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12-volt battery to run my electric blanket?

36K views 29 replies 24 participants last post by  texican  
#1 ·
I've mentioned previously I live in an all-electric apt. bld.

We have no gas lines or other source of energy coming into the building and there is no back-up generator.

We are not permitted to have any kind of units that require canister or liquid propellants.

So, my question, if there were a power outage would a 12-volt battery work to run my electric blanket?

I know NOTHING about 12 volt batteries but I'm sure someone on here does.

thanks...stef
 
#5 ·
They actually DO make low voltage, DC electric blankets....with a 'wall wart' you plug into 120v AC and get 18-20v DC out on the blanket side.

From what I read, they use 80-100w for a twin to full size...twice that for a queen/king with 2 controls.

A 12v battery would actually work with this kind of blanket, of course, not for very long. Take a 100amp/hr battery, and assume the blanket is 18v/82watt...that's close to a 5amp draw. Assume you don't want to discharge the battery more than 50% ( or you will ruin it shortly ), you could run an 82w blanket about 10 hrs.

BUT you'd have to have some way to recharge the battery after one night.

AND you'd have to buy a low voltage blanket. Using a 120v would involve inverter, and more power loss...making it almost impractical.

I'd vote with Jim....spend the money on a couple of down comforters and not fool with batteries.
 
#7 ·
One other thing----some of these newer regular electric blankets will not run on a modified sine wave inverter. Never tried one on a true sine wave.

I just kept looking till I found some older, good shape electric blankets----They work good on Modified Sine!
 
#8 ·
Buy better blankets that don't require electricity.

Seriously. The money you put into getting your little electric blanket to work in a power outage would pay for about a half dozen really thick comforters which cannot fail, unlike an inverter, electric blanket, battery, etc.

If your body is generating heat (i.e., you're not dead) then if you have decent blankets, and enough of them, the heat will get trapped under there with you and keep you from freezing.

It gets down to sub-freezing in our cabin on some really cold winter nights and we don't freeze to death or even really feel cold so long as we're snug in our beds under the blankets.

Those are just the days we sit around and read our favorite books.
 
#9 ·
They ain't that cheap but check truck stops and online for a "bunk warmer". Its set up with a cigarette lighter plug and you can buy adapters with clamps to go on a battery and the other is a lighter receptacle.
 
#10 ·
They ain't that cheap but check truck stops and online for a "bunk warmer". Its set up with a cigarette lighter plug and you can buy adapters with clamps to go on a battery and the other is a lighter receptacle.
Like this?

http://electrowarmth.com/12-volt-bunk-warmers?url=12-volt-bunk-warmers

How would you use it indoors?
Assume I know nothing ( I don't), so you can't explain it too simply. :)

p.s. thanks for those suggesting down blankets or such, but I'm on blood thinner...it takes a while to get warm even w. an electric blanket...I need a "running start" so to speak that my own circulation doesn't provide.
 
#12 ·
Far far better than an electric blanket on top of you . .is a electric mattress pad....below you..
I use a mattress pad to warm up the bed before bed time . . .then I turn it off.

They are available in 12vdc or 110vac.

Yes the 12vdc mattress pads use a good 4 amps--when full on--less when the thermostat cycles . . . . .

Next morning how are you going to recharge that battery . . ??

Down comforters (the good ones) will last a very long time.........
 
#13 ·
They also make down sleeping bags that instead of being a bag have arms and legs. You can easily move around in them, one of my co-workers lived in one last winter when she had no heat! Would be a good back-up. Even if your blood is thinner you are still generating the same heat that can be captured to keep you warm.
 
#14 ·
The heck with conforming to them making rules of what you are allowed on hand for EMERGENCYS . Keep supplys on hand that you will need, and if it's a small propane heater for warmth/cooking then do what you have to do. Keep warm under blankets/coverlets. You could boil water make, oat meal, put hot cooked oatmeal in a zip lock bag and put it on you feet to keep get warm/keep warm in bed under the covers.
 
