How Long Will a Car Battery (12v) Power a TV?

hey guys today we're gonna talk about how long this thing can power this thing let's get to it alright I promise we are going to get into it but before we do there's one thing I want to clear up it's a little bit of math so bear with me but it'll make it clear just how powerful a car battery is compared to a generator and it's not really that powerful so let's do a quick bit of math and this easily set up for you okay the math you're gonna hate me but it's easy its quick I just want to know what is the generator equivalent of our car battery I'm just gonna pick a generic deep-cycle battery just to show you and then you'll see what it is at the end if we have a 12-volt battery that is a hundred amp hours 12 volts times 100 amp hours gives us 1200 watt hours for that battery similarly if we take for instance my 1000 watt Sportsman inverter generator here that has 1000 max watts it has 800 running watts it advertises that it does half of the running watts so 400 watts for 6.3 hours on 0.55 gallons of fuel which is the size of that tank so 400 watts from here times 6.3 gives us two thousand five hundred twenty watt hours 1200 watt hours two thousand five hundred twenty watt hours if we divide the two so 1200 watt hours divided by 25 24 the battery to the generator there we are left with basically an efficiency factor for the battery of it is 0.47 six so 47.6% capacity basically that the generator has with these given parameters so that number here times the point five five gallons of gas gives us 0.25 to six times 128 ounces per gallon gives us thirty three point two eight ounces per or one core so a 100 amp hour battery is essentially the equivalent in an inverter generator of one quart of gas keep in mind that a car battery is about 50 amp hours on average maybe 60 some might get up into 70 so when you think about that put it in perspective you're dumping a jar of gasoline and an inverter generator and that's the max capacity you have in a battery from a hundred percent down to zero all right guys before we can do any of the math and calculations on determining how long this car battery can power this TV we need to know how many amp hours a car battery has typically if you know anything about batteries or 12-volt batteries you'll know that car batteries are starter batteries they're not rated in amp hours typically they won't have that on the sticker here they'll be rated in cold cranking amps or reserve capacity there's a problem because reserve capacity and cold cranking amps don't directly relate to amp hours so the best we can do and the best anyone can really do is just approximate and we're going to get to that next you can check out my link below and I will take you to a blog that I wrote where I extrapolated how a battery charging manufacturer company would rate certain cold cranking amps and reserve capacities as if they were AM hours so you can look at the sticker on your car battery see what the cold cranking amps or CCA is or the reserve capacity and find where you're at on the chart and that'll give you an approximation of where your amp hours are all right so just a little bit more math this is the chart right here that you'll find basically on my link below but it'll give you the different ranges of the cold cranking amps or the reserve capacity which is also on there and then what it would be equivalent what it would be for the amp hours so that is that there if you have a reserve capacity for instance my golf cart batteries for my battery bank my GC 2 s they have a 215 amp power rating at 20 hours or a reserve capacity of 395 minutes at 25 comparing these two doesn't really mesh it's like saying I have a four-minute mile er right here so he runs sixty seconds a lap he's labeled a four-minute mile er and this one's saying he runs 55 seconds per lap which is under 55 seconds for a half which is under 60 seconds so now he runs three quarters of a mile it's just a different way of looking at it how long can he run a mile versus he runs 55 seconds a lap what's the distance type thing so if you will have a reserve capacity of 395 at 25 amps and you were not given the amp hours you would do 395 times 25 amps which is what a reserve capacity is rated at at 25 amps unless stated otherwise divided by 60 minutes for the hour and it gives us a amp hour equivalency of a hundred and sixty four point five eight amp hours we already know that the actual amp hours are 215 at the 20 hour rate which is standard this one's telling us it'd be one sixty four point five eight because it's a higher draw the 25 amps is more than what the amperage would have been in this here here so 164 over 215 gives us about 76 or 75% if you go by the reserve capacity it's gonna be typically 75% of what the actual true amp hours are I calculated this across the board with several different batteries I was always very very ballpark it would I would be within about five or right on every single time by doing this equation so you take the reserve capacity 395 times 25 amps divided by 60 gives you that you take this number divide it by 0.75 and then you're gonna end up with pretty much what the actual amp hours are that's if you have reserve capacity if you have the cold cranking amps so for instance I took a look at my wife's vehicle she has 590 cold cranking amps and then based on this chart if I were to plug that in she'd be in this range here the 590 it probably be just over 58 so probably in 6065 range is what I would yes her