Wildland Fires & our PUD Electric System
Fire Safey or "One-Shot" Mode
Have you ever heard the term “One-Shot”? It is a crucial operating mode that the PUD uses to help prevent wildland fires in our county.
Each summer our line crews and system operators complete the process of placing most of our distribution breakers and reclosers on “One-Shot” or “Non-Reclose” mode to help prevent fires due to faults on our system. The term one-shot or non-reclose means we reduce the number of times our reclosers operate from three to one. Because there is a chance that sparks are created each time a fault occurs on a line, reducing the number of operations reduces the chance of fire.
For example, when a fault occurs such as a tree falling into a line, the breaker, which is a safety mechanism, shuts the power off. In normal operations, the breaker waits for a fixed amount of time and turns the power back on. If the tree is still in the line, the breaker shuts the power off again, waits the fixed amount of time, and turns back on. If the tree is still there on the third attempt, it is considered a permanent fault and the power remains off. At this point, we will call out a line crew to remove the tree and restore power to our customers.
A fault could also occur when a limb falls into the line. The same operation happens, except that there is a strong possibility that the limb falls off of the line after the first fault. In normal operations, power would remain on after the second attempt because the breaker no longer detected a fault and customers would only see a very short (several second) power outage. In one-shot mode, however, the power stays off after the first fault to decrease the chance that additional sparks may be created by turning the power back on. The result is that power outages are more likely, but the threat of wildland fire is reduced.
Managing Trees & Brush
We have an in-house tree crew that follows a vegetation management cycle in an effort to keep trees and brush away from power lines throughout our service territory. For more on this topic and how you can help, please visit: Right Tree, Right Place & Tree Safety
Strengthening Our System
We work to strengthen our power system and mitigate fire risk by investing in upgraded equipment. Most recently we are working to change out our hydraulic reclosers and replace them with electronic reclosers. This allows for better monitoring and coordination of the system.