Within the decade, analysts predict that hurricanes will be more frequent or intense, and that above-average-strength storms will occur on average six times a year when traditionally they occurred twice. Acreage destroyed by wildfires has already nearly doubled since the early 1990s. The boundaries of “tornado alley” are moving further east, to more populous areas. Rising average temperatures put more electric infrastructure at risk of malfunctioning or operating less efficiently during periods of spiking demand. More people are living in areas more prone to flooding.
These realities, laid out by reports such as the Fourth National Climate Assessment from 2018, aren’t the most extreme of the doomsday scenarios, but make a case for why and how utilities can adapt their systems for the near- and long-term likelihood of extreme weather.
Potential Costs
Utility adaptation strategies have costs to implement, and costs associated with inaction.
In a 2019 report, Why, and how, utilities should start to manage climate-change risk, McKinsey and Company estimate that the cost of damage and lost revenue for large southeastern utilities will rise by 23% as a result of increasingly extreme weather. In the long term, the report lays out the case for investing in prevention and creating resilience, such as through “strengthening the grid, exploring investments in batteries and microgrids, and working with new partners,” which it posits will be a significantly less expensive strategy for utilities and the communities they serve.
Recovery costs and challenges following extreme weather events have already increased as critical pieces of the electric system become vulnerable. For example, 44 power plants were in flooded areas during Hurricane Irene and 69 during Hurricane Sandy.
The McKinsey report extrapolated that the average economic damage for each Southeastern investor-owned utility would be $1.7 billion by 2050, compared to an estimated cost of $700 million to $1 billion to prepare for impacts related to climate change.
“While each utility’s cost-benefit calculation will differ based on its unique risk exposure profile and infrastructure costs, our conclusion is that it pays to prepare for extreme weather,” the McKinsey report concluded. “There are also likely to be ancillary benefits, such as improved reliability and enhanced diversity of supply.”
Adjusting Strategy
The two utilities are about 2,500 miles apart, and their climate, customer base, and systems are very different, but Seattle City Light in Washington state and Riviera Utilities in the southern tip of Alabama are, like other public power utilities, finding solutions to make their systems more resilient, such as hardening assets, decentralizing generation, and creating microgrids.
For James Wallace, chief operating officer at Riviera, the effort to protect the utility against hurricanes and other storms along the gulf coast and make the system more resilient has been a priority for the utility for about two decades.
“We’ve just had to adjust,” he said, as he described the weather that has swept through the region. “Hurricane Sally in 2020, for instance, really wiped out the county and about a month later Hurricane Zeta came along and glanced us. Sally devastated our system. There was no damage to us from Zeta, but it created severe problems for an investor-owned utility 30 miles to the west of us, where we sent crews to help.”
He said severe hurricanes seem to be more frequent, and afternoon thunderstorms, with severe lightning and potential wind damage, pop up much more often.
“Day-to-day weather is just different,” he said. “We had temperatures below freezing around Christmas. That isn’t normal. People here aren’t used to having to insulate their pipes.”
At Seattle City Light, Rhonda Strauch, climate change research and adaptation advisor, is focused on a different set of concerns. Diminishing snow melt and runoff reduces the hydroelectric generation that the public power utility depends on for nearly 90% of its power. It also must deal with more and larger forest fires (and their often-related mudslides) along with temperatures shifting from the region’s steady norm, which can even damage inner-city underground lines, a new problem for the utility.
“We see this as central to our mission now,” she said. “In 2015, we developed a plan with strategies for handling the range of problems related to climate change, but we were experiencing impacts at that very same time and have since,” she said, noting that they are updating the plan to create an “information hub” that can be an evolving source of information about changing concerns and efforts to mitigate them.
Understanding Risk
A federal report entitled Climate Change and the Electricity Sector: Guide for Climate Change Resilience Planning provides a step-by-step toolkit for assessing vulnerabilities and tackling the potential damage from natural disasters. “Vulnerabilities and feasible solutions vary widely by utility, component, system, region, and geography,” that report said. “Actions taken to improve resilience today, even as a part of routine planning and maintenance, could deliver significant benefits to all users of electricity both now and in the future.”
The guide stresses the importance of utilities fully understanding the scope of potential risks and system vulnerabilities before diving into which specific resilience measures to take. Measures can range from hardening strategies, such as reinforcing structures to restoring surrounding wetlands, to outright relocation of assets, and operational modifications, such as enhanced vegetation management and demand response programs. Fully understanding the utility’s unique risk profile helps to make smarter investments, as utilities can better screen out risks for which the available resilience measures seem unlikely to provide benefits that outweigh costs, the report stated.
