Wednesday, December 12, 2012

Can Hurricane Sandy Shed Light on Curbing Power Outages?

Marianne Lavelle
For National Geographic News
Published November 2, 2012
As Hurricane Sandy churned north and west over the Atlantic Ocean on its inexorable collision course with the U.S. East Coast, miles-long convoys of bucket trucks, aka cherry pickers, were already rumbling over interstate highways toward the anticipated strike zone, from as far away as Alabama and Texas.
It was well understood that the superstorm's harm would reach far beyond whatever wreckage it left in its path. Sandy's impact would spread far, wide, and quickly through the electric power grid—a vital lifeline that underpins every aspect of modern life, but one that is easily severed by falling trees and saltwater. Even before the storm hit, East Coast utilities summoned bucket trucks and work crews from the South and West, so they would be on hand to help repair downed power lines.
"It is virtually impossible to protect the system from a storm like Sandy," said Clark Gellings, a fellow at the industry's Electric Power Research Institute. Instead, he said, the industry focuses on a more achievable goal: "Can we do a better job at putting it all back together?"
By one measure, they did: Bucket-truck brigades enabled utilities to rapidly restore electricity to a large share of the 8.5 million homes and businesses in 16 states that lost power at the height of the storm.
Yet as of Friday morning, there were still nearly 3 million customers in New Jersey and New York without power, and 700,000 more in 11 states from Massachusetts to Virginia and as far west as Michigan.  New Yorkers were crowding Manhattan coffee shops to cop electric charges for their cell phones. New Jerseyites queued with red canisters outside gas stations to get fuel for their home generators—but gas was short too, in part because there was no electricity to power the pumps . Consolidated Edison, the New York utility that was dealing with the largest disruption in its history, was hoping to get the lights back on in Lower Manhattan by Saturday. That was a revised goal, after New York Governor Andrew Cuomo declared Con Ed's original timetable of two weeks "unacceptable."
On Thursday, as the U.S. Air Force began airlifting more utility trucks from California to New York, others too were questioning whether the bucket-brigade strategy was good enough. Many energy industry experts were viewing Sandy as a wake-up call: proof of the need for massive investment to make the electric power grid more resilient against such a disaster. Massoud Amin, director of the Technological Leadership Institute at the University of Minnesota and a pioneer in grid research, notes that the East Coast power infrastructure is among the oldest in the nation. "That aging infrastructure is a marvel of 20th-century engineering," he said. "The question is how do we upgrade it for the 21st century?" 
Large Blessings, Small Margins
The electric system could count some successes in the wake of Sandy. Thirty-four nuclear power plants—one-third of the U.S. total—lay in the massive hurricane's path, and there were no meltdowns or other disasters.  The hurricane's landfall at Atlantic City was just 40 miles south of the nation's oldest nuclear power plant, Oyster Creek Generating Station; although the plant was offline for refueling, loss of power and flooding was a concern because of the need to keep the radioactive nuclear fuel from overheating. Oyster Creek shares the same design as Japan's Fukushima Daiichi plant, which suffered a catastrophic meltdown after the earthquake and tsunami in March 2011. 
At Oyster Creek that didn't happen. The plant declared an "alert" for 36 hours when winds and heavy rains generated tides 6.8 feet above mean sea level at its water intake on the Forked River. But the water never rose high enough to impact the operation of plant equipment. When the electricity from the New Jersey grid went out, two locomotive-sized backup diesel generators started automatically and continued to power the crucial pumps that circulate cooling fluid through the reactor and the pool where spent fuel rods are stored. Cooling systems also continued to function at all three other nuclear reactors that experienced shutdowns—Indian Point and Nine Mile Point in New York, and Salem in New Jersey.
"This isn't the first time our plants have been through conditions like this," said Tom Kauffman of the Nuclear Energy Institute, an industry group. "We practice regularly and are continuously prepared."
Earlier this year, however, the U.S. Nuclear Regulatory Commission ordered the industry to reassess both its flooding and seismic risks, in light of the Fukushima accident. David Lochbaum, director of the nuclear safety project for the Union of Concerned Scientists, said Sandy underscores the wisdom of that decision.
"The Fukushima plant wasn't of appreciably lower quality or poorly constructed compared to the U.S. plants," Lochbaum said. "It was given a much more severe challenge. None of our reactors would have survived that either." If the water had risen another 21 inches at Oyster Creek, the plant's service pumps might have been submerged, according to NRC spokesman Neil Sheehan. That would have increased the risk of a loss-of-coolant disaster, although the plant had a back-up pump and the option of hosing the spent fuel with fire suppression system. In any case, it would be days until the cooling water would have been lost through evaporation.
