Photo by AP Wideworld
Chattanooga utility installed 'smart' switches in power distribution system that can reroute power to live substations and pinpoint outages during extreme weather events. The system passed its first test during a storm in July.

Five days before Hurricane Sandy made landfall in southern New Jersey and punched a black hole in the power grid from Atlantic City to Long Island Sound's Connecticut shore towns, a high-powered group of utility executives convened a press conference in a well-lit auditorium at Con Ed's headquarters building off East 14 Street in New York City. They were gathered to roll out details of a $75-million smart-grid initiative. The top administrators from eight utilities serving New York state sat on the dais, along with the head of the New York Independent System Operator and the chairman of the state public service commission.

In his opening remarks, Con Ed Chairman Kevin Burke envisioned a stronger, more robust electrical grid with a "greater degree of reliability and sustainability than we have today." He surrendered the podium to Patricia A. Hoffman, assistant secretary for the U.S. Dept. of Energy's Office of Energy Delivery and Energy Reliability. Hoffman highlighted the program and placed it in the context of some $4.5 billion in federal stimulus funding for grid modernization.

In addition to other measures already moving forward nationwide under the 2009 American Recovery and Reinvestment Act, the New York utilities are deploying 39 phasor measurement units (PMUs) throughout the New York grid and placing capacitor banks at 234 sites across the state.

The high-tech upgrades, Hoffman said, "will give us situational awareness and better demand response, energy storage and advanced transmission technology" to improve the electrical transmission and distribution grid well beyond its current capabilities.

One by one, the utility executives summarized the their system improvements, detailing how the smart grid would improve reliability, ease energy distribution and transmission among different providers and energy sources, and possibly even cut costs for consumers.

The PMUs are integral components in a smart-grid system—supersensors capable of measuring system conditions as often as 60 times a second and relaying data to a supervisory control and data acquisition (SCADA) system. They give system operators automated, real-time feedback about load balancing as well as the ability to improve reliability by shedding load and rerouting power during disruptions. PMUs help operators manage wide area networks and shift power among providers to match supply and demand.

The capacitors are designed to improve efficiency by reducing losses during transmission over long distances. There is an 8% efficiency loss along transmission lines between generation and the consumer, says Garry A. Brown, chairman of the New York Public Service Commission. New York ISO predicts savings from the capacitors alone would be $7.6 million a year.

Stephen G. Whitley, president and CEO of the New York Independent System Operator, a FERC-controlled non-profit that manages transmission over 11,000 miles of high-voltage lines and monitors daily wholesale electricity sales, said the upgrades could have avoided the Aug. 14, 2003, blackout. That cascading event began with a First Energy transmission line outage in northeast Ohio and spread to adjacent systems along the Eastern Seaboard, quickly leaving 50 million customers without power. Federal post-blackout reports recommended a number of remedial actions, including expedited smart-grid development.

The stimulus package added momentum to the program. "We will have the tools to see that something is going on [and] take an action to stop it, which we didn't have before," Whitley said.

Paying Dividends

Smart-grid investment already has paid off for some. When a derecho—a broad, summertime, straight-lined, fast-moving squall line—roared through Chattanooga, Tenn.'s 600-sq-mile service area last July, the publicly owned utility EPB recorded nearly a quarter of its 170,000 customers had been knocked offline.

But the situation would have been much worse had the utility not begun to upgrade its system with $52 million worth of smart-grid tech, including software automation and 1,200 automated switches from S&C Electric Co., Chicago. S&C's IntelliRupter switches "can talk to each other," says Jim Glass, EPB manager of smart-grid development. Outages trip switches immediately up and down the line, redistributing power via alternative routes. The smart switches wirelessly report the outage location to a command center.

"We can immediately dispatch crews to a specific location to begin repairs," says Glass. "Before we added the new gear, 25% of our effort would be spent on sending scout teams out for visual inspections to find downed lines and pinpoint outages before sending out repair crews. Now the outages are already isolated." The upgraded system not only slashes the number of outages, he adds, it also minimizes the time required to restore power to customers.

EPB's improved distribution system is "smart …interactive and self-healing," says spokeswoman Danna Bailey. By analyzing data from smart meters and the SCADA system, the utility conducted a post-storm assessment. The results offered a dramatic validation of the spending: $1.4 million in operational savings and a 55% reduction in outage duration.

EPB's ability to quantify the financial benefits of smart-grid equipment should help investor-owned utilities make a business case to public service commissions for capital programs, says Mike Edmonds, vice president of strategic solutions at S&C. Publicly owned utilities such as those in Chattanooga and Napierville, Ill., already are "deriving benefits [from smart-grid investment], but many investor-owned utilities are unable or unwilling to commit," Edmonds says. In some cases, the failure is a utility's short-term strategy based on quarterly returns; in others, it's the recalcitrance of commissions to approve rate hikes.

Edmonds believes some smart-grid money could be spent more wisely. "Too much of the DOE stimulus grant money went toward AMI [advanced metering infrastructure]," he says. Unless the last segment of the electricity chain—distribution to the end-user—is configured smartly, with advanced switches and capacitors capable of self-healing in upset conditions, "then you don't really have a smart grid."

And even though at the fringes of Sandy's path utilities—such as PEPCO in the Washington, D.C., area—used high-tech controls to identify outages and restore power quickly, a smart grid is of minimal value when major chunks of the transmission and distribution infrastructure are taken out, Edmonds says.

David J. Manning, senior vice president with the New York office of engineering consultant Vanasse Hangen Brustlin Inc. and executive director of the New York Smart Grid Consortium, agrees but says utilities, even those now rebuilding in the devastated storm zone, will see smart-grid technology quickly pay for itself. "The drivers are reliability and cost," he says. "After Sandy, I think people will see it as reliability with a large R and cost with a small c."