# Why don't cars have AC electrical plugs? **URL:** \ **Category:** Factual Questions\ **Created:** [August 5, 2007, 5:03pm UTC](https://boards.straightdope.com/t/why-dont-cars-have-ac-electrical-plugs/414518 "2007-08-05T17:03:18Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Cagey\_Drifter](https://avatars.discourse-cdn.com/v4/letter/c/b2d939/32.png) [@Cagey\_Drifter](https://boards.straightdope.com/u/Cagey_Drifter)\ **Post date:** [August 5, 2007, 5:03pm UTC](https://boards.straightdope.com/t/why-dont-cars-have-ac-electrical-plugs/414518/1 "2007-08-05T17:03:18Z")
Seriously, what’s with this cigarette lighter BS where you have to get special cables and adapters? Shouldn’t newer models have this for the ‘laptop’ and ‘ipod’ crowds? ---
**Author:** ![Crafter\_Man](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crafter_man/32/458_2.png) [@Crafter\_Man](https://boards.straightdope.com/u/Crafter_Man)\ **Post date:** [August 5, 2007, 5:18pm UTC](https://boards.straightdope.com/t/why-dont-cars-have-ac-electrical-plugs/414518/2 "2007-08-05T17:18:45Z")
Personally, I can’t stand the “cigarette lighter plug” format. Very outdated. Of course, for AC the vehicle would need a built-in inverter. This adds cost. ---
**Author:** ![ChrisBooth12](https://avatars.discourse-cdn.com/v4/letter/c/e95f7d/32.png) [@ChrisBooth12](https://boards.straightdope.com/u/ChrisBooth12)\ **Post date:** [August 5, 2007, 5:20pm UTC](https://boards.straightdope.com/t/why-dont-cars-have-ac-electrical-plugs/414518/3 "2007-08-05T17:20:05Z")
Probably because they didnt want people to attach TVs and Microwaves. ---
**Author:** ![IAmNotSpartacus](https://avatars.discourse-cdn.com/v4/letter/i/cc9497/32.png) [@IAmNotSpartacus](https://boards.straightdope.com/u/IAmNotSpartacus)\ **Post date:** [August 5, 2007, 5:26pm UTC](https://boards.straightdope.com/t/why-dont-cars-have-ac-electrical-plugs/414518/4 "2007-08-05T17:26:00Z")
[QUOTE=Cagey Drifter] Seriously, what’s with this cigarette lighter BS where you have to get special cables and adapters? Shouldn’t newer models have this for the ‘laptop’ and ‘ipod’ crowds? [/QUOTE] Most of these items run off DC anyway. The stock transformer simply converts the AC to DC. So you’re converting DC to AC and then back to DC. That doesn’t make much sense now does it? ---
**Author:** ![habs](https://avatars.discourse-cdn.com/v4/letter/h/ecae2f/32.png) [@habs](https://boards.straightdope.com/u/habs)\ **Post date:** [August 5, 2007, 5:35pm UTC](https://boards.straightdope.com/t/why-dont-cars-have-ac-electrical-plugs/414518/5 "2007-08-05T17:35:03Z")
Some cars, such as the [Pontiac Vibe](http://townhall-talk.edmunds.com/WebX?14@@.eea1341/2598), have 12v electrical plugs… ---
**Author:** ![Crafter\_Man](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crafter_man/32/458_2.png) [@Crafter\_Man](https://boards.straightdope.com/u/Crafter_Man)\ **Post date:** [August 5, 2007, 5:55pm UTC](https://boards.straightdope.com/t/why-dont-cars-have-ac-electrical-plugs/414518/6 "2007-08-05T17:55:41Z")
[QUOTE=IAmNotSpartacus] Most of these items run off DC anyway. The stock transformer simply converts the AC to DC. So you’re converting DC to AC and then back to DC. That doesn’t make much sense now does it? [/QUOTE] Correct me if I’m wrong, but a lot of things are designed to be powered off a DC voltage \*other \* than 12 VDC. In which case a DC-to-DC converter is still required. (Unless the appliance is redesigned to be powered from 12 VDC.) And what about things w/ motors? AC motors are more efficient than DC motors. There’s no clean solution. Finally, let’s not forget the fact newer cars will have a higher voltage battery. (48 V?) ---
