Ice Storm Damage Feb

Utilities Take Action to Tackle Risks and Damages from Natural Disasters

Feb. 7, 2020
Methods focus as much on prevention as on mitigation.

With the sudden and precarious increase in natural disasters that we are seeing today, these disasters — even if they are infrequent, sporadic or one-time — have truly become forces to be dealt with. Hurricane Harvey, which hit the Gulf Coast of the United States in October 2017, was so relentless (it made five landfalls and raged for two weeks) and so costly (US$125 billion) that forecasters have retired “Harvey” as a storm name forever. But it should not take a disaster of that magnitude to spur utilities, cities and citizens into action.

Wildfires, storms and flooding have become more frequent, and the pressing question is this: how can communities prepare for the inevitable? Doing so can no longer focus simply on response and mitigation, it should include prevention. 

Today, utilities are responding to the challenge. Let us take a look. 

Utilities are still in the early stages of developing systems for near-real-time alerts and warnings for their customers. For its part, Consolidated Edison (Con Ed), which serves more than 9 million people in New York City and Westchester County, New York, began deploying 9,000 battery-powered natural gas detectors on its smart meter network in 2018. With the natural gas detectors, Con Edison is able to detect leaks and quickly alert its emergency crews to improve safety for everyone in the communities they serve.

With the severity and frequency of storms, floods and fires increasing precipitously, a real-time communications network that reaches all devices is no longer an option but a critical need.   

And utility customers are ready. Just as they can get continuous alerts about the shipping status of a product they have ordered online, they expect the same heightened level of responsiveness from utilities. The 2019 Itron Resourcefulness Insights Report found that 69% of utility executives and 55% of consumers are more worried about a disaster hitting them today than they were five years ago.

Solutions

Utilities are also taking proactive measures to harden their systems and thus prevent damages from natural occurrences. 

For example, utilities are using line sensors to spot momentary faults that might be caused by a tree branch or other vegetation brushing against the power line. And they are looking for repeat patterns — which spell trouble and imminent failure. With that data, they can initiate a truck roll to investigate the trouble spot. With sensors alerting on these potential risks, crews can then clear vegetation away from power lines or transformers.  

San Diego Gas & Electric has even taken longer-lasting and more durable measures. The utility, in tandem with the City of San Diego, has removed approximately 20 miles of power lines from San Diego neighborhoods. The partners plan to move underground about 100 miles of utility lines by 2022.

In a recent survey, 68% of respondents identified failing overhead equipment as the number one cause of pole fires on their systems, according to T&D World. “Specifics included insulator flashover, current tracking across insulators, and the effects on aging wood poles as the current leakage finds its path to ground.”

“The most comprehensive — and most expensive — solution is to move power lines underground where trees, wind, ice, snow, and most animals cannot touch wires, and where power-line failures can’t readily start fires,” said Gregg Edeson, an industry consultant, in a story in the San Francisco Chronicle.

Utilities in Florida are taking measures to replace wooden poles rated to withstand winds of up to 50-65 miles per hour with concrete poles rated for winds of up to 200 miles per hour.

Still, other utilities are innovating with moisture-detection sensors, allowing them to remotely sense areas where trees or other vegetation are becoming dry and brittle, creating a higher risk of fires. Moisture-detection technology is at the center of Colombia’s wildfire modeling efforts, which were highlighted in December 2019 at a meeting of the American Geophysical Union in San Francisco.

Updating the Grid

Another strategic move by utilities is to sectionalize their grids to reduce the scope of power outages, whether they are from storms, flooding or fires. They do this by using switches or reclosers to reroute the flow of power.  

Here’s why that’s important: a utility may have a power plant feeding power in one direction, and a power plant on the other side of the city feeding power in another direction. The utility can lay out the grid in such a way as to switch the flow of power in a different direction and restore power, minimizing the number of customers affected.

“Since last year, PG&E has installed about 160 sectionalizing devices to allow outages or faults in one area to be isolated, even as adjoining areas can be restored with power from other circuits,” said one industry watcher in an October 2019 story.

Commonwealth Edison (ComEd) is another innovator in this form of grid improvements. The utility has sectionalized its entire grid, to the point that even a major windstorm could bring power down to as few as 500 to 700 customers.

“The system is now automatically sectionalized. When there is a problem in the system, it isolates the problem and prevents the outage from spreading. So about 40% as many customers were affected in November as were impacted by the similar ice storm 20 years ago,” said ComEd CEO Joe Dominguez in a recent Q&A feature in Crain’s Chicago Business.

One of the advancements that utilities are making — and “designing” into their grids — is becoming proficient in all the domains that play into creating an efficient and durable grid. For example, utilities are becoming land experts and weather experts, and ultimately getting a better understanding of the risks and dangers to their grids. That’s a good sign and a true advancement.

A 2018 report from Itron revealed that barely over half — 57% — of utility executives felt their utility was either very or extremely prepared to recover from natural disasters. But with the frequency and severity of natural disasters increasing, utilities will have to do better. With the Bahamas still recovering from Hurricane Dorian, intense tornadoes wreaking havoc throughout the Midwest and unprecedented damage from wildfires in Australia and California, we need to prepare rapidly for what is just over the horizon.

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