Winter still wreaking havoc on Tahoe power grid
By Kathryn Reed
Power outages are normal, but this hasn’t been a normal summer.
Liberty Utilities is still dealing with the aftermath of last year’s winter. Relying on NV Energy is also impacting customers.
Liberty provides electric service to the California side of the Lake Tahoe Basin, as well as to Truckee, Alpine County and other regional locations. Liberty has been doing so since 2011 when its parent company bought NV’s California territory.
Normally the top four reasons for outages are:
· Car vs. pole accidents
· Weather, such as snow, wind, lightning, or trees falling on wires
· Critters (like squirrels) getting into equipment
· Equipment failure.
This summer has been different.
“Unfortunately, we’re still feeling the impact of the extreme weather experienced this last winter which really stressed the infrastructure (poles, wires, transformers, etc.) with snow loads and lots and lots of water in equipment (such as underground vaults) that had never been exposed to that much water/snow before,” Travis Johnson, Liberty’s vice president of electric operations, told Lake Tahoe News. “Many of these weak points aren’t readily visible, so the crews can’t proactively go out and fix; they have to wait until a circuit goes out and then track the problem down.”
Liberty is also at the mercy of NV Energy. When something goes wrong across the state line, it can have a ripple effect. An example of this was on Aug. 28 when NV Energy’s Round Hill substation had a fire and cut the power to customers in Nevada and California. The substation is still out of service.
“Liberty has picked up additional load to help them continue to serve their customers until this substation can be repaired. Picking up this load causes greater circuit exposure to the elements because the lines are switched in a way that makes them longer – for example there is more opportunity to have a lightning strike or car v. pole – and being in fire mode means we have to send someone out to patrol the line before we can restore service,” Johnson said. “The same is true for NV Energy customers—carrying additional, temporary load for Liberty results in greater exposure for their customers.”
Johnson pointed out that while the companies are separate in so many ways, they are relying on a lot of the same old equipment. They have interties to send electricity between service areas. That’s why outages can affect both states at the same time.
Much like the agreements between the local water districts where they can help the other if need be, Liberty and NV have a similar mutual aid agreement.
Outages are usually short-lived. When it’s not fire season the lines automatically recharge. It’s still fire season, so when the energy stops flowing on a line crews have to go find it. It isn’t like there is some circuit board in some office pointing to where the problem is, or that a flick of switch can solve it. It takes manpower out in the field to resolve the problem.