#16 ·
Like this?

http://electrowarmth.com/12-volt-bunk-warmers?url=12-volt-bunk-warmers

How would you use it indoors?
Assume I know nothing ( I don't), so you can't explain it too simply. :)

p.s. thanks for those suggesting down blankets or such, but I'm on blood thinner...it takes a while to get warm even w. an electric blanket...I need a "running start" so to speak that my own circulation doesn't provide.
Yes like that but you can find them cheaper but either way it isn't going to be a cheap fix.

There are a couple of ways to do it. From my quick research they draw about 4 amps which means for a 10 hour night they use 40 amp. If you are planning on using it a lot they way I'd suggest is getting a deep cell marine battery (made to be discharged and recharged),

a battery box to keep it in
Image


A 12 volt 6-12 amp battery charger
Image

and a pig tail adapter which lets you connect the warmer to the battery.
Image



You put the battery in the box, connect the charger and pigtail to it, and put the lid on. In the morning you plug the batter charger into the wall to recharge the battery. At night you unplug the charger from the wall and plug the warmer into the pigtail. In the morning unplug the warmer and plug in the charger. Repeat as necessary.


You MIGHT be able to buy a "jump box"
Image


It has everything already in one box (battery, charger and plug). The problems that pop into my mind are:

1) The battery maybe to small to power the warmer all night.

2) The charger might not be able to keep up with the draw in the long run. That is you take out 40 amps every night but the charger can only put in 30 amps back in during the day so after a couple of days the battery is dead.

3) They are not meant to be discharged and recharged over and over which might kill the battery in a hurry and they are not really made to have the quite expensive batteries replaced.
 
#17 ·
Yes like that but you can find them cheaper but either way it isn't going to be a cheap fix.

There are a couple of ways to do it. From my quick research they draw about 4 amps which means for a 10 hour night they use 40 amp. If you are planning on using it a lot they way I'd suggest is getting a deep cell marine battery (made to be discharged and recharged),

a battery box to keep it in
Image


A 12 volt 6-12 amp battery charger
Image

and a pig tail adapter which lets you connect the warmer to the battery.
Image



You put the battery in the box, connect the charger and pigtail to it, and put the lid on. In the morning you plug the batter charger into the wall to recharge the battery. At night you unplug the charger from the wall and plug the warmer into the pigtail. In the morning unplug the warmer and plug in the charger. Repeat as necessary.


You MIGHT be able to buy a "jump box"
Image


It has everything already in one box (battery, charger and plug). The problems that pop into my mind are:

1) The battery maybe to small to power the warmer all night.

2) The charger might not be able to keep up with the draw in the long run. That is you take out 40 amps every night but the charger can only put in 30 amps back in during the day so after a couple of days the battery is dead.

3) They are not meant to be discharged and recharged over and over which might kill the battery in a hurry and they are not really made to have the quite expensive batteries replaced.
Thanks for the excellent explanation and breakdown of details. I'm sure I'm not the only one who will benefit from this.

stef
 
#19 ·
Sears ( and probably others) have a unit with internal battery charger 12 V cig lighter connections and a light. It was designed for camping. The battery size is probably its shortcoming...but at keast everything else would be self contained.
 
#20 · (Edited)
Sure ... It would work .. get yourself one of the 12 volt to 110 converters. Plug your blankie in and try not to run it too high as that would use up the battery juice quicker. A deep cycle battery holds power longer than a car battery and would be better for a longer heating time. Charge the battery during the day, stay comfy at night !! It would be awesome if you could find a powerful solar charger for the battery ..... I've run alot of household stuff off 12 volt deep cycles during power outages.
Ohio Rusty ><>
 
#21 ·
Stef, if you're looking for heat during a power outage, don't wait for the blackout to try whatever you choose. Waking up shivering at 4am will be a lot more comfortable if you can just roll over & turn on the electric blanket because it was only a drill.

