Hmmm…it’s Generator Day here at Zeropolis. Drag the EU2000 out of its protective Hardigg case, set it up, run some high-draw appliance off it for a while to make sure eveything gets a workout, clean it up, and then back to storage for another month or two until the next Generator Day. The more I think about it, the more I think that this is going to be the year I finally get the stupid battery power supply done. It’s a remarkably simple plan brought to ruin by my unparalleled laziness. See, when the power goes out I have, really, only four power needs:
- Freezer/refrigerator
- Communications – running scanners, radios, internet, computer, etc.
- Security – surveillance and associated systems
- Lighting – It’d be nice to be able to not walk into the furniture
Now, except for the fridge/freezer issue, which is where the generator comes in, all the rest of that stuff can quite happily run on a DC battery supply.
The laptop runs on DC, as does the radios, scanners, and router. Same for the surveillance system. And the emergency LED lighting runs on DC as well. And since there is no need to have an inverter to turn the DC into AC, there isn’t the usual loss of energy accompanies such things. In short, if everything runs on DC I get more bang for my electrical buck than if I tried to run it on AC.
Ideally, what I’d like to set up is something where the batteries charge as needed off the house current, and when that fails they charge (albeit at a slower rate) off a couple of strategically placed solar panels. I then run the wires into a room where I plan on keeping all the critical systems. It doesn’t have to be a huge system…it just has to be big enough to run some fairly low-draw DC stuff for three or four days without a recharge.
Last time we had an outage here it lasted quite a while. I rather liked having cable TV and internet while the rest of the neighborhood was dark.
I run an Inergy Kodiak with a few deep cycle batteries chained off of it. The Kodiak is a 1kwh lithium unit and has a built in 1.5kw ac inverter and 12v dc output. You can charge it via ac or from solar. A little spendy at $1700 but it’s a small movable and portable unit.
I would be interested to hear your thoughts on the OPSEC implications of being the only powered home during a prolonged period of time without electrical infrastructure.
Depends on how ‘prolonged’ is. Five days isn’t as worrisome as five weeks or five months.
Add blackout curtains to your plans for OPSEC.
I had a similar bsystem to this when living in pa. I used a 24volt generic trickle charger that was originally on an industrial generator ( I still have this if your interested in a 2017 paratus gift). Then I had a 1000watt pure sign wave inverted connected to a couple breakers. I just switched the main power off and the inverted on and I could run a few priority items ( furnace, freezer, fridge). I’m offgrid now completely so the battery bank and inverters are allot bigger.
Careful- it seems proper preparedness promptly promotes pesky prolific problems. Yesterday I did maintenance on my $2 solar sidewalk lights… then the power went out three times over the next 12 hours. I finished brushing my teeth in the dark; at least I wasn’t on the can. The upside is I got to test my NVG without the usual light leaking into the house.
As for DC, good plan. You have good info on wire size vs. line loss, yes?
Im gathering more information as I go along. It’ll be an educational project.
A useful page:
http://www.calculator.net/voltage-drop-calculator.html?material=copper&wiresize=3.277&voltage=12&phase=dc&noofconductor=1&distance=100&distanceunit=feet&eres=1&x=79&y=6
Nice..I like that. Thx.
Definitely interested in how you do this. One of our long term goals is to put in a battery backup, charged by the solar panels, so as to reduce the need for a generator in the event of a power outage.
we have 4 deep cycle batts but we use solar panels to keep them topped off. we run an inverter and a 12v dc system. i hardwired led lights and a 12v plug in the basement, as thats where we normally stay when the power goes out. its a lot cooler down there so lack of ac isn’t such a big problem. we got hit with a derecho, a wall of wind several hundred miles across and doing 70 to 90 mph back in 2010. lost power for two weeks in 100 degree heat. the batts held their own for lights, battery charging, computer, a few hours of tv and running a fan to sleep by. back then we just had two sets of harbor freight panels, but have upgraded significantly since then. that was the longest two weeks ever, but we made it thru. we ran genny for the fridge until we figured out it needed pure sine wave and gave up on it. after abut ten days gas became available 50 miles or so away so i plugged a small window ac in to the genny and we could sleep upstairs again. i don’t know how we made it as kids w/out ac, lol.
Thinking about AC vs DC.
You’re still going to need an AC inverter to run the furnace, refrigerator and the power bricks for the IT gear. Why bother with a DC lighting system if you need to power larger inductive AC loads? Low voltage DC will require larger wire sizes for equivalent loads and that may account for some of the inverter loads you may deal with.
Wouldn’t it be more simple to isolate several receptacle sets around the house as a common emergency set and power those for emergency lighting and a few other critical AC loads?
Also, if you can swing a large APC type UPS or three, you could run some circuits through that via a set of twist lock cords that allow the inclusion of the UPS without hard wiring it.