“Planning for climate change will enable utilities to anticipate stressors both on the demand side as well as increasingly frequent and severe weather-related challenges,” said Chris Gillespie, a senior consultant at Energetics and contributor to the report. “With appropriate planning, utilities can both improve performance on reliability metrics and reduce long-term costs to their ratepayers.”
Taking Action
Riviera has been working on creating resiliency on a number of fronts – from stepping up the tree trimming cycles to every three years to installing underground distribution lines for new developments. Approximately one-third of the distribution system is underground, and that number grows each year, Wallace said.
“We’ve created redundancy and protection wherever we can,” he said. “Each substation transformer is set up to handle feed from another substation transformer. We can shift load to another feeder or substation with minimal impact to our customers.”
He noted that the distribution system is operated at a 15-kilovolt level but is insulated at 27kV to protect against lightning and unintentional contact. The utility also uses automatic transfer schemes that ensure service is maintained to critical loads such as hospitals and water treatment facilities.
Poles rated to handle 100-mile-per-hour winds are now used, well above the standard that calls for 60-mile-per-hour wind resistance in the region.
“Reducing outages is a priority for us and I think creating this sort of resiliency is important to improve your utility — and it’s something customers want,” said Wallace. “Every utility should always be looking for ways to improve. This is a new challenge we should be prepared to face.”
When Seattle City Light surveyed its customer base about climate change, it got 4,500 replies, with 94% of respondents saying they were concerned about the issue and 87% of them saying they were “very concerned.” The utility serves about 130 square miles, including all of the city of Seattle and several adjacent communities within King County.
“It is an issue we are conscious of and working on because we are facing these challenges every day — but it is also something our customers are keenly aware of,” Strauch said. That concern prompted the utility to review and update its 20-year plan. The process relies heavily on researchers and the experience and knowledge of other utilities, she said.
“We share information with others from our experience and gain new perspectives from all the research being done and the experience of others who face these challenges,” she said.
Most fundamentally, perhaps, lower amounts of snowfall have created less runoff for the utility’s hydroelectric plants along the five different rivers and for the Bonneville Power Administration, which provides about half of Seattle City Light power. Meanwhile, temperatures have been making more dramatic shifts in the region, previously known for more consistency.
The utility has turned to cooperative arrangements through the California Independent System Operator to supplement its supply and is adding wind and solar generation. It is also experimenting with microgrids through pilot projects and looking for ways to generate power from other sources closer to smaller clusters of users.
Microgrids are the focus of several public power utilities, including the Virgin Islands Water and Power Authority, which is developing an 18-megawatt battery storage system for a portion of the island of St. Croix. In Chattanooga, where seven tornados touched down in the region last April, and their frequency has increased, an $18 million solar and battery microgrid system has been developed using city and federal funds. It will provide consistent power for police and emergency services.
Forest fires — and landslides which often result from them along with more intense, drenching rains — are an increasing problem in the Pacific Northwest, Strauch said. She noted that the utility has buried more distribution lines or replaced them with lines that will break away so that if there is a landslide, there isn’t a cascading effect.
In remote areas, the utility also has replaced roofing material that could catch fire, installed more poles that are made from a composite material that is less likely to burn, and used more concrete pipe that can withstand fires and mudslides.
“We’re always looking for ways to protect those vulnerable systems.” She noted the utility has even installed WiFi-connected devices that can detect smoke in remote areas.
Strauch stressed that the utility has focused on assessment of the climate trends and utility vulnerabilities and planning for ways to create resiliency. She said they actively seek information from reliable partners and funds from the federal government. One grant proposal may support the hardening of transmission lines that bring about 20% of the power into Seattle.
The breadth and shifting of the problems and potential solutions make such an “organic” approach valuable to even smaller utilities, she suggested.
She believes utilities should:
- Collaborate – with policy makers and government officials, industry groups and researchers.
- Access information – from an increasing range of research.
- Educate – staff about the concerns and strategies and get buy-in.
- Take action – including public information and “on the ground” throughout the system.
“Everyone is facing extremes and you can prepare but also learn from them as you respond and develop solutions,” added Strauch. “What did you do and how can you keep the system working the next time a similar event occurs?”
