Could an alternator be used to power a PC?

[3 Lions]

Just a question that popped into my head a few moments ago

[AshleyAshes]

So... You're asking if something that generates AC current can power something that runs on AC current? (Well, the PSU runs on AC).

 

Like, do you even know what an alternator is?  It produces alternating current, it's literally in it's name.  The current that runs through all our homes.

 

This question is about as sensible as asking 'Can you use water to quench thirst?' 

[3 Lions]

1 minute ago, AshleyAshes said:

Like, do you even know what an alternator is?

Yeah your speaking to a person that has got a level 1 vehicle maintenance qualification.  

[Beef Boss]

Just now, AshleyAshes said:

So... You're asking if something that generates AC current can power something that runs on AC current? (Well, the PSU runs on AC).

 

Like, do you even know what an alternator is?  It produces alternating current, it's literally in it's name.  The current that runs through all our homes.

 

This question is about as sensible as asking 'Can you use water to quench thirst?' 

More like salt water, BUT if you have a convertor @linustechtipsfanfromdarlo maybe. You know, like what a PSU does is change AC to DC

[AshleyAshes]

2 minutes ago, LinusTechTipsFanFromDarlo said:

Yeah your speaking to a person that has got a level 1 vehicle maintenance qualification.  

This isnt helping making you look less stupid in this thread..  

[Beef Boss]

2 minutes ago, AshleyAshes said:

This isnt helping making you look less stupid in this thread..  

Very rude. Trying to make an example by comparing water to thirst when salt water would be a better example. You need a filter or convertor to take out the salt or change it to DC. 

[3 Lions]

Just now, AshleyAshes said:

This isnt helping making you look less stupid in this thread..  

What ever you say...

[AshleyAshes]

6 minutes ago, BadluckBrian said:

Very rude. Trying to make an example by comparing water to thirst when salt water would be a better example. You need a filter or convertor to take out the salt or change it to DC. 

...that's what the power supply on the computer does already...

[Beef Boss]

3 minutes ago, AshleyAshes said:

...that's what the power supply on the computer does already...

And that's my point, thank you. 

[AshleyAshes]

2 minutes ago, BadluckBrian said:

And that's my point, thank you. 

Yes and those are already built into computers...

[Beef Boss]

10 minutes ago, AshleyAshes said:

Yes and those are already built into computers...

See how pointless it would be to use an alternator then? Haha, talk about high thermals 

[TetraSky]

If the computer has a Power Supply, it should be able to take the AC power that the Alternator generates, to power the PC, the same way it would if you'd plug it into a wall socket.

 

If the computer doesn't have a Power Supply, you're just gonna fry everything since a computer use DC and a PSU's role is to convert that AC to DC. Meaning you'd also require a converter.

 

This is what I got from reading the other comments, without the condescending opinions in them.

There's no such thing as a stupid question.

[Ithanul]

2 hours ago, TetraSky said:

If the computer has a Power Supply, it should be able to take the AC power that the Alternator generates, to power the PC, the same way it would if you'd plug it into a wall socket.

Though, I would think a PSU that is designed to hook into a wall socket is expecting a certain voltage and amps.  Then again, alternators do come with different ratings.  Most of the time I seen individuals do anything with alternators beside a vehicle is ones being driven by a belt hooked to bicycles, water mills, or wind mills then hooked to car batteries that are then wired to plugs to allow common electronics to run.  Or my favorite, re purposing one into a gas generator build.

[Drak3]

If it produces enough power for your vehicle and still supply the wattage to run your system and a transformer to output the right voltage.

[Unimportant]

Although a car-alternator will provide too low a voltage for a PC PSU. Full range PSU's are the most tolerant but still require a minimum voltage of 80-ish volts.

[iDeFecZx]

4 minutes ago, Unimportant said:

Although a car-alternator will provide too low a voltage for a PC PSU. Full range PSU's are the most tolerant but still require a minimum voltage of 80-ish volts.

How much voltage does a modern PC use? Alternators can output up to something like 22v these days

 

Ignore me, not reading things properly as per

[Unimportant]

Just now, iDeFecZx said:

How much voltage does a modern PC use? Alternators can output up to something like 22v these days

As said, full range PSU's start to go from somewhere around 80-ish volts.

