utility workers.
An incident in the Vancouver area of Canada further fanned the flames of smart meter resistance when a house fire there broke out shortly after one of the meters was installed -- twice. The homeowner says 20 different electrical appliances and numerous electrical outlets were destroyed in the latest electrical fire and claims the smart meter is to blame. All this begs the question: Are such concerns justified?
Not according to two experts at the Electric Power Research Institute (EPRI), Brian Seal and Annabelle Lee.
“In my years of meter design and development, I’ve never known of a fire being traced to a solid-state digital smart meter,” says Seal. “The meter itself doesn’t generate any power, energy, or voltage and has a completely passive connection.”
In short, Seal explains, the typical residential meter has four wires attached to the back, 120-V Phase A and 120-V Phase B, which are connected to the utility and to the load. Ground bypasses the meter and does not connect to it. The meter itself — whether electromechanical or solid-state — connects to the household using four blades that plug into metal jaws in the socket on the exterior of the house.
“Where issues can arise is when a meter is pulled from a decades-old socket and a new meter is put on,” explains Seal. “In rare cases, some loosening or corrosion may exist in the socket, which could then weaken one or more of the blade-jaw connections. If the meter connection isn’t tight, the area can heat up, causing what we call a hot socket. This is related to the process of meter removal and replacement and is independent of whether the meter is smart or dumb. The remedy for this is to replace the defective part.”
Even if a hot socket arises, any damage should be confined to the socket and meter itself, thanks to stringent electrical codes that guide their design. That said, the sheer magnitude of smart meter deployment means that some hot sockets will likely arise. For example, in a typical year, 10,000 meters might be pulled and replaced among an installed base of a million. But with a smart meter swap-out, the whole population could be replaced in a single year, leading to a higher probability of hot socket issues.
Then there are the issues of billing accuracy and RF exposure from smart meters. Both concerns have been investigated by EPRI and other organizations. In a perfect world, says Seal, each investigation should not only resolve homeowner concerns, but also discover any product imperfections so that solid-state meter designs may be continually improved. When advanced metering functions are needed, going back to electromechanical meters is not an option.
EPRI says RF exposure from smart meter usage is basically a non-issue. EPRI has concluded that automatic meter reading power meters installed in homes produce RF levels much lower than FCC guidelines stipulate, even at close range.
Cyber security is another safety-related issue, though of a digital sort. Rather than physical safety, some consumers are concerned about invasion of privacy and who might access the detailed electrical usage data now being collected.
“A lot of work has been done over the past several years regarding grid security,” says Annabelle Lee, EPRI technical executive and cyber security expert. “Utilities and other organizations want to make sure all data is protected and not tampered with, to protect against potential attacks, ensure billing accuracy, and keep hackers out of the system.”
Lee explains that no personal information is stored at the meter itself. Electricity usage data is collected at different time intervals, encrypted, and sent wirelessly to the utility.
“Like banks and other financial institutions, utilities have many safeguards in place to protect data and consumer privacy. These methods are not publicly available, but involve sophisticated controls and cryptography. They are kept secret so the wrong people can’t gain access to how the systems work,” says Lee. “EPRI’s Cyber Security and Privacy program addresses the emerging threats to an interconnected electric system through a collaborative approach on cyber security standards, business processes, and technology to protect the electric grid. The program also will undertake research projects to assess technologies and controls on data privacy for the grid.”
Besides EPRI, multiple organizations are working on issues related to cyber security. In fact, a major component of DOE’s American Recovery and Reinvestment Act grants address this issue. NIST and several other organizations have created guidelines and documents addressing cyber security as well.
American Public Power Association, www.publicpower.org
Electric Power Research Institute, www.epri.com
National Association of Regulatory Utility Commissioners, www.naruc.org
National Institute of Standards and Technology, www.nist.gov
National Rural Electric Cooperative Association, www.nreca.org
Smart Grid — DOE website, www.smartgrid.gov