actual amp-hours were actually stated on her battery 60 amp hours so it's definitely ballpark and let's move on now to powering this with this how to do it and how long you can get out of it alright guys I have a 32 inch vizio LED TV here that is rated at on the tag on the back at one point three amps so if you do 1.3 times 120 volts that's going to come up to 156 watts that's just not right upon my calculations so when I use a kilowatt which will measure the actual power going to a unit or an appliance I found that it actually draws maximum 40 watts instead of 156 and it usually settled between right around 30 plus or minus 5 at any given time that was despite me running a game console on it jacking up the volume and everything so I'm gonna go with a TV this size 32 inch LED uses about 30 watts so to hook up if you had to run your TV from your car battery you're gonna need an inverter unless your TV happens to have a direct current hookup a DC hookup like for a cigarette lighter but I doubt you have that if it's just your living room TV campers will have that or whatnot but we simply take the positive hook it on to the plus or the positive side of the battery and always wear safety glasses when dealing with batteries and then we will take the negative side and hook it up and I usually just twist them a little to make sure it has a good connection and then with this model which is a Duracell this one's discontinued but they do make a different 800 watt inverter just hold this in and that should power on tells us that we have 12 point 5 volts available this is a battery from 2016 so does not have the greatest strength in the world but it's still running in my car so why not I'll then plug in the TV to this and now this is a modified sine wave inverter so it will cause some distortion on the harmonics or whatever with the sound coming sound quality of the TV it's not terrible but it's definitely noticeable and the power hum oh right next to me there we go so I'm actually gonna unplug it again really quick put the kilowatt on here plug this in power this back on turn this to amps now this is telling me 1.3 I'm running 0.45 as its turning on and it'll fall down from there Oh point for the watts are at 31 30 32 30 so that's where it's basically hovering so now we want to know how long Kim the car battery power the TV that's what you all came for again a little bit of math we're gonna go with an average car battery smaller car having about 50 amp hours for this example but you can adjust the numbers for whatever your carburetor is when you consult that list on that link that I have below but 50 amp hours times 12 gives us 600 watt hours the LED 32-inch requires 30 watts actual we're gonna divide that by 0.85 to account for the 15 percent inverter and efficiency so for this inverter to convert direct current into alternating current for the TV you're gonna lose about 15 percent of your capacity so you divide that by 0.85 and you're gonna get approximately 35 watts total that are gonna be required by the TV to overcome the inefficiencies of the inverter from the batteries so 600 watt hours which we have here from the battery divided by 35 gives actually about 17 hours of straight use till you achieve 100% discharge of your battery or if you divide that in half if you want to have a chance at all to probably start your battery we go about eight and a half to start your car I mean we'd go about eight and a half hours for a 50% discharge now is it the smartest thing in the world to run a TV off of a car battery no a car battery has a different engineering inside of it how it was constructed it is a starter battery it is made to give a high amperage very quickly to start a car it is not intended as a deep cycle battery to rely on when the power goes out that would be what a marine battery or a golf cart battery a deep cycle battery at Rudy's deep cycle battery is used for they have thicker plates they don't give off as many cold cranking amps as high of an amperage at one time but they can go the long haul so this would be the Sprinter in the runners world and a deep cycle battery would be the marathoner and that's the one you want this one if you deep cycle it even below 30% you're doing damage to the battery below 50% you're really doing damage and if you deep cycle it all the way you're only gonna get away with that a handful of times maybe 10 12 times max you can do a deep cycle hundred percent discharge you your actual deep cycle batteries hundreds of times and get away with it though of course lose a little strength every time but they can keep up with it this will just give up the ghost after about a dozen or less times so you don't want to chance it with that okay so that's the basic number again you'd be able to get about eight and a half hours powering this off of your car battery it still have a possible chance of starting your car maybe you get away with a little more maybe a little less it all depends on a lot of things leading to my next point there are so many different variables and so many different limitations to these calculations because everybody's situation is different first of all everybody's TVs going to be different with your power requirements if you have an LED LCD plasma TV an old-school big box TV that all makes a difference so there's no one-size-fits-all you have to do the math your same thing goes with the battery the age of the battery how old is it is it brand new is it four years old like mine or it might just die at any time and