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

PS - My bad.  The Renogy unit I quoted above does NOT include a charger.  I’m rethinking that.  It seems they did have an inverter/charger but not sure if it’s discontinued. 

Unfortunately fossil fuel power is not a great option.  The data closet is furthest away from the outdoors.   I am absolutely in love with the idea of propane powered generators though, the ability to store propane for years is appealing, so long as you can store it away from the main building, which I cannot.   Same of course for gasoline.  I have no separate shed/garage in which storage of those would be safe.   

So overall the solution for me has to fit in the bedroom closet.  

Also would love, in a perfect world where I can afford to buy an ugly ass stainless steel truck an outdoor generator.  The yearly maintenance costs alone are more than my budget. :)  Also, no access to natural gas.  This is an electric only neighborhood. 

Many pickup trucks have 120 V outlets.  Just need to add a switch on your house electrical box to flip your source to a cable from the truck.  Turn on the truck before your APC UPS runs out of juice.  (Assuming you have the truck.)

@jwei You bring up a good point.  In 2021 the Great Texas Freeze prompted a run on Ford F-150 trucks for just such a reason.  It seems they feature from 2kW to 7.2kW inverters depending on the model.  Dealers were encouraged to loan them out, I’m sure generating a lot of goodwill.  

Few things wrong with this though.  First, I have a Toyota SUV with a wimpy 120W outlet.  About enough to run a laptop charger.  I did price out putting a 2 kW inverter along with the necessary upgraded inverter, wiring and extra battery needed.  About $1,500 installed I think.  Not a bad option, but about $1,000 more than I want to spend right now.

As for a UPS... too short of a run time  and too long of a charge time.  The EcoFlow battery generators however have terrific charging speeds on 120V.  Anywhere from 1,200 W to 1,800 W of power draw allowing them to recharge fully from 1 to 2 hours.  

In my home what MUST run is about 100W.  I’m not including the fridge or an electric blanket.   At that rate with just my Delta 2 + Battery I’d be out in a day, so pulling them out to the car, or running an extension cord and charging them every day would not be entirely unreasonable. 

I think my final solution is going to be 2 x LiFePO4 batteries with a 500W inverter and battery charger.  Final cost is around $500 for 2 kWh.  This will be in addition to the 2kWh capacity I have in the Ecoflow units.  Of course, if power is out longer than that I’m screwed, and none of this will save my refrigerated food or keep my AC running.  I think I’ll be able to manage a pot of coffee in the morning though. 

@billpete  - Sorry I missed your post earlier.   Personally, an outdoor generator like a Generac or Kohler is out of my budget for now... but, assuming it was not they still have a 10-20 second transfer delay.  I would still need a very small UPS for my networking gear and PCs to ensure uninterrupted usage, such as being on a video call. 

You are on the right track though, having out outdoor generator would greatly diminish the size of UPS or battery back up I need indoors.  At that point, practically any UPS would be big enough to handle my data closet.