Auto voltage...24 , 32 , 48?

[Peter7307]

For a number of years now auto voltage has been based around a system running a nominal 12Volts.

And for about as many years prototype cars and concept vehicles have been paraded at auto shows touting the benefits of 24 , 32 and even 48 volt based systems.

So my question is are we any closer to having our vehicles based on higher voltages as many trucks and commercial vehicles already are or is 12 Volts going to be with us for some time to come?

Peter.

[busypaws]

The official safety standards are 42.4 VAC and 60 VDC. So exceeding those values you have to have extra safety provisions. "Orange" wires, cables with positive locking features, no exposed connnectors, water tight ...
So my vote (If that makes sense) is to have a 36Volt (minimum) battery and a 42 volt charging (alternator/voltage regulator). Thus when the alternator is running the vehicle is using 42 volts. When it is just the battery it is using something in the 36-39volt range.
Today 12 volt batteries are really closer to 12.8-13.2, and alternator output is 14.7volts. (It's late so don't quote me on the numbers)

Going to this size vehicle system I believe we could have belt driven starter/generators and engine off operation at stop lights. I also think 50-75 lbs of copper could be saved in every vehicle because the wire diameter could get smaller without insulation getting significantly bigger. (Copper weights more then plastic)

I saw lots of articles talking about 36/42 volt systems in the 99-01 time frame. I haven't seen much since.

It's the classic "chicken/egg problem"
Do battery manufactores and car manufactors drive a change to 36/42? How do you get all the guys building lights, wippers, windows, engine contorllers, radios ... change at the same time.

[Peter7307]

busypaws,
I also recall a burst of interest and coverage a few years ago and that is what prompted the question along with a growing recognition we are using non replaceable resources and reducing vehicle weight is one method to help extend fuel used in cars.

This is not my area of expertise so I posed the question here hoping someone more conversant with the subject would add what they know.
Thanks for the post.

Anyone else?

Peter.

[Piwoslaw]

Back in early to mid 1990's, I read about the automotive industry going to 36/42V systems. Then I stopped paying attention, because I knew that before they actually did, I'd already have hacked my car's electrical system and added a 24-36V starter/alternator...

[gone-ot]

...how long were they running on only 6VDC before 12VDC became universal?

...one fact: the higher the voltage, the lower the current has to be for the equivalent power!