**Author:** ![I\_m\_Ron\_Burgundy](https://avatars.discourse-cdn.com/v4/letter/i/9fc29f/32.png) [@I\_m\_Ron\_Burgundy](https://boards.straightdope.com/u/I_m_Ron_Burgundy)\ **Post date:** [August 5, 2007, 6:03pm UTC](https://boards.straightdope.com/t/why-dont-cars-have-ac-electrical-plugs/414518/7 "2007-08-05T18:03:19Z")
[QUOTE=Cagey Drifter] Seriously, what’s with this cigarette lighter BS where you have to get special cables and adapters? Shouldn’t newer models have this for the ‘laptop’ and ‘ipod’ crowds? [/QUOTE] They’re not meant to be mobile homes, they’re cars, vehicles intended for transport. I’m sure Apple and Griffin make billions off the ipod car chargers. Besides, what are you doing that you need a laptop in the car? Shouldn’t you be driving? ---
**Author:** ![Tamex](https://avatars.discourse-cdn.com/v4/letter/t/ccd318/32.png) [@Tamex](https://boards.straightdope.com/u/Tamex)\ **Post date:** [August 5, 2007, 6:08pm UTC](https://boards.straightdope.com/t/why-dont-cars-have-ac-electrical-plugs/414518/8 "2007-08-05T18:08:29Z")
They used to. When I was growing up, my parents had a 1973 GMC Jimmy SUV (well, that’s what you’d call it today, anyway) that had an electrical plug in the dash. I do not recall ever seeing it used. It was truly a feature ahead of its time. What would you have used it for back then? I hadn’t thought about that for years until I needed to get a converter so that I could charge my Macbook Pro in the car. Now you have so many things that get recharged, like cell phones, laptops, iPods, digital camera batteries, etc. that it would be an invaluable feature. I’m sure it will be coming back. ---
**Author:** ![Myglaren](https://avatars.discourse-cdn.com/v4/letter/m/f1d935/32.png) [@Myglaren](https://boards.straightdope.com/u/Myglaren)\ **Post date:** [August 5, 2007, 6:50pm UTC](https://boards.straightdope.com/t/why-dont-cars-have-ac-electrical-plugs/414518/9 "2007-08-05T18:50:21Z")
You only need a regulator to drop the voltage from 12v DC to whatever is required - I have a couple of in-car chargers for my camera’s batteries that do just that. The car I have now also has power outlets between the front seats and in the rear loadspace. Not sure how these would work for a longer period as the car shuts down all electrical activity other than locks after 45~60 mins. if there is a current drain. (not when the engine is running of course) An AC generator in the car would add significantly to the cost for something that most people would hardly ever use, if at all. ---
**Author:** ![garygnu](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/garygnu/32/2924_2.png) [@garygnu](https://boards.straightdope.com/u/garygnu)\ **Post date:** [August 5, 2007, 6:58pm UTC](https://boards.straightdope.com/t/why-dont-cars-have-ac-electrical-plugs/414518/10 "2007-08-05T18:58:07Z")
How long would a car battery power, say, a Oster blender making margaritas on a “camping” trip? ---
**Author:** ![doreen](https://avatars.discourse-cdn.com/v4/letter/d/858c86/32.png) [@doreen](https://boards.straightdope.com/u/doreen)\ **Post date:** [August 5, 2007, 7:19pm UTC](https://boards.straightdope.com/t/why-dont-cars-have-ac-electrical-plugs/414518/11 "2007-08-05T19:19:22Z")
[QUOTE=Crafter\_Man] Personally, I can’t stand the “cigarette lighter plug” format. Very outdated. Of course, for AC the vehicle would need a built-in inverter. This adds cost. [/QUOTE] The inverter doesn’t have to be built in . Cost me about $20 to buy an inverter that plugs into the lighter outlet. I don’t have to buy special chargers and adapters for different devices. ---