Winds Versus Floods
In New York too, Hurricane Sandy drove home the point that the old benchmarks of risk might no longer apply. In one of the most dramatic videos captured the night the storm hit, a fireball burst over Manhattan's East Village when saltwater surged into one of Con Ed's substations. (Watch video below:)New York had never seen floodwaters higher than the 11-foot storm surge triggered by a hurricane in 1821. Con Ed had designed underground equipment at its voltage switching station to withstand a storm surge of 12.5 feet. But Sandy's waters reached 14 feet, flooding all of Lower Manhattan—and blowing up the substation. "Water and electricity don't mix, especially if you put salt in the water," said Gellings of EPRI.
Con Ed operates the world's largest underground electric distribution system, serving more than 3.3 million customers in New York City and neighboring Westchester County; more than 86 percent of its system is buried, including 94,000 miles of electric cables. Yet Sandy knocked out service to more than 900,000 of its customers.
Often, after storms that down overhead lines and cause widespread blackouts, public criticism of electric power companies centers around their resistance to making the investment in burying lines and other infrastructure to keep it safe from the wind. The damage that Sandy did to Con Ed proves that burying the systems is no fail-safe. To restore service, the utility is now pumping massive amounts of water out of the facilities, cleaning seawater from components, and drying, repairing, replacing, and inspecting equipment.
Though saltwater can be as damaging as wind, it may in the long run be easier to protect against. "You can make watertight compartments for the stuff that's underground," said Jeffrey Dagle, chief electrical engineer at the U.S. Department of Energy's Pacific Northwest National Laboratory. "It's all a matter of money." To make such investments, utilities in the United States would need to gain approval from state regulators whose job is to keep unnecessary costs from being passed along to customers. But Sandy might change the perception of what's necessary. "The process of managing risk is informed by past events," said Dagle. "If something has never happened before, it's hard to convince regulators to fund a project to prevent it from happening. If Con Ed went to the regulators next week, it might be a different story."
Smart as Well as Tough
But many industry observers stress the electric power system needs more than stronger defenses—it needs to be smarter. "Smart meters," touted for their ability to help consumers monitor and curb their energy use, also allow utilities to pinpoint accurately where outages occur and respond quickly.
"Many people don't realize this, but not too long ago, the only way a utility knew there was an outage was if a customer called," said Gary Racliffe of ABB, a major supplier of smart-grid equipment to utilities in North America and elsewhere. An industry survey done last May found that one third of U.S. households, 36 million in all, have had smart meters installed. Unfortunately none were in the service areas of the major New York or New Jersey utilities. Smart meters are expected to be in half of all American homes by 2015.
But utilities will probably invest even more heavily in the coming years on smart systems to automate and modernize the distribution of electricity. One example is "self-healing" systems that can automatically detect a fault on the grid—say, when a tree falls on a power line—interrupt and isolate that fault within milliseconds, then reroute the power to an adjacent feeder line. While homes adjacent to the downed tree might have no power until the crew comes to remove it, most of the customers on the line have their power restored within minutes.
Amin argues that the U.S. power industry, in partnership with the government, should be making an investment of about $30 billion a year over the next 20 years to upgrade distribution systems. (Con Ed has been using $136 million in federal stimulus money for that purpose.) Not only would new technology make power systems more resilient to storms, but it also would make them more efficient and more able to integrate energy from renewable sources such as the wind and the sun. Smart-grid technology, Amin estimates, could reduce the costs of outages by about $49 billion per year, and by reducing energy use, save customers $20.4 billion a year. "The costs of upgrading are far below the benefits we get," he said. 
Like everyone else, Amin marveled at the reports of far-flung utility crews headed to the East Coast to help respond to Hurricane Sandy. "My hat goes off to them," he said. "But we can lessen the stress on them if we deploy a public-private partnership to make a smarter, stronger, more resilient grid and infrastructure. Not only can we do this, I am convinced we must do this. Secure and reliable operation of these networks is fundamental to national and international economy, security, and quality of life." 

No comments: