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PG&E Undergrounding

I have a Saturday afternoon show on KPFN and recently I was discussing operational and infrastructure improvements PG&E, its lax Public Utilities Commission regulators, and blind watchdogs from the state Legislature should consider implementing prior to the electrical monopoly being let off the hook to resume business as usual.

One of those improvements dealt with undergrounding its overhead wires in high fire risk areas. I wasn’t speaking of PG&E undergrounding its entire 100,000 plus miles of overhead distribution lines, only those in high fire risk areas. By the way, PG&E claims it would take 1,000 years to bury all of its overhead lines, something I don’t believe anyone is demanding they do.

Anyway, a listener sent me the following email:

“My friend, an engineer from the Bay Area, was here last week when we were listening to your show when you were talking about PG&E … He emailed this article from an engineering organization he belongs to. It’s about putting electric lines underground.”

Here are excerpts from “Improving the Grid Could Prevent Fires” published in the Engineering News-Record.

“After the latest distressing round of California wildfires and blackouts, more needs to be done to improve, not just rebuild, the aged power grid now recognized as causing some of the fires. Fixing the fragile system has been on the infrastructure to-do list for years. The rising Western wildfire threat is the newest problem to rise to the top. A system rebuild must avoid simply restoring it to status quo.

“In our view, any upgrades must create ‘cornerstones’ for a system that includes hardened infrastructure, buried lines and distributed generation … Using better materials, such as high-temperature, low-sag conductors—line sag led to the 2003 Northeast blackout—also helps.

“Targeted line undergrounding, based on life-cycle costs, has been applied strategically, most notably by San Diego’s utility, which is converting 15 miles of overhead lines a year, and by Duke Energy in the eastern states it serves. Utility customers are usually all for undergrounding, which has been long studied. But there are trade-offs. When buried lines fail or sustain damage, it takes longer and costs more to detect faults and restore service.

“Most of the time, however, installation costs are the real crusher … Pacific Gas & Electric, the bankrupt utility whose lines are believed to have touched off several recent wildfires, has done some undergrounding conversions via a state public service commission rule that spells out whether ratepayers or developers pick up the costs. Per mile, PG&E reports, its cost to convert overhead to underground distribution lines is $3 million. New overhead lines cost only $800,000 per mile. PG&E faces added problems because it serves urban and rural parts of the state. Of 107,000 miles of distribution line, only 26,000 are underground.

“In the long run, distributed generation makes much more sense. In the event of a disaster, power producers can be switched to local mode and disconnected from the grid, so they would not be affected by an outage. Also, a small local grid would be easier to maintain because it would not have long, high-voltage transmission lines running through areas with a lot of vegetation … We need practical leadership to change course in the midst of the emergencies created by the aged system we now have.”

Some things to note about undergrounding.

PG&E estimates seem inflated. It wasn’t that long ago that PG&E undergrounding cost approximately $1 million per mile, compared to $500,000 overhead. The Edison Electric Institute is an association that represents all U.S. investor-owned electric companies. Its cost estimates vary, based on different voltages, to convert overhead to underground distribution lines—ranging from $158,000 to $1.9 million per mile, about evenly split between labor and materials. So PG&E’s estimate is about $1 million more than the highest estimate of the Institute’s.

It’s generally agreed that repairing underground lines may take 2-to 3 weeks, while overhead repairs take a maximum of 48 hours.

I think the engineers have some good ideas that definitely need to be explored by the PUC, Legislature, and Governor before they make any more hasty decisions burdening PG&E ratepayers with a generational bailout of a bankrupt utility that has proven beyond any doubt that it is not to be trusted.

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