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42-Volt Autos

michael posted more than 10 years ago | from the more-power dept.

Music 619

brianlmoon writes "Car Audio Electronics Magazine has a story about the auto industry switching to 36/42-Volt systems starting in 2004 and being completely switched by 2020. The demand for luxuries in cars has grown to where 12/14-Volts is just simply not enough. The automotive sound enthusiasts are going to benefit greatly as amplification will be much easier and cleaner with 3 times the voltage availble. Mobile computing will also benefit: "One of the real benefits of jumping to 42-volt systems, especially for hybrid vehicles, is the ability of the vehicle to offer regular 110-volt electrical outlets". It seems cars will have dual systems for a while for legacy equipment."

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w00t! (-1, Troll)

Anonymous Coward | more than 10 years ago | (#6205043)

...It's summer!

Oh great (2, Interesting)

ArchieBunker (132337) | more than 10 years ago | (#6205050)

Can't wait to see what these new batteries are going to cost...

Re:Oh great (-1, Troll)

Anonymous Coward | more than 10 years ago | (#6205060)


::mportant Stuff: Please try to keep posts on topic. Try to reply to other people's comments instead of starting new threads. Read other people's messages before posting your own to avoid simply duplicating what has already been said. Use a clear subject that describes what your message is about. Offtopic, Inflammatory, Inappropriate, Illegal, or Offensive comments might be moderated. (You can read everything, even moderated posts, by adjusting your threshold on the User Preferences Page) Problems regarding accounts or comment posting should be sent to CowboyNeal.

Bastards! (3, Funny)

Anonymous Coward | more than 10 years ago | (#6205059)

If they had chosen -56/48 VDC systems, cars would be compatible with Telco systems.

6 volts should be enough for anyone.. (4, Funny)

nurb432 (527695) | more than 10 years ago | (#6205062)

I remember hearing that from a commercial back in the early 50's...

Never create an artificial ceiling.. as it will be exceeded.. always.

Re:6 volts should be enough for anyone.. (5, Funny)

Anonymous Coward | more than 10 years ago | (#6205114)

Never create an artificial ceiling.. as it will be exceeded.. always.

299,792,458 meters per second should be enough for anyone.

Re:6 volts should be enough for anyone.. (3, Funny)

Mr Z (6791) | more than 10 years ago | (#6205162)

I think tachyons tend to disagree with you, but it's hard to tell since they seem like they're talking backwards.

bleh (2)

autopr0n (534291) | more than 10 years ago | (#6205142)

You can always convert one voltage to another though, it just entails a little bit of loss. Besides, you'd still have to take down the voltage for sensitive equipment anyway. You wouldn't want to run a modern CPU on 42 volts, that's for sure :P

It's only an optimization point. If you have a lot of low-voltage devices, you want a low voltage PS, and the same for high-voltage.

Re:bleh (1)

dsarrazin (304841) | more than 10 years ago | (#6205235)

What it allows for is lower current for the same amount of power. Lower current means thinner wires, which in turn lower the cost, and weight, of a car. Modern CPUS all run at 3.3V (or less) so the voltage has to be stepped-down anyways, the only change is the factor by which the voltage must be divided.

It should cost... (1)

ctrlfreak12 (670719) | more than 10 years ago | (#6205065)

It should cost 3 times as much, but with an extra cost for predicted inflation, the effects of actual inflation, the cost for the extra outlets, and some extra $$ just to confuse you, they will end up costing 9 times as much as a normal battery.

More accidents? (5, Insightful)

roryh (141204) | more than 10 years ago | (#6205069)

Most car drivers I see don't pay enough attention on the road as it is, and that's without the ability to plug in household applicances. Multi-car pileups because someone was checking their email or pr0n?

Re:More accidents? (4, Funny)

moofdaddy (570503) | more than 10 years ago | (#6205108)

The day I see someone making a smoothy as they drive down rt. 95 is the day I stop driving.

Re:More accidents? (1)

AceM2 (655504) | more than 10 years ago | (#6205258)

I've seen people shave, brush their teeth, put on makeup, talk on the phone, read maps, read BOOKS, watch their tv, and of course the worst is when they're trying to keep their kids in carseats.. I'm not sure a laptop in the car is going to be a big difference lol.. I remember driving an old 80s trans am once that had a small HUD on the windshield.. I think it's an option on newer corvettes too.. Now if they could display email, webpages, and (of course since everyone else brings it up..) porn on the windshield.. that would be very interesting.. State troopers should be happy cause they'll be able to give out more tickets and pretend that they're useful.

Powering a laptop (1)

BlueOtto (519047) | more than 10 years ago | (#6205070)

I already power my laptop in my car using a AC/DC power inverter. Works great!

AC/DC invertor? (0)

Anonymous Coward | more than 10 years ago | (#6205271)

That's kind of stupid. You're converting DC power from your car to AC for your laptop's AC adaptor that converts AC into DC for the laptop to use.

And I'm not even going to ask how much you're wasting doing that.

I may be incorrect, (1)

ehinojosa (220524) | more than 10 years ago | (#6205071)

but don't some BMW/Hummer/Lexus and some other luxury and european vehicles already use at least 24volt?

Re:I may be incorrect, (0)

Anonymous Coward | more than 10 years ago | (#6205109)

Almost all trucks(>4ton) uses 24 volt but some American trucks I worked on(Kenworth,Petersbuilt) used 12 volt. I am 99% sure that no modern car have used 24 volt.

hummers do (4, Informative)

Nf1nk (443791) | more than 10 years ago | (#6205135)

but only as legacy from being military vehicles, 24 volt systems ae needed to crank some of the old and new massive diesil engines in the transport trucks ect. the hummer has the 24 volt system so that it can jump start(or in military terms slave start)a tractor trailor.
since some military trucks spend a lot of time sitting and not driving this happens more than you might wish to think

For those unfortunate times... (5, Interesting)

reiggin (646111) | more than 10 years ago | (#6205073)

Does this mean if my new car has a 42v system and the car battery dies and leaves me stranded out in BFE, I have to wait for another 42v car to come by before I can get a jump? That would suck.

Re:For those unfortunate times... (5, Funny)

Drakin (415182) | more than 10 years ago | (#6205138)

Naw, just flag down 3 12 volt cars to give you a boost...

Re:For those unfortunate times... (0)

Anonymous Coward | more than 10 years ago | (#6205234)

Thanks, I needed that :))

Re:For those unfortunate times... (4, Funny)

Stigmata669 (517894) | more than 10 years ago | (#6205147)

No, you just need to jump start your car with 4 friends in parallel. I see a whole new brand of MONSTER(tm) jumper cables coming on.

Re:For those unfortunate times... (0)

Anonymous Coward | more than 10 years ago | (#6205172)

Im not sure but i think that a car with a 12 volt system will be able to give you a jumpstart. Relays works that way anyway. If you use a turnsignal-relay(24 volt) in a 12 volt car it will work but much slower. And if you use a 6 volt relay it will blink very fast. Not sure thou if it will be enough to start it.

Re:For those unfortunate times... (1)

s20451 (410424) | more than 10 years ago | (#6205201)

That would make sense if the timing was based on charging a capacitor.

Re:For those unfortunate times... (1)

jjeffries (17675) | more than 10 years ago | (#6205220)

No, you just need three and a half regular cars and some extra jumper cables.

Re:For those unfortunate times... (1)

me3head (621221) | more than 10 years ago | (#6205260)

You only need 3. Todays cars are considered 14 Volt systems and 3 x 14 = 42.

Re:For those unfortunate times... (4, Informative)

s20451 (410424) | more than 10 years ago | (#6205241)

Yes, you would be screwed if you had to charge a 42v battery from one 12v. Even four 12v in series might be a problem; the extra (48-42)=6v load would be dissipated in the battery, and shorting a few volts across a battery might not be good for it.

If the car companies had any brains, they would anticipate this problem. They could put some electronic thingy on the charging posts that automatically senses 12v and runs it through some power electronics to step it up to 42v. I don't know how efficient that would be.

Or, if the engine electrical system still runs on 12v (through a step-down), there could be a direct interface to the starter -- once the engine is started, the alternator takes over and charges the battery at 42v.

On the other hand, they could just go with the inelegant solution of designing an interface that makes it impossible to connect jumper cables. Then you would be in trouble.

Great, more cr*p in the atmosphere... (3, Interesting)

MosesJones (55544) | more than 10 years ago | (#6205077)

Sure it mentions Hybrids in there but we all know that it is the "luxury" cars driving these changes, larger power-supplies will require more power to charge, which in turn requires more fuel.

So excuse me if I don't "welcome" this so someone can have an even louder stereo while pumping even more chemicals into the atmosphere. So we can have 110v power supplies so... so what ? So a "busy exec" can have an even large mobile office ? So Ted and Rhona in the back can have a Playstation 2 each ?

I would say that goverments should be introducing regulations to reduce fuel emissions... but somehow in the country where this will be plonked into Canyenero style SUVs I doubt that the Oil President will concern himself with more fuel being used.

Re:Great, more cr*p in the atmosphere... (1)

Cloud 9 (42467) | more than 10 years ago | (#6205123)

And what do you drive?

A Train... (2, Funny)

MosesJones (55544) | more than 10 years ago | (#6205150)

Except I don't drive it, I have a chauffer who does it for me, there are also lots of other people who share the same chauffer :-)

Re:Great, more cr*p in the atmosphere... (2, Informative)

the_2nd_coming (444906) | more than 10 years ago | (#6205132)

don't worry....in a bout 10 years we should be recycling all our carbon so the crap we put in the air will eventualy get put back into the cars.


Re:Great, more cr*p in the atmosphere... (2, Informative)

wotevah (620758) | more than 10 years ago | (#6205206)

It depends on how many hungry things are hooked up, not how much voltage the battery has.

A higher voltage on the line is a good thing because it means less current through the wires, which in turn means less losses across them. Oh, and less current through the entire system means it is easier to keep a proper ground level across the entire chassis.

Re:Great, more cr*p in the atmosphere... (2, Informative)

pir8garth (674943) | more than 10 years ago | (#6205273)

It will actually make cars MORE fuel efficient by replacing bulky mechanical systems with electrical ones that would draw too much power on the current 12v systems. Not only will they be more efficient due to being electrical systems, but also weight will be improved for vehicles as well. The new standard was partly chosen to be 42v because the amperage levels would still be safe enough for people, but more than enough to compensate for the increase in vehicle electronics...

Also people's stereos won't necessarily be louder, but the equiptment will be smaller, more efficient and cheaper to manufacture, thus saving money.

In my eyes, this can only be a good thing, but it's too bad we'll all have to wait until 2020 for complete conversion...

Planned Obsolescence (1)

BierGuzzl (92635) | more than 10 years ago | (#6205080)

Why 42 volts? The first thing that comes up is how to convert it to 110V AC! Methinks the battery manufacturers are pushing for this mediocre solution in order to ensure that plenty of new batteries get on the market before replacing those yet again with a better standard. I tell ya, somewhere, there's warehouses full of soon to be obsolete batteries, and they're all going to waste.

Of course, in the unlikely event that exactly the opposite happens, and we experience a shortage of 12 V batteries, Just get in touch with me because I happen to have saved a few hundred of them from going to the junkyard and will be selling them at a modest profit.

What transparent commercialism you say... Indeed! Fight the establishment!

Why 42? (warning: douglas adams karma whoring) (4, Funny)

intermodal (534361) | more than 10 years ago | (#6205091)

of course, its because 42 is the answer to life, the universe, and everything!

