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Batteries are Cheap, Backup power is expensive

Dear Audiophiles,

To make a long story short I need to make sure my Internet devices stay on even when power is down for 24 hours, which on the South Carolina coast is realistic. 

I have an APC UPS 600VA which I though would do the job but it actually lasts less than 2 hours.  So I have been crunching the numbers and have really been surprised at how expensive an APC UPS is per minute of run time vs. modern battery based generators and DIY solutions. 

An APC UPS can be anywhere from $1.50 to $2.50 / minute of run time while an EcoFlow Delta for instance is around $0.50 to $0.75 / minute.  Not only is the EcoFlow cheaper but just has ten times better run times.  A single 1 kWh unit will keep my data closet running close to a full 24 hours.  I have too many devices in there which consume ~ 50 watts.  50 x 24 = 1,200 

I did in fact purchase a Delta 2 with back up battery for other reasons than the data closet, but when doing the research I also investigated DIY backup solutions and came across the idea of using a Renogy inverter/battery charger + 2x 12V LiFePO4 batteries.  It’s even cheaper than the Ecoflow but requires much more effort to set up.    I’ll do a full write-up on that soon. 

What have you done to back up your home devices?  

erik_squires
erik_squires OP
16,917 posts
 

@jwei - That's why propane generators are so attractive to me.  Even when you get an inverter type with sine wave output, their cost is modest and you can keep the fuel around for years outside if stored properly.  You also don't have to lug gas cans or the generator.  Just swap a tank in. 

goldenways
103 posts
 

For most home solar systems that are on the grid with no battery backup = zero power. The system shuts down automatically when power goes out. Power companies do not want their employees fried if there is solar power coming into their system.

goldenways
103 posts
 

Correction. 1st sentence should have included  "when the power goes out"

erik_squires OP
16,917 posts
 

@goldenways

To be clear:  My home generators are NOT energizing the household wiring or the electrical panel.  They energize my PCs and my networking gear, so I do not need to worry about a transfer switch. 

Any system which does energize the house wiring needs to have an adequate transfer switch / lockout mechanism.  There are two kinds I know of.  The very expensive automated kind that go with Solar and bckup generators like Kohler and Generac and there’s the medium expensive manual kind that prevent the service breaker AND the generator’s breakers from being closed at the same time.  

The idea with the "medium" expensive kind is the electrician puts a 50A inlet outside your home, where you can drag a gas/propane generator to and in emergencies fire it up.  The generator’s current can’t connect to your home until you’ve turned the service breaker off. Safe, but less convenient.  This type of switch is actually very cheap, except for the proper electrical installation of the breaker, the lockout system and installing the proper wiring and inlet to a convenient location. 

In the case of solar though I think it's even more elaborate than that, as you can sell power you aren't using, so there's some smart connection management happening there. 

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