It's been widely reported that to mitigate the risk of power lines sparking wild-fires in California, Pacific Gas and Electric (PG&E), the largest utility in California, has been preemptively de-energizing power lines that run through fire-prone areas. This article from the LA Times gives a figure of 850,000 customers expected to lose power over the weekend.
However, an op-ed on the Epoch Times posits that there may be an alternate reason for the power cuts (emphasis added):
By 2018, the state’s renewable portfolio had jumped to 43.8 percent of total generation, with wind and solar now accounting for 17.9 percent of total generation. That’s a lot of power to depend on from inherently unreliable sources. Thus, it would not be at all surprising to learn that PG&E didn’t stop delivering power out of fear of starting fires, but because it knew it wouldn’t have power to deliver once high winds shut down all those wind turbines.
The background explained in the article is that above a certain wind speed, wind turbines are shut down because they can no longer be controlled to the correct speed for electric generation (this is referred to as the cut-out speed).