Re:Why 42? (warning: douglas adams karma whoring) (0)

Anonymous Coward | more than 10 years ago | (#6205102)



Anonymous Coward | more than 10 years ago | (#6205133)

Anonymous Coward moderates YOU!

REDUNDANT AC declares post redundant.

news for nerds, stuff that matters.

Re:Planned Obsolescence (1)

the_2nd_coming (444906) | more than 10 years ago | (#6205152)


well we can always recycle them 100% and then turn the by products into new 42 volt batteries


Just my $.02: we are... (0)

Anonymous Coward | more than 10 years ago | (#6205083)

to power hungry these days.

btw. remember to switch of that 250watt monitor when you leave your desk for a coffee break (if you have a LCD, do the same).

Oh Great. (5, Funny)

robogun (466062) | more than 10 years ago | (#6205086)

My neighborhood already rocks with jackasses with 3,000 watt sound systems in their cars. Just what we need, 12,000 watt sound systems at 3 in the morning.

This is obvious (1)

Uart (29577) | more than 10 years ago | (#6205087)

Everybody knows that the answer is 42...


Re:This is obvious (2, Insightful)

throwaway18 (521472) | more than 10 years ago | (#6205253)

I remember an article in an IEE magazine about this a couple of years ago.

A nominal 12V car battery produces about 13.8V when fully charged. When it is being charged the voltage across the terminals can be as high as
15.5volts. The voltage also varies with temperature and load.

Electrical systems must meet more stringent safety requirements if they use 50V or more. 42V was chosen to keep within the 50V limit during charging.

Some people are confused about the reasons for a higer voltage. The amount of power used is volts*amps. With three times the voltage things like head lights that will be made to use the same power will require a third of the current so the wires can be thinner.

Simplifying somewhat, with a 12v supply and an 4ohm speaker a transformerless amplifier can supply about 24watts rms (0.707*v^2/R),
which is more than enough for everyone except boy racers.
Move to 42V and an amp can supply 72 watts per channel (marketing will call it 150Watts music power) without an expensive and bulky lump of iron and copper.

110 Volts? (1, Interesting)

Anonymous Coward | more than 10 years ago | (#6205089)

What's "regular" about 110 Volts?

If 36V is better than 12V, 230V surely must be better than 110.

Re:110 Volts? (0)

Anonymous Coward | more than 10 years ago | (#6205223)

It probably is, but at the same time shakes you twice as much.

Cool! (5, Funny)

Anonymous Coward | more than 10 years ago | (#6205093)

Now I can have 2 blue lights under my D-reg Ford Escort!

Re:Cool! (0)

Anonymous Coward | more than 10 years ago | (#6205119)

Is the bottom of your car fitted with glass and a hooker, or am I mixing up things.

dang, I need a jumpstart... (4, Interesting)

green pizza (159161) | more than 10 years ago | (#6205094)

This will be really nice when I find myself needing a jump... now I'll need three or four 12v batteries daisy chained to do a jumpstart.

Not to mention the other downsides (easier to get shocked from 36+ volts, easier for the electrical system to fry itself in a flood situation, etc).

Is it just me, or is the automotive industry quickly moving to purely disposable/recycleable cars? When I look at a 2003 model car, I have a hard time picturing it still running and still together in 15 years. Really makes me wonder what a 2010 model car will be like.

Re:dang, I need a jumpstart... (1)

the_2nd_coming (444906) | more than 10 years ago | (#6205179)

well, if you would stay away from chrysler cars and head down to ford or GM you have a good chance to get to 15 years...of cource if you went with a toyoda or honda car you are almost guranteed to get there...those suckers last for ever.

Re:dang, I need a jumpstart... (0)

Anonymous Coward | more than 10 years ago | (#6205272)

GM? You must be smoking crack... I'll be glad when my Pontiac hits 10 so I can trade it for a Honda.

