Why your cell phone is silent: FCC says 874 sites are down in California. They lack backup power

From the article:

A report prepared by the Federal Communications Commission reveals that at least 874 of the state’s cell sites were out on Monday, up from 630 on Sunday, when fires broke out all around the Bay Area.

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In addition, more than 454,722 subscribers with landline phones, cable television or Internet also lost service due to power shutoffs, according to the FCC report.

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Residents said even their once-reliable landlines and Internet, such as those operated by Frontier Communications, weren’t working. Comcast/Xfinity also was down. Four FM radio stations — K238AF, KKLJ, KNOB, KSXY — reported being out of service. Also silent were two AM radio stations, KIHH and KYAA.

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In the era of traditional phone service, Ma Bell’s lines were themselves energized and very reliable.

But companies’ transition to Voice over Internet Protocol (VOIP) – with phone calls over the Internet – is dependent on outside electricity. VOIP calls fail when either the company’s facility or the resident’s home lacks backup power.