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?
OP I have a Renogy 1000 with 2x car sealed battery. I live in California so there are not much power outages but if the city power blew up the tranny during hot months, well there it is. I manually switch over my router, switches and Wi-Fi over to the Renogy and some lights and Fan. It works for about 6 hours straight for me experience with today's tech, see how a Solar panel can charge your batteries and if large enough, power up your home data center |
@joeycastillo - I lived in California a long time. The power may not go out but it's not always right... :D That's kind of what I'm talking about, but in my case I'm going to leave the inverter in 24/7. Inverter is sized at 500W, and I'll use 50W. Batteries will stay on a charger 24/7. No transfer times. At most in an emergency when my Ecoflow isn't working or doing other duties It may draw 110W. I'm starting off cheap. I had a 500W inverter for the car/emergencies already. It was $70 or something. I'm going to try it out for now and see how it goes. If I win the lottery or something I'll consider something significantly larger. By my calculations, with 2x 100Ah batteries I should get about 40 hours of run time for Internet alone. |
I now understand how you're planning to wire this setup of yours. I think it will work. Mine is more manual. I use the Inverter when I want to be standalone. Then after nearly draining the battery, I then connect the batteries to a charger to fully charge it back. So, in your case, you want 24x7 power from the Inverter. in that case, you need a Charger sized to keep the battery "charge" at the same time feeding your devices. you need to research how to determine this power rating necessary to accomplish this. or crudely, i will attach an amp meter between the battery and inverter when you have all your devices plug in and determine the amps drawn. then choose charger based on that. (give it some headroom) |
@joeycastillo For the sake of simplicity and cost I think in case of a long term outage I’ll manually enable the inverter. I just tried the inverter I already have and it’s a lot noisier than I expected, even at idle. For now, I think I’ll go with leaving a smart charger on the batteries to keep them topped off and if we ever have a real outage I’ll hook up the inverter as needed. Perhaps a future me who is wealthy and can do all the other home upgrades he needs will provide an inverter upgrade. |
@dinov +1 Same here. I think it is a Cumings natural gas generator with 50A/120V = 6kW. For brownouts and the 5–10s between power out to generator auto-on, a few small APS do the job. OP @erik_squires : Re UPCs, also consider battery degradation. At work I had a couple of Desktop PC-size UPCs (120 and 240V) to protect our scanning electron microscope mainly from brownouts. Batteries need to be replaced every 5-10 years. For one they cost, and in one case the batteries ballooned and I had to cut the case to get the batteries out. Between installation and full failure, the battery performance degrades, so if you really want to make sure your back-up lasts for the desired time, also factor in lowered battery capacity with time, or schedule regular battery swaps. |