Ummmm... (1, Interesting)

davidstrauss (544062) | more than 10 years ago | (#6205098)

I was always under the impression that clean amplification had to do with a clean, stable power source, not high voltage. Also, why does voltage matter for more power-hungry electronics? Amperage is the measure of load. Homes have exponentially increased power comsumption, yet the answer has been higer amperage wiring, not extensive high-voltage circuits. Finally, how does 42V DC convert much easier to 120V AC? Don't you still have to use an inverter?

Re:Ummmm... (1)

r_hutch (681483) | more than 10 years ago | (#6205130)

Well, the thing is that the car audio competitors can't make their wire any thicker and are running out of space... after all what comes after 0 gauge?

Re:Ummmm... (2, Insightful)

droleary (47999) | more than 10 years ago | (#6205196)

Finally, how does 42V DC convert much easier to 120V AC? Don't you still have to use an inverter?

Yeah, that's exactly what I was thinking. You can already get a pretty beefy inverter for under $100 to run equipment from your car. I think this is just another case of the big auto manufacturers tacking another $1000 on to the price of a car instead of giving us really innovative vehicles like this [acpropulsion.com] .

No more car tinkering... (1, Interesting)

zulux (112259) | more than 10 years ago | (#6205100)

On of the great things about 12V car systems - that (except for the coils and spark circut)is almost impossible to kill yourself electrically when you tinker with your car.

42 vols can kill you though - it can easily jump across wet skin.

Re:No more car tinkering... (4, Informative)

dougmc (70836) | more than 10 years ago | (#6205155)

42 vols can kill you though - it can easily jump across wet skin.
As can 12 volts. Or one volt.

It's just that more current will flow with 42 volts than 12 volts -- 3.5 times as much.

Also, to kill you, the current needs to flow through your heart (unless it's a LOT more voltage, pushing enough current to start cooking your flesh.) This means that you'd have to touch each terminal with a hand.

I remember the 68 volt batteries that they used for old flourescent lights. Even getting your fingers wet you could barely feel the voltage with them, and not at all having each hand touch a terminal. (Yes, I was a curious kid.)

In short, I don't see how 42 volts is going to kill you. Even 110 volts has a hard time doing it.

Re:No more car tinkering... (1)

Nf1nk (443791) | more than 10 years ago | (#6205158)

and car companies are all for the end of tinkering.
if you can't tinker for fear of death then you will aways take it to the dealership and pay $50 an hour to have minor work done n your car

Re:No more car tinkering... (0)

Anonymous Coward | more than 10 years ago | (#6205189)

I've touched something like 20,000,000 volts once and was fine. It's current that counts.

You could die touching 1V if the amps were high enough.

Re:No more car tinkering... (0)

Anonymous Coward | more than 10 years ago | (#6205250)

I've touched something like 20,000,000 volts once and was fine

Did you read /. before ?

Re:No more car tinkering... (0)

Anonymous Coward | more than 10 years ago | (#6205268)

it was a tesla coil, i had sex with it.

not true (0)

Anonymous Coward | more than 10 years ago | (#6205275)

That is false. 1V can't do anything to you unless somebody applies it directly to your neuron.

Touching any high-potential line will not do anything to you either unless the current has a path to ground through you. Even a small current (1uA) at 20MV will kill you instantly in that case because it will destroy your nervous system even without cooking anything else.

Re:No more car tinkering... (1)

Drakin (415182) | more than 10 years ago | (#6205246)

Yeah, but cars are getting less and less tinkerable all the time, between packing everything into a smaller space and the introduction of a lot more electronic controls, it's nothing like it once was...

good for the environment (4, Informative)

evenprime (324363) | more than 10 years ago | (#6205103)

Way cool. One of the arguments that the Big Three automakers have been offering for why they don't make ultra-efficient [technologyreview.com] ICE SUVs is that they require more expensive high voltage electrical systems. That's also one reason (albit a minor one) why gas-electric hybrids are so expensive.