 

Internally, A PC uses 12V, 5V and 3.3V DC - So it's possible to make a PSU that runs a PC off a 22V AC alternator, but your normal PSU won't do it.

[iDeFecZx]

1 minute ago, Unimportant said:

As said, full range PSU's start to go from somewhere around 80-ish volts.

 

Internally, A PC uses 12V, 5V and 3.3V DC - So it's possible to make a PSU that runs a PC off a 22V AC alternator, but your normal PSU won't do it.

I edited my initial post.

 

If you could make an alternator big enough and have something powerful enough to power it (one big fuck off diesel engine/generator) then in theory you could, but it wouldnt be worth the effort

[Beef Boss]

1 minute ago, iDeFecZx said:

I edited my initial post.

 

If you could make an alternator big enough and have something powerful enough to power it (one big fuck off diesel engine/generator) then in theory you could, but it wouldnt be worth the effort

Nuclear energy powered PC?

[iDeFecZx]

Just now, BadluckBrian said:

Nuclear energy powered PC?

sounds fruity

[Beef Boss]

Just now, iDeFecZx said:

sounds fruity

Added benefit; emits heat so you can cuddle with your nuclear canister. 

[tbake0155]

You can power a x86 motherboard from a car's battery/alternator.  Even though the motherboard needs 12V on the highest volt rail, and most car batteries are around 13 V when charged, the alternator will create spikes of over 100V (you can't see this on most voltmeter's because it happens too fast).  Those votlage spikes would kill a computer connected directly to the battery.  Of course, who would wire it that way.  I was only pointing that out because I think it's interesting.

 

There are power distribution boards made for exactly this.  You can hack a board like this out of some vehicles (since all modern cars have ECU's).

 

Here's an example of what I'm talking about: https://www.amazon.com/M4-ATX-HV-Intelligent-Power-Supply-6-34V/dp/B005TWE4YM

 

I've personally used that board with a 13 Volt power source and was able to run an underclocked i7 6700K (2.0 Ghz, approx. 30 Watts at full load) and a GTX 750 ti.  There's a lot of cool stuff you can imagine doing with a mobile computer like this. 

 

BTW, although a car will let you keep the computer on indefinitely as long as the car's motor is running, you can also build a mobile computer with a battery using a board like this... Endless possibilities!!

[vetali]

41 minutes ago, tbake0155 said:

the alternator will create spikes of over 100V

This is false. 

 

Most automotive alternators have 3 phases generating AC voltage rectified into DC voltage with diodes. This creates a kind of picket fence type waveform viewable on an oscilloscope. This would not work to power a computer because of the ripple assuming you had something to provide 3.3, 5, and 12 volt rails. 

[tbake0155]

12 hours ago, vetali said:

This is false. 

 

Most automotive alternators have 3 phases generating AC voltage rectified into DC voltage with diodes. This creates a kind of picket fence type waveform viewable on an oscilloscope. This would not work to power a computer because of the ripple assuming you had something to provide 3.3, 5, and 12 volt rails. 

I'm 99% sure that it's not false.  Unfortunately I can't seem to find a resource to describe this (searching google for car alternators is a huge hit).  The spikes will be fractions of a second and will not show up on a voltmeter, but they will destroy sensitive electronics.  If I had more time I'd search for it, but we can agree to disagree since it's not really a major issue. 

 

However, did you read the rest of my post?  There are power distribution boards available designed specifically to let a person power a motherboard from a car battery, although they can certainly be adapted for other purposes.

 

 

 

BTW, directly from the information listed with the power board I linked to in the previous post :

 

"M4-ATX-HV is a wide input (6 to 34V) vehicle / car / battery operated<br>ATX power supply capable of surviving tough car engine cranks (down to<br>6V) as well as transient over-voltage situations"

 

Regardless of the spikes, anyone can hook a motherboard up to a car's battery and create a mobile computer if that is what they intend to do.

[tbake0155]

Transient Over-voltage in a vehicle

http://m.littelfuse.com/~/media/electronics_technical/application_notes/varistors/littelfuse_suppression_of_transients_in_an_automotive_environment_application_note.pdf

 

 

Sorry for the double post, but searching for transient over-voltage pretty much clears this up.  If you still disagree, I consider you take your argument to an electrical engineer and not debate with me, since all I can do is regurgitate what I've seen on this topic.

 

Take care.