maybe you're not going to get that full capacity out of it that you would get out of a brand new one what are the conditions of each of the cells in the batteries do you have there's six cells in here you have five that are in great condition and one that's bad so if you drain this down to 50% you know where you get the overall voltage of the battery if you were to test it with a voltmeter if you get it down to say eleven point five and all the cells are in good condition it might not start the battery but if you have five cells that are in great condition one cell that's bad and the overall state is eleven point five those five strong cells are making up the difference for the one it might still start your battery so there's way too many variables to go into making a definite determination on how long a car battery can run a TV safely and still be able to start your car if you need it to just don't be on that we have the amp hours there's no direct link between reserve capacity or cold cranking amps and amp hours so you can't tell one way or the other you can ballpark it and get close but again it's just another one of those limitations also this this is not taken to account for why you're doing it in the first place so if it's a power outage and you're looking to power your TV from your car battery you can't do much with just the TV so you're probably also going to be powering a DVD player a gaming console something like that to run an Xbox if I remember right I think it's 80 watts to run an Xbox to do this so that cuts your time down dramatically on how long you can power something with your car battery and of course just the overall damage that you're going to do to your battery is is it worth it with a battery being a hundred bucks you know especially if your batteries a year to old do you really want to start killing it prematurely when you might get another year or two out of it before I'm going to buy a new one that leads me to this why not just buy an easy fairly inexpensive inverter generator this thing weighs just over 20 pounds with the gasoline in it thousand watt peak 800 running Watts this thing is great I've had this for several years now there's really just not much to it just the choke lever here the whole cord fuel lever here you plug in what you need to and it's a this is an inverter generator so it's good for your electronics something like that might put you out 150 to 200 bucks consider a battery if you kill it as a hundred bucks anyways this thing is super quiet and it'll be great for your electronics so if you're look if you're in an apartment and you're able to sneak by with a generator like that it doesn't make a lot of noise if you're just a first-time homeowner or you don't know much about generators in general in Berger generators a great first generator buy for you it just kind of covers all of your bases for the smaller things so just the electronics you just wanna plug in your phone you just want to plug have some lights going you just want to have the TV you're not gonna be running your hair dryer off with it or your microwave or your well pump or anything like that just the basics to get through a short term maybe an eight-hour power outage and you want to have relative comfort infrared generate generator is the way to go it'll keep your TV running your cable box all of that stuff as long as you're still a cable or whatnot but yeah it'll still work for you let me just start this up really quick you can hear how quiet this is I'll keep talking at my normal level and we'll see where we go pointing at this outside you probably won't hear a bang [Music] alright guys sorry if this is a little long-winded hopefully that answered your question though I'm just how long a car battery can power a TV again my opinion is it's just not worth it the one caveat to that would be if your car is running while your battery is hooked up to the car and then you connect your inverter to the battery itself in which case your car then becomes a makeshift generator as well and they just got to run the cords from outside from your car inside just like you would if you had an inverter generator and then you're only limited basically by how much gasoline you have in your car last thing keep in mind that if you're going to start doing this as a thing you're gonna want want to probably invest in a pure sine wave inverter instead of a modified sine wave inverter these ones are cheaper however they run the risk of damaging certain electronics that have micro processors circuit boards things like that that need a very clean wavelength of alternating current like you would get from the wall these ones are more blocky of the current type so you might want to invest in that but if you just get an inverter generator like the one I have that I just showed you that is pure sine-wave so takes care of that for about 150 200 bucks you're good to go and the thing it's great yeah about 12 hours of use from my experience on one tank of gas with us very small load so anyways hopefully that answered your question helped you out if you liked it feel free to subscribe leave me a like or just like whatever you want to do doesn't matter leave a comment below if you have anything to add and have a great day thanks for watching

Channel: Home Battery Bank

Views: 217,882

Keywords: 12 volt battery, how long can a car battery power a tv, how long can a 12v, how long can a 12v battery run a tv

Id: U6-1IrGEgCI

Length: 19min 22sec (1162 seconds)

Published: Sat Apr 11 2020