Car manufacturers have said that it is more expensive for them if their product line has to have two different types of electrical systems. If high voltage electrical systems are going to be standard equipment, though, that argument will disappear.

Finally juice enough to do a real clean job (1)

plesseym (210173) | more than 10 years ago | (#6205104)

...vehicle to offer regular 110-volt electrical outlets...

I for one am waiting for the day I can run my "industrial sized" vacuum cleaner in my little Mitsubishi Lancer to get rid of those stubborn dust mites in the carpet.

2020! (1)

r_hutch (681483) | more than 10 years ago | (#6205105)

Wow, the car audio enthusiast will be basking in tons of kilowatts of power, but 2020 is a ways away... will they really need all those subwoofers and amplifiers once the rap trend fades out?

*THUMP* *THUMP* *THUMP* (4, Funny)

mizhi (186984) | more than 10 years ago | (#6205106)

Oh great, now instead of merely shaking the earth as they drive by, cars with souped up stereo systems will be able to actually crack the pavement and lift small dogs several inches off the ground.

More accessories... (4, Funny)

Visigothe (3176) | more than 10 years ago | (#6205115)

Why exactly is the ability to attach more electrical crap to my car a good thing?

Oh, I know... It's so I can check my email, sip my Vente Latte, talk on the phone, keep my McMuffin warm all while driving.

Woo Hoo! I am so glad I will be able to do that. I hate it when I get distracted by driving.

Re:More accessories... (1)

deadsaijinx* (637410) | more than 10 years ago | (#6205237)

Dear Visigothe,

It seems as though you have somehow missed basic geek brainwashing. Please report to the nearest re-education facility. You will soon see the light. More gadgets is good.

The Geek Enforcement

Saw this one coming when.. (4, Interesting)

The Optimizer (14168) | more than 10 years ago | (#6205118)

Saw this one coming when we bought a new car for my wife and it had a water cooled alternator!

Her car has more luxuries and gizmos than any of our previous cars: Navagation System, Universal Garage Door Opener, 11-speaker sound system w/ DSP, CD Changer, Rear hatch auto-closer (close hatch the last inch), 8 airbags, 16-way power seats, rear wiper arm, etc.. bla.. bla.. bla... and so on..

I talked to my mechanic about it and they already knew the 42-volt systems were coming. They said 42-volts was chosen to avoid amperages that would harm humans while providing enough capacity for all the stuff being piled onto the latest models.

It's a small miracle that the battery drain if the car isn't driven every day....

Re:Saw this one coming when.. (0)

Anonymous Coward | more than 10 years ago | (#6205204)

"chosen to avoid amperages that would harm humans"

Huh? I suggest a brief introductory course in the basics of electricity. Ohm's Law, specifically.

110VAC outlets available today (3, Informative)

autopr0n (534291) | more than 10 years ago | (#6205124)

Check it out. Just $20 or so [excess-solutions.com] . Radioshack sells an adaptor but it's $99. Fucking rip-off artists. There are a couple of cars out today that have 110VAC outlets already.

One of the main advantages of the 42 volt system is that you can have electronic, rather then hydrolic brakes.

Re:110VAC outlets available today (1)

virtual_mps (62997) | more than 10 years ago | (#6205208)

Yeah, you can convert 12VDC to 120VAC, but you need one heck of a lot of amps running through your car's electrical system in order to do it. Switching to 42VDC means you have less chance of melting the wires in your car.

Time for $5 gas^H^H^HPetrol (-1, Troll)

Anonymous Coward | more than 10 years ago | (#6205131)

Time for you to pay european prices you fat american slobs! Or do you wan't to "liberate" another country so you can afford to have a 10 litre engine in your new Ford XXXXLarge SUV so you can go though the drive thru in your local mcdonalds to by the new Xbox size fries to make your 70 inch wait grow even more!

Re:Time for $5 gas^H^H^HPetrol (-1, Offtopic)

Anonymous Coward | more than 10 years ago | (#6205176)


You can only think that way. Don't patronize there liberty.