**Author:** ![IAmNotSpartacus](https://avatars.discourse-cdn.com/v4/letter/i/cc9497/32.png) [@IAmNotSpartacus](https://boards.straightdope.com/u/IAmNotSpartacus)\ **Post date:** [August 5, 2007, 7:21pm UTC](https://boards.straightdope.com/t/why-dont-cars-have-ac-electrical-plugs/414518/12 "2007-08-05T19:21:30Z")
[QUOTE=garygnu] How long would a car battery power, say, a Oster blender making margaritas on a “camping” trip? [/QUOTE] That will be a function of how much current the device pulls and the capacity of your car battery. I know that for my RC batteries that are about 800mAh capacity, I am told I can get 5 charges off my car battery before I need to turn it over and let the alternator charge it back up. So that tells me my battery has a capacity greater than 4Ah. ---
**Author:** ![Tuckerfan](https://avatars.discourse-cdn.com/v4/letter/t/eada6e/32.png) [@Tuckerfan](https://boards.straightdope.com/u/Tuckerfan)\ **Post date:** [August 5, 2007, 7:26pm UTC](https://boards.straightdope.com/t/why-dont-cars-have-ac-electrical-plugs/414518/13 "2007-08-05T19:26:42Z")
[QUOTE=Crafter\_Man] Finally, let’s not forget the fact newer cars will have a higher voltage battery. (48 V?) [/QUOTE] They keep saying that’s coming, but it never seems to show up. There are/were models of GM pickups that had a generator built in to the transmission’s flywheel, with electrical outlets in the bed or fenders (I forget which). ---
**Author:** ![Myglaren](https://avatars.discourse-cdn.com/v4/letter/m/f1d935/32.png) [@Myglaren](https://boards.straightdope.com/u/Myglaren)\ **Post date:** [August 5, 2007, 7:26pm UTC](https://boards.straightdope.com/t/why-dont-cars-have-ac-electrical-plugs/414518/14 "2007-08-05T19:26:52Z")
[QUOTE=doreen] The inverter doesn’t have to be built in . Cost me about $20 to buy an inverter that plugs into the lighter outlet. I don’t have to buy special chargers and adapters for different devices. [/QUOTE] Just anecdotal but a friend of a friend is supposed to have bought a cheap inverter that destroyed his laptop battery. Unless the voltage is being stepped up I can’t see the need for one. What’s the output voltage? ---
**Author:** ![Bryan\_Ekers](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bryan_ekers/32/183_2.png) [@Bryan\_Ekers](https://boards.straightdope.com/u/Bryan_Ekers)\ **Post date:** [August 5, 2007, 7:29pm UTC](https://boards.straightdope.com/t/why-dont-cars-have-ac-electrical-plugs/414518/15 "2007-08-05T19:29:06Z")
[QUOTE=garygnu] How long would a car battery power, say, a Oster blender making margaritas on a “camping” trip? [/QUOTE] Better make sure your Septuple-A membership is paid up. ---
**Author:** ![groman](https://avatars.discourse-cdn.com/v4/letter/g/73ab20/32.png) [@groman](https://boards.straightdope.com/u/groman)\ **Post date:** [August 5, 2007, 7:33pm UTC](https://boards.straightdope.com/t/why-dont-cars-have-ac-electrical-plugs/414518/16 "2007-08-05T19:33:59Z")
[QUOTE=IAmNotSpartacus] That will be a function of how much current the device pulls and the capacity of your car battery. I know that for my RC batteries that are about 800mAh capacity, I am told I can get 5 charges off my car battery before I need to turn it over and let the alternator charge it back up. So that tells me my battery has a capacity greater than 4Ah. [/QUOTE] According to [Wikipedia](http://en.wikipedia.org/wiki/Car_battery) > [@](#): > > Reserve capacity minutes (RCM), also referred to as reserve capacity (RC), is a battery’s ability to sustain a minimum stated electrical load; it is defined as the time (in minutes) that a lead-acid battery at 80 °F (27 °C) will continuously deliver 25 amperes before its voltage drops below 10.5 volts. and my car battery is rated at 100 minute RCM, which I would say is about 40 Ah. Although car batteries aren’t designed for that kind of abuse and that would be the reason you’re advised against charging your RC batteries off your car battery more than 5 times without recharging the latter. ---
