Hurricanes are one of nature’s most destructive forces. North America’s hurricane season runs from June 1 to November 30, peaking between August and September, and 2022 would be the seventh consecutive year of above-average hurricane activity, if predictions are correct.
A typical Atlantic hurricane season has 14 named storms, seven hurricanes and three major hurricanes, according to National Hurricane Center. The National Oceanic and Atmospheric Administration (NOAA) plans a 65% chance that the 2022 hurricane season will be above average, with 25% chance of near normal activity and only a 10% chance of below normal tropical cyclone numbers.
NOAA also tracks “billion dollar storms,” and these are increasing in frequency and intensity. Although the United States has yet to experience devastating hurricanes this season, we have already seen the impact of heat waves, wildfires and flooding, which have negatively affected many communities that are not fully prepared for these extreme weather conditions. As we look to a future distorted by climate change, planning for unforeseen weather emergencies has become an increasingly important requirement for utilities and the communities they serve.
With growing unpredictability and a general trend towards more frequent storms, more emphasis needs to be placed on preparing networks for extreme weather conditions to avoid causing widespread and long-lasting power outages. Utilities that are not well prepared for hurricanes and other weather emergencies run the risk of leaving customers in the dark, unhappy, unsafe and with significant disruption to their daily lives.
How hurricanes and extreme weather events affect the network
Hurricanes, heat waves, and other weather events can severely affect utilities and their ability to provide consistent, reliable power. Hurricanes in particular produce heavier rains and stronger winds due to climate change, and their impact on power grids increases accordingly.
The potential for hurricane damage is well known; power lines can be displaced or destroyed by high winds and falling trees, while substations and other facilities can be submerged by flooding. We are also seeing an overall increase in temperatures across the world and more frequent heat waves, which are driving unforeseen demand for air conditioning, refrigeration and other essential services.
This puts power grids under increasing pressure, increasing the risk of weather-related outages. Extreme hot and cold temperatures, such as the deep freeze from Storm Uri in Texas and this year’s heat waves in the United States, can compromise grid reliability and resilience. While these challenges cannot be entirely avoided, steps can be taken to mitigate their consequences.
Building a More Resilient and Sustainable Network: Planning and Preparation
Utilities can take a variety of steps to strengthen grid systems and make them more robust and resilient. Many of these preparations can be made in advance to allow utilities to respond more effectively in the event of a thunderstorm.
The first step in modernizing the network is to develop a solid recovery or preparedness plan tailored to the needs of each utility. It is essential that electrical equipment in substations can be returned to service as quickly and safely as possible, whether an outage is planned or not.
Utilities must also engage proactively in risk mitigation, an important aspect of which is vegetation management – downed trees or fallen branches account for a substantial percentage of outages. Today, utilities can use satellite imagery, drone imagery, and other aerial and still imagery, coupled with artificial intelligence (AI) to proactively monitor their infrastructure to identify the risk of outages. caused by poorly managed vegetation. This process can improve network performance during storms by “hardening” transmission and distribution circuits to mitigate storm-related outages. This approach can also reduce routine operating and maintenance costs, an added benefit.
For coastal utilities or those located in inland floodplains, erratic weather patterns have increased the need to protect substations from flooding. This may include the construction of dams, walls, distributed and/or elevated relay panels and the elevation of transformers, control houses and other major substation components well above the level of flood.
Substations can be raised using gas-insulated substation (GIS) technology. Additionally, pre-positioning modular equipment that can be deployed quickly to support major systems in the event of a disaster, such as modular mobile substations, can significantly reduce the time required to replace inoperative equipment damaged by major disruptive events ( compared to a previous average of 18 months to as little as seven days).
Building a more resilient and sustainable network: introducing new technologies
There are a variety of new and emerging technologies that can enable utilities to mount a more effective response to storms.
Data analysis has an increasingly important role to play. AI applications, for example, can help predict the anticipated impact of an expected storm by matching the characteristics of upcoming weather patterns to those of previous storms and analyzing the types of damage caused to the network in these cases. .
These apps can analyze the type of damage caused by previous storms, the locations of that damage, and the resources needed in terms of maintenance crews and equipment. Armed with this information, utilities can preemptively organize resources to facilitate a faster response.
One of the key steps in this process is moving to implementing a “self-healing” smart grid that uses smart metering and field sensor information to quickly identify, isolate and restore power outages. Utilities can make wider use of smart devices such as reclosers and distribution automation switches, to clean, isolate, and make a feeder return connection to reactivate the isolated, undamaged section of the feeder of a smart meter. On a loop start with a normally open connection point, this process can be completed in 100 milliseconds.
Smart meters can determine the extent of a fault and identify the protective device (circuit breaker, recloser or fuse) that was used to isolate the fault that triggered the fault, and ultimately clear that fault. This process is especially useful when a utility does not have a field network and smart sensors or communications-enabled smart devices. Many utilities are still evaluating the role of Advanced Metering Infrastructure (AMI) communications for operations, but interest is accelerating.
Utilities can also invest in developing a proactive Asset Lifecycle Management (ALM) process to identify equipment that represents a potential point of failure and therefore needs to be upgraded or replaced with more resilient components. . This approach can help harden the network to make it better able to maintain operations in the event of extreme weather events.
Deploying more robust energy storage systems, especially when combined with microgrid technology, can provide backup power in the event of a local outage. This is particularly important for critical loads, such as hospitals and similar public infrastructure, and also applies to remote communities or towns that experience frequent interruptions to their grid connections.
Overall, building a more resilient network can reduce operating costs, which translates into significant savings in money and energy. The reduction in operating and maintenance expenses associated with storm response is a major benefit for utilities, particularly if rate-based capital investments can improve storm resistance and resilience.
Endure extreme weather conditions on the road
Given the seven-year trend of increased hurricane activity, it is virtually certain that extreme weather events will become more frequent and more damaging. With the move towards electrification in many sectors of the economy (transportation, mining, steel production, construction, etc.), electrical infrastructure will be even more critical in the future.
As an industry, utilities must make every effort to harden the network, strengthen automation and operational systems to detect and mitigate disruptions. They should also plan ahead, pre-positioning equipment and crews where possible to help ensure rapid restoration of service when the time comes.
Utilities need to review plans for network upgrades and equipment replacements in light of the new reality of more frequent and devastating disruptions. This means they may need to proactively replace critical systems to ensure their network is operating at peak performance. The key to success will be critical assessment, careful planning and proactive measures to ensure that the infrastructure in place is as robust as possible.
—Antoine Allard is EVP, Head of North America, for Hitachi Energy.