question for a techie....

Battery.

snipped-for-privacy@TOGROUPmacconsult.com (Mike Rosenberg) wrote in news:1ij7jhx.o9gxde14y2ceiN% snipped-for-privacy@TOGROUPmacconsult.com:

hmmm....typing the word "battery" says little about the process of refrigeration..........thanks for the reply, i guess...........

tire.

The same system that your house uses.

Electricity.

The battery drives the AC system. If the battery gets low, the engine does whatever it needs to do at the time to charge the battery up so that it can continue to run the AC system.

Huh?

The refrigeration process is exactly the same--whether it's a Prius, a Buick, your home AC, or a refrigerator.

An electric motor turns the AC compressor. The battery runs the electric motor.

So, what system does the Prius use to run a compressor at all times? One word: battery.

Almost. That Buick (and all conventional cars) uses the engine - not an electric motor - to power the compressor.

The Prius compressor is motor-driven, but is that motor powered by 12V? Traction battery dc? Inverter output ac? Because it dissipates considerable power, it would be more efficient to run it from HIGH voltage, and probably ac after the inverter.

Ike

I just realized -- even a high efficiency compressor (vane, scroll) would require at least a 500W motor, so at 12V that would take more than 40 amps. It has to be high voltage.

This can be useful:

short answer: The Prius will cycle the AC compressor on and off as needed, keeping the fan on. The passenger requested temperature comes first. (Besides, the hybrid battery operates best at what humans consider "room temperature," so the cabin air is blown over the hybrid battery (which is located behind the passenger compartment).

On the NHW11 Prius (2001-2003 "Classic" sedan), like with most other cars the AC compressor is directly powered by a belt off of the gasoline engine. For the AC compressor to run, the gasoline engine will also run. (So, in the heat of summer, the engine may come on more often than otherwise just to power the AC compressor.) However, unless you have the front windshield defroster/defogger position selected or the MAX AC button pressed, the AC compressor does not run full-time/constantly (the ICE always on). (The front windshield defroster uses the AC compressor to dehumidify the air blown at the windshield, and that AC use gets its power from somewhere (and doesn't light the AC light to tell you the AC is being used)...) The AC compressor may be used if you have the AC button on, but not always. If at a stoplight, for example, and the cabin is already at/near the desired cool temperature, the ICE will still shut down, and the fans will continue to blow the remaining cold air into the cabin. When the air being blown into the cabin or the cabin itself gets too warm, the ICE may turn on (even while the car is stopped/idle) just to power the AC compressor. The AC compressor/ICE will cycle on/off as needed to maintain the coolness of the cabin.

On the NHW20 Prius (2004-current hatchback), the AC compressor is electrically driven by power from the hybrid traction battery. So, the gasoline engine is not required to power the AC compressor. However, should the charge of the hybrid traction battery become too low (say from a long time stopped while the AC is on), the gasoline engine will be restarted just to recharge the battery. But the ICE use is independent of the AC. See

An electric motor, drawing power from the traction battery. The 12V system is much too weak to power an A/C system for any length of time. If the A/C draws down the traction battery, eventually the engine will be started up to recharge the traction battery and provide power to the A/C motor.