Affordable 12v electric a/c compressor options?

Looks like most electric cars are running high-voltage a/c compressor pumps... Are there any reasonably priced 12v electric a/c compressors available? Is that even an option? Any oem options in the junkyards? Would simplify a mid-engined arrangement...
Thanks!
Dave
 

Joel K

Supporter
Dave,

A couple of the Ultima guys use this one, but is not inexpensive…

 

Neil

Supporter
Dave,

A couple of the Ultima guys use this one, but is not inexpensive…


Something isn't right. The 18cc version shows "1-3kW" but if one does the calculations: 12V x 30A = 360W and 12V x 55A = 660W ?????????
 
I was looking also this way out to cool down my (future) car, through electric compressor...... seems none of them actually working really on 12 volts, but the motor is or 110vac or 220/240vac.... and converted from12 volt battery... some times the converter is stand alone, or found a few with build in , on top of the compressor motor,..... and that's why you need at least 55 amps over 12 volts to feed the thing..., so big alternator & battery needed........
Paul
 

Howard Jones

Supporter
I had a partial plan in motion to use a separate belt system driven from an axle to drive an AC compressor. I was thinking I could take advantage of the motion of the car under braking as well as cruising speeds where the loss of a few hp to drive the alternator would not be noticed. Some consideration of pulley ratios would be in order but I think the compressor would begin working well enough at relatively low vehicle speeds. I was going to use a reverse switch to deactivate the clutch in reverse.

STOP and go traffic would be a problem but highway speeds or even low continuous speeds would still turn the compressor at an adequate rpm to function. Compressor speeds would need to be something like 1000-3000 RPMs I would think. A 27-inch tire turns about 350 RPMs @30 mph and a little over 1000 RPMs at 90 or so. This seems to indicate a pully drive ratio of about 3 to 1, again readily available pulley diameters around 2 1/2 to 7 inches would work.

I never followed through on this but all of the parts are readily available and this is completely doable.
 
STOP and go traffic would be a problem but highway speeds or even low continuous speeds would still turn the compressor at an adequate rpm to function. Compressor speeds would need to be something like 1000-3000 RPMs I would think. A 27-inch tire turns about 350 RPMs @30 mph and a little over 1000 RPMs at 90 or so. This seems to indicate a pully drive ratio of about 3 to 1, again readily available pulley diameters around 2 1/2 to 7 inches would work.

Stop-and-go traffic is probably when you'd need AC the most.
 

Howard Jones

Supporter
Stop-and-go traffic is no place for an SLC. A Prius is for commuting to work and back.

The thing that ended my plan above was rolling backward. I couldn't think of an easy way to address that one. I don't think an AC compressor would like to be turned backward.
 

Ian Anderson

Lifetime Supporter
Stop-and-go traffic is no place for an SLC. A Prius is for commuting to work and back.

The thing that ended my plan above was rolling backward. I couldn't think of an easy way to address that one. I don't think an AC compressor would like to be turned backward.
Chain drive with a bicycle ratchet pulley?

Ian
 
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