Energize Weekly, March 17, 2021
Climate change – the heat waves, flooding, droughts, and hurricanes it may bring – poses a multibillion-dollar threat to the country’s aging electric grid, according to a report from the U.S. Government Accountability Office (GAO).
Without significant efforts to upgrade the grid and make it more resilient, the annual cost of outages could rise from the average between 2006 and 2019 of $55 million to $480 billion by the end of the century, the GAO said.
“Climate change is expected to affect all aspects of the electricity grid, from generation, transmission, and distribution to end-user demand,” the report said.
The stress created by a changing climate will be visited on the senescent electrical grid. The U.S. has more than 10,000 power plants and 642,000 miles of high voltage transmission lines. There are also 6.3 million miles of distribution lines.
Seventy percent of the grid’s transmission lines are at least 25 years old, and the average age of power plants is more than 30 years. Most of the nation’s transmission was built in the 1950s and 1960s, with an expected life of 50 years, according to the American Society of Civil Engineers.
The two federal agencies most directly involved with regulating the gird – the U.S. Department of Energy (DOE) and the Federal Energy Regulatory Commission (FERC) – need to make changes to address climate change and grid resiliency, according to the GAO.
“DOE identified climate change as a risk to energy infrastructure, including the grid, but it does not have an overall strategy to guide its efforts,” the report said.
As for FERC, it has not taken steps “to identify or assess climate change risks to the grid and, therefore, is not well positioned to determine the actions needed to enhance resilience.”
The stresses delivered to this aging infrastructure will be different in different parts of the country.
Changing rainfall patterns and droughts could hurt hydropower generation in Alaska and the Northwest. Coastal power plants in the Northeast face risks from rising oceans, storm surges and flooding. A warmer climate will increase the frequency and intensity of hurricanes. The Northern Great Plains grid could be jeopardized by wildfires.
Heat waves are a two-edged sword for at the same time they spark increased electricity demand, they reduce transmission efficiency. Warm temperatures in the Southwest are estimated to reduce transmission line capacity 1.5 percent to 2.5 percent, according to a DOE report.
“Higher temperatures cause the expansion of transmission line materials, and sagging lines can cause permanent damage to the lines, increasing the likelihood of power outages when the lines make contact with other lines, trees, or the ground,” the GAO report said.
Similarly, transmission capacity can be reduced and distribution lines damaged during increased wildfire activity.
Higher temperatures and heat waves could impact all regions of the country, decreasing the efficiency of electricity generation, particularly where plants depend upon rivers for cooling water, as well as reducing the efficiency of transmission and distribution systems.
“Climate change poses risks to the electricity grid—the power generation, transmission, and distribution system—that can potentially affect the nation’s economic and national security,” the report said.
Extreme weather events already have been the main contributor to an increased frequency and duration of power outages in the U.S.
For example, in February 2021, extreme cold weather from the Canadian border as far south as Texas resulted in record winter power demand and left about 4.5 million customers in Texas without power, along with about 376,000 customers in Louisiana and Oklahoma.
In July 2019, a heat wave in the Northeast led to two power outages that left more than 100,000 customers in New York City losing power. The outages also disrupted commercial activities, transportation systems and traffic-control operations.
In August 2017, Hurricane Harvey left more than 300,000 customers in Texas without power. The power outages affected critical infrastructure, such as hospitals, water and wastewater treatment plants, and refineries, which contributed to an increase in gasoline prices, both in the region and the nation.
Windy and dry conditions in California in 2019 increased the risk of wildfires and forced the shutoff of transmission as a public safety measure, affecting more than a million customers and leading to $2 billion in economic costs.
Utilities are already responding with investments to repair and make their grids more resilient, the report said
Hurricane Sandy, for example, interrupted power to eight million customers in the Northeast in 2012. Con Edison, the utility serving New York City, lost 10,000 utility poles, 900 transformers and five transmission substations.
The utility has spent $1 billion to repair the grid and make it more resilience, including floodwalls, submersible transformers and flood proofing at substations and generating stations.
The GAO report outlined some the actions DOE and the FERC could take to promote grid resilience.
“DOE can provide financial assistance to further its mission and goals in the form of formula and competitive grants, cooperative agreements, and prizes,” the report said. “DOE officials told us that they plan to release a funding opportunity announcement in fiscal year 2021 to support energy resilience initiatives.”
FERC could take action leading to an updating of the reliability standards set by the North American Electric Reliability Corp. The commission could also take steps to determine whether statutory changes are needed in the Federal Power Act to adequately address climate change.