Blasphemy.... (4, Funny)

di0s (582680) | more than 10 years ago | (#6205137)

It seems cars will have dual systems for a while for legacy equipment."
My late Ford Pinto isn't legacy equipment, you insensitive clod!

self sustaining arcs (2, Interesting)

Anonymous Coward | more than 10 years ago | (#6205146)

The only problem I see with this is that a 12V system cannot self sustain an arc while a 42V system easily can. If a 42V car gets in an accident, the higher voltage system may present a problem for emergency workers as they could receive a nasty electric shock while trying to open the car up to get the passengers out.

Headache (0, Redundant)

segfaultdot (462810) | more than 10 years ago | (#6205159)

The automotive sound enthusiasts are going to benefit greatly as amplification will be much easier and cleaner with 3 times the voltage availble.

Say goodbye to your peaceful, tranquil suburban paradise once the boomers get a hold of one of the supercharged amplifiers made possible by the increased voltage... sheesh, it's loud enough in my apartment complex already!

Some basic EE facts (4, Insightful)

Mononoke (88668) | more than 10 years ago | (#6205164)

Higher voltage system allows lighter gauge wire to carry the same amount of current (weight savings).

Higher voltage systems are less affected by corroded contacts and connections.

Higher voltage systems allow physically smaller fuses for the same power handling.

All of these allow cheaper cabling, connectors, fusing, etc.

Re:Some basic EE facts (3, Informative)

Mononoke (88668) | more than 10 years ago | (#6205186)

Higher voltage system allows lighter gauge wire to carry the same amount of current (weight savings).
Power, not current.

I'm a blockhead.

Re:Some basic EE facts (1)

Drakin (415182) | more than 10 years ago | (#6205192)

While it may be cheaper to use smaller gauge wire, it's also less durable. Saturn had a big problem with this with some of the earlier models at least.

Then again, the way the various companies seem to be going towards disposable cars (as noted by another poster) so I guess they don't really care.

That's bollocks (5, Informative)

Rosco P. Coltrane (209368) | more than 10 years ago | (#6205197)

A 42-volt system will slash weight

Where ? 12V lead/acid batteries have 6 elements, 42V batteries would have 21. That's 21 lead plates and associated acid cell. The only thing that would be lighter would wire harnesses, because the wires would be lower-gauge wiring since they wouldn't have to transport as much current. I can't see that being a real weight economy.

improve fuel economy

How ? do 42V alternators have a better efficiency than 12V ones ? And even if that was the case, wouldn't, say, driving the alternator with something else than a rubber belt improve efficiency much more dramatically ?

permit the replacement of many mechanical parts with electrical ones

How ? what are the mechanical parts that can't be replaced by 12V electrical equivalents that could be replaced by 42V ones ?

power all sorts of new gizmos like seat heaters, video, etc,

I can't wait to see cars with seat heaters or video units ...

and, of most concern to us, improve efficiency for all automotive electrical devices

I don't know about overall efficiency, but in all fairness, that's true : it's easier to step the voltage down than up. So yes, many devices would become lighter, cheaper and probably more efficient.

opening the door to higher audio amplifier power with far less complexity than the current crop of 12-volt, high-power amplifiers. Not only can will this translate to lower cost and more compact aftermarket power amps, even head units could cheaply integrate 100-plus RMS watts per channel power.

That's about the only application where I can see a 42V system be useful.

All I see in that "improvement" is trouble, exactly like when cars switched from 6V to 12V, and more money to aftermarket accessory makes. For many years, you'll have dual-voltage devices (complicated and defeating the purpose of having a higher voltage in the car) that will be more expensive and heavier, you'll have to buy another cell phone charger, power-supply, CB and whatnot, you'll have to use voltage converters, people without a clue will plug 12V devices in 42V cars, giving more money to garages, ... Okay, when the switch to 42V is made, then everything will supposedly be peachy. But that's not tomorrow : there are still cars around with 6V batteries, or negative hot, *today* while those standards are supposed to be long dead.