**Author:** ![groman](https://avatars.discourse-cdn.com/v4/letter/g/73ab20/32.png) [@groman](https://boards.straightdope.com/u/groman)\ **Post date:** [August 5, 2007, 7:41pm UTC](https://boards.straightdope.com/t/why-dont-cars-have-ac-electrical-plugs/414518/17 "2007-08-05T19:41:55Z")
[QUOTE=Myglaren] Just anecdotal but a friend of a friend is supposed to have bought a cheap inverter that destroyed his laptop battery. Unless the voltage is being stepped up I can’t see the need for one. What’s the output voltage? [/QUOTE] The output voltage of an inverter is typically 100 - 120V 60Hz AC, hence the need for an inverter rather than a DC-to-DC vreg. [QUOTE=garygnu] How long would a car battery power, say, a Oster blender making margaritas on a “camping” trip? [/QUOTE] I don’t know the power rating of your Oster blender, but if I use my 400W Hamilton Beach as a reference then the draw is going to be about a 33A if I’d use an ideal inverter. Seeing as how there’s no such thing, let’s say 35A (seeing as how the blender is rated 400W MAX, it won’t be drawing 400W all the time either). Using my 100 minute battery mentioned above as a reference, you’ll get (accounting for the voltage drop) a little less than an hour. Of course your car won’t start after this, but you shouldn’t be in any condition to drive anyway 😉 If you’re really hardcore you can throw in one of [these babies](http://www.odysseybatteries.com/battery/pc2150.htm) in your trunk as a dedicated blending battery and this would give you 2 hours of margarita blending time without putting your ability to drive drunk in jeopardy by draining your main battery. ---
**Author:** ![Joey\_P](https://avatars.discourse-cdn.com/v4/letter/j/919ad9/32.png) [@Joey\_P](https://boards.straightdope.com/u/Joey_P)\ **Post date:** [August 5, 2007, 8:01pm UTC](https://boards.straightdope.com/t/why-dont-cars-have-ac-electrical-plugs/414518/18 "2007-08-05T20:01:41Z")
When my wife had a Toyota Matrix (not sure what year 04 or 05 I think) it had a 100w 120v AC outlet built right into the dash. ---
**Author:** ![Tamex](https://avatars.discourse-cdn.com/v4/letter/t/ccd318/32.png) [@Tamex](https://boards.straightdope.com/u/Tamex)\ **Post date:** [August 5, 2007, 8:13pm UTC](https://boards.straightdope.com/t/why-dont-cars-have-ac-electrical-plugs/414518/19 "2007-08-05T20:13:13Z")
[QUOTE=Bryan Ekers] Better make sure your Septuple-A membership is paid up. [/QUOTE] AA and AAA…where do the other two A’s come in? ---
**Author:** ![Do\_Not\_Taunt](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/do_not_taunt/32/2968_2.png) [@Do\_Not\_Taunt](https://boards.straightdope.com/u/Do_Not_Taunt)\ **Post date:** [August 5, 2007, 8:44pm UTC](https://boards.straightdope.com/t/why-dont-cars-have-ac-electrical-plugs/414518/20 "2007-08-05T20:44:05Z")
[QUOTE=I’m Ron Burgundy?] Besides, what are you doing that you need a laptop in the car? Shouldn’t you be driving? [/QUOTE] You know, sometimes there are _non-drivers_ in the car, too. [Next page](https://boards.straightdope.com/t/why-dont-cars-have-ac-electrical-plugs/414518.md?page=2)