Protecting the entire power grid from outages by rainproofing 1% of power lines

Simulations suggest that storm sheltering just 1% of the power lines in a power grid can reduce the likelihood of a hurricane-induced power outage by a factor of five to one in 20. The demonstration, conducted on a mock version of the Texas power grid, could help improve the resiliency of power transmission systems around the world.

“The importance of different power lines to the overall system becomes clear only when studying the partial disruption of the power grid as the storm progresses,” he says. frank hellman at the Potsdam Institute for Climate Impact Research, Germany.

To identify the critical power lines most in need of protection, Hellman and his colleagues investigated how the power grid responds to widespread damage over time. They focused on the large-scale “failure cascade” that occurs after the initial storm damage. When power plants and transmission lines shut down to protect against further damage, secondary power outages can occur and increase the impact of a hurricane.

Researchers have determined that wind-related storm damage, such as damaged pylons and fallen tree limbs from gusts, and resulting damage to Texas during seven historic hurricanes between 2003 and 2020. simulated both a series of power outages that occurred on the power grid.

Rather than trying to predict individual power line failures, which can be caused by fallen trees or lightning strikes, researchers set each power line's probability of failure based on local wind speeds during each storm event. assigned. Their model maintains the same 20 critical transmission lines, where initial storm damage can cause a series of secondary line failures, even if they randomly vary the probability of failure for each line and rerun the simulation. Consistently identified electrical wires.

This experiment synthetic network model of the Texas Grid, which was previously developed by a team at Texas A&M University. It is not an exact replica of the actual physical grid, but represents the overall behavior of the grid. “None of the power lines in that grid are real power lines,” he says. adam burchfield at Texas A&M University. “Therefore, to see if these results hold true for the real Texas grid, we need to perform the study on at least a model of the real Texas grid.”

Power grid operators themselves can run this simulation with their own detailed power grid models, although independent researchers typically do not have access to such models for security reasons. Once you identify which specific lines are weak points, you can weatherize critical components of your grid.

Beyond Texas, such simulations can also model grids in other locations where similar storms have occurred. It says it “may provide an opportunity to validate the model and results.” Chuan Yi Ji from Georgia Tech in Atlanta was not involved in the study.

Hellman acknowledges that wind damage models have limitations. It does not take into account the possibility of further damage from flooding or how precautions grid operators can take to prevent power outages.

Still, Burchfield said the study's use of “different scenarios” to check the probability of outages in a realistic grid model further emphasized the study's main findings. “I think grid strengthening is a key element in making the grid more resilient,” he says. “And this paper shows that strategically choosing which transmission lines to strengthen is important to have the greatest impact on resiliency.”