In short, a half-load of technical shit, trouble for everybody and a lot of money for the automotive industry ...

If people really cared... (0)

Anonymous Coward | more than 10 years ago | (#6205215)

They would focus on making safer cars first rather than any others. By safer I mean (a) cars that will not hurt other people on the road or damage other cars in a (any type of) collision and (b) cars that will not cause/contribute to pollution. But so long as greed and money rule the earth, people will continue to be stupid.

115 volt outlets are already in cars (1)

sahonen (680948) | more than 10 years ago | (#6205248)

I have a Pontiac Vibe, and it has a (non-grounded) 115 volt outlet in the dashboard. Just push a button to turn it on, plug in and voila. Now all I need is a GPS I can plug into my laptop and some map software.

Because we use more power. (1)

Openadvocate (573093) | more than 10 years ago | (#6205257)

It's because we use more power in the cars today. It's not just for lights and the engine anymore. Take a look at all the things that are put into cars today. 12v is a problem and you have to run thick cables to all these things. It is not very practical anymore. Fx some cars have eletric AC (for non-tropical locations).

42V is for steering, not audio (5, Informative)

Animats (122034) | more than 10 years ago | (#6205259)

This isn't about car audio; that's just where the poster found the story. This is about driving larger motors, like power steering. Power steering is about to go electric. The plants to build electric power steering units in volume have been under construction for months now. 12V power steering has been tried; it's on the Fiat Punto now. It doesn't work well, and scaling it up to larger vehicles hasn't been successful.

The 2004 Chevy Malibu will launch this fall with a 42V electrical system and Delphi E-Steer electrical power steering. It's not full steer-by-wire; there's still a mechanical linkage. But that's for backup, through a flexible coupling. The real steering is done with a sensor on the steering column, a motor in the steering box, and a computer watching speed, steering angle, skid information, and such.

This will make converting cars to computer control much easier.

This is a good thing. (4, Interesting)

dougmc (70836) | more than 10 years ago | (#6205261)

36 volts rather than 12 volts would mean that your wires could be 1/3rd the size and still transmit the same power. This is the real reason they're doing this.

The new batteries shouldn't cost 3x as much either. Yes, it will have 3x as many cells, but the cells could be 1/3rd the size, which could give the battery the same capacity as one of today. Of course, they do expect higher electricity demands in the future, so batteries will probably get larger (and would have to do so even if we stayed with 12v) so the size and price of batteries will probably increase somewhat.

As far as providing 110V AC circuits, they can do this pretty easily and cheaply now, if they wish. 36V systems won't make this that much easier. (It will make it easier to provide higher capacity 110v circuits, however. A hair dryer draws 1500 watts, which is 10 amps at 110 V or 125 amps at 12 volts. 10 amps is a lot, and 125 amps is massive. Assuming a 100% efficient inverter (which isn't possible), a 36v system could would only need 42 amps to power that hair dryer. Still a lot, but the wires needed to power the inverter would be a lot smaller.

(Of course, 42 amps is still a lot, and so it's unlikely that many cars will have an inverter capable of producing 1500 watts of power. But 500 seems likely.)

And no, I wouldn't expect this to affect the 1000+ watt stereos out there much. A 36v system would make wiring up one of these stereos simpler, because you could use smaller wires, but other than that it would be the same. The stereo could have some smaller wires internally as well, so in theory it might be a bit smaller and cheaper, but I'd expect that effect to be minimal.

Correct me (1)

SharpFang (651121) | more than 10 years ago | (#6205266)

if I'm wrong, but I heard 24V is the "lethal treshold" voltage, i.e. anything above it can kill, below - not (YMMV of course). So if your car breaks and you get your limb stuck with some powered element, with some bad luck you will fry to death, where 12V was safe, at worst giving you rather painful electric shock and some burns.
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