Setting up a lower power emergency back up

[ScottR]

I am looking for an emergency back up system to help with periodic outages from wildfires and earthquakes (th joy of California).
I'm considering the Bluetti AC50CS or the EB150.
I'm not sure if the EB150 is overkill given that I only need to be able to run the igniter on a gas powered water heater, a 12V portable camping fridge, the igniter on a gas powered furnace, and recharge cells phones and laptops (not at the same time). If I want to try to keep the freezer going, I assume I'll need the large capacity battery.
I was also thinking of using a 100W panel-I'm gravitating toward a Rockpals SP003 (for the portability) or an HQST panel (for the price).

Does this make sense? Any suggestions?

Also, if I'm storing a lithium battery for an extended period time between uses, what level of charge should be used?
Thanks

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[McCarthy]

For a price between those 2 battery packs you can get a proper and quiet 2800 watt generator. Mine feeds right into the entire house after disconnecting the grid. Runs all lights, the large fridge / freezer in the kitchen, computers and monitors, network and internet, chargers, and an emergency AC unit for the bed room. Unlike your 100 watt panel, this doesn't run out of juice that quickly. I can siphon gas from my 3 cars and go for over a month.

 

[Deleted-User]

Alternatively, a propane generator significantly relieves the need for 'fresh' fuel, and many already have a few propane tanks for their grills. The popular Honda eu2200i has a propane add-on kit available (as do others), or purchase a 'dual-fuel' version.

 

[Supervstech]

I built my own solar generator from 60Ah cells... 16S and a 1500W inverter.
Powers everything all day when power drops out... 100W panel would take weeks to recharge though... I use 3...

 

[Hedges]

a 12V portable camping fridge, ... If I want to try to keep the freezer going, I assume I'll need the large capacity battery.
I was also thinking of using a 100W panel-

Also, if I'm storing a lithium battery for an extended period time between uses, what level of charge should be used?

That fridge has a compressor, I hope? (not thermoelctric)

You need to figure out how many Wh/day it consumes.

Home freezer/fridge could be 1500 Wh/day, look up consumer energy label.
It has a starting surge for motor, probably 2000W for fraction of a second, which inverter needs to deliver.

Summer time in my San Jose area, figure 5.5 hours effective sun so 400W panel making 350W actual, maybe 300W AC after inefficiency, could deliver 1500 Wh or so per day.

Pay attention to maximum wattage input for PV, as that may limit attaching enough for what you want to do. It will be enough to recharge the battery, but maybe not enough to run inverter at 100% or even 50% load for 8 hours while the sun shines.

Best way to deal with refrigerators is use a timer so they run while the sun shines and PV is generated, then shut off at night leaving battery for other loads.

Lithium batteries like to be stored part full, maybe 50%. Specific products' documentation or others of same chemistry would give a better figure.
Data sheet in this link says 20% to 40%

Is BIG BATTERY full of Crap??

Good day; I almost hate to wade in here as this has been an interesting conversation. But for me: My 280ah batteries for my RV have a 14w heater on each side for a total of 28 watt consumption. The testing I did last spring showed that the heaters could increase the temperature of the battery...

diysolarforum.com

 

[rin67630]

I am looking for an emergency back up system to help with periodic outages from wildfires and earthquakes (th joy of California).

Expect the sky to be deeply darkened in case of wildfire your battery will not feed you very long. You will probably not be happy with this idea.