That said, here's a suggestion to go along with better blankets:
http://tipnut.com/make-your-own-microwave-heating-pad/

I went with one of DH's old tube socks. Added about 5 pounds of white rice & knotted the top. I nuke it in the microwave for 2 minutes, then another minute or two until it feels warm enough. Then tuck it under the bedclothes to warm where my feet will be. I put my feet against it to warm them & burrow icy toes into it. It still feels warm in the morning as long as it stays in the 'warm zone' under the covers. In fact just now the cat was snuggled up against the bump under the covers & that side felt warm when I pulled it out. So tonight I plan to put the bag under my sweater and carry it around for an hour before bedtime and see if that gets it warm enough to keep my toes happy. If not, there's always ($$) this off-grid microwave:
http://www.roadtrucker.com/12-volt-microwave-wavebox/12-volt-microwave.htm
 
#22 ·
southern people are so funny about cold

sleeping bags are the answer , they store well rolled up in the closet virtually forever

when you need them unzip get in zip up

my -40 degree bag as in rated for 40 degrees below zero will sweat you out on a 40 degree above zero night in a tent

you make the heat , you eat home made energy bars of oats , honey , nuts and fruit , that give you the energy to make the heat , you can eat anything you want but if your looking for maximum intake with minimal effort the home made power bars work well for winter camping .

if you need to make a bag that is say rated for +32 degrees these are cheap 25 dollars to get you another 5 degrees colder to say 27 degrees you make a simple fleece bag and put it inside the sleeping bag you get in the fleece then in the +32 degree bag


on a camping trip in say late august in northern Wisconsin it would not be uncommon to have 85 degrees during a day and a cold front move through and be 32 over night then back to 50 the next day , packing a fleece bag for the night that stays warm , a 40 degreee bag , and a flannel flat sheet with that combination you can fair a 32 degree night it won't generally freeze in the tent at 32 above you breathing keeps it a few degrees warmer and it is only 32 for a few hours on a typical late august cold night most of us use a 32 degree bag in September with a fleece bag it will get you to 27

you learn to get dressed fast and to keep you cloths in plastic bags so they stay dry from the dew

I know yall like to say it ain't the heat it's the humidity well it works the same way backwards
remember stay dry , cause it isn't the cold it's the damp , sweaty or wet that kills you

and if you get cold /wet like you went through the ice you get all the wet stuff off and dry as fast as you can then a warm person and the wet cold person get down to their undies and get in the bag together


I and many people store our spare sleeping bag in the car or truck all winter , I am a big guy I like my double sleeping bag and their is room for company if need be but with any extra bag if you have an oversized you roll over and tuck it under you , or you have that much more bag to heat up
 
#23 ·
Old fashioned hot water bottles would work if you have access to the hot water heater. You could drain the tank right into each bottle and they would help to keep you warm throughout the night. Of course this wouldn't work for a lengthy outage.

For a longer term outage, I would use a chafing dish and some tealight or votive candles to rig up a place to heat water and even food. The hot water could then be transferred into a hot water bottle.

These are the types of chafing dishes that I am referring to. Ignore the electric ones near the bottom of the page!

http://www1.macys.com/shop/search?keyword=chafing+dish
 
#24 ·
Two stay warmer ideas:
1) Sleep on top of a fleece blanket- no cold sheets ever!
2) My husband easily gets cold. We found that a 2 liter soda bottle filled with hot water from the tap **(NOT HEATED TO BOILING- NO!) with a tight cap, will stay warm for at least three hours under some blankets- next to your body. Feels so good when you get a bit hypothermic from working outside all day when it's cold... Use spouse, dogs, kids if the powers out...*(spouse probably will smell better).
 
#25 ·
A couple of hand warmers keep us warm when out camping in freezing weather. One by my feet and one up around the chest area. On clear days in the desert it will go from 70 to 30 when the sun goes down.