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Re: Typical last mile battery runtime (protecting against power cuts)


From: William Herrin <bill () herrin us>
Date: Fri, 3 Feb 2023 21:48:36 -0800

On Fri, Feb 3, 2023 at 9:36 PM Mark Tinka <mark@tinka.africa> wrote:
On 2/4/23 07:29, William Herrin wrote:
If it's just a little gasoline generator, 30 minutes is about right.
It takes 10 minutes to decide the power isn't coming back soon and
another 10 to drag the generator out of the shed, hook up the wires
and get it going even though it's cold, wet, and hasn't been run for
several months. That leaves 10 minutes to spare figuring out how to
convince the UPS that the generator power is good enough to retransfer
and stay.

Indeed - I was guessing given how reliable PG&E have been for Sabri, a
lot is probably pre-wired. I may be wrong.

Pre-wired makes it a standby generator, which 9 times out of 10 is
automatic start with an automatic transfer switch. It's running within
seconds whether you're home or not. Electricians cost too much and
20kva natural gas / propane generators with an ATS don't cost enough
more than the portables.

Compare:

https://www.costco.com/honeywell-18kw-home-standby-generator-with-transfer-switch.product.4000106705.html

and:

https://www.amazon.com/Honda-2200-Watt-120-Volt-Portable-Generator/dp/B079YF1HF6

understanding that an electrician will cost you $2000-$3000 for the
labor with any genset modification to the house wiring.


Regards,
Bill Herrin


-- 
For hire. https://bill.herrin.us/resume/


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