Zythryn wrote: ↑
Tue Nov 12, 2019 8:56 am
From what I recall, one of the primary things not being done was clearing trees from lines and poles.
In Minnesota the local utilities do any cutting/trimming of tree branches that are interfering with the lines or local transformers.
tweets examples of damage found during inspections before re-energizing power lines after a PSPS.
Here are some examples:
I found this report filed w/the CPUC after the PSPS that affected me: https://www.cpuc.ca.gov/uploadedFiles/C ... Report.pdf
. Page 93 (Appendix D) has some example pics of damage.
The topic of why not putting more power lines underground has come up but the issue is cost.
https://www.usatoday.com/story/news/nat ... 946935002/
https://www.sfgate.com/bayarea/article/ ... 503808.php
It costs about $3 million per mile to convert underground electric distribution lines from overhead, while the cost to build a mile of new overhead line is less than a third of that, at approximately $800,000 per mile, according to a section on PG&E's website called Facts About Undergrounding Power Lines.
California has 25,526 miles of higher voltage transmission lines, and 239,557 miles of distribution lines, two-thirds of which are overhead, according to CPUC. Less than 100 miles per year are transitioned underground, meaning it would take more than 1,000 years to underground all the lines at the current rate.
$15,000 for every PG&E customer?
PG&E, the state's largest utility, maintains approximately 81,000 miles of overhead distribution lines and approximately 26,000 miles of underground distribution lines. It also has about 18,000 miles of larger transmission lines, the majority of which are overhead lines.
At a cost of $3 million per mile, undergrounding 81,000 miles of distribution lines would cost $243 billion. PG&E has 16 million customers; distributing that expense equally would amount to a bill of more than $15,000 per account.
As a 2017 San Francisco Chronicle story notes, it costs about $1.16 million per mile to install underground distribution lines. In cities, that number is much higher; work in San Jose cost $4.6 million per mile. Overhead lines cost about $448,800 per mile in comparison.
Most of the higher costs are associated with digging trenches for the lines. There is also the cost of repaving roads and other environmental factors, such as flooding or earthquakes.