On the Gen III we just bought, it is completly beltless and the A/C is powered by the electric motor, I think... I think the Gen II does have a belt(s) that drives the AC compressor? If that is correct, how does the A/C run when the car is at a stop? I'm confused about this. Will someone please explain how the Gen II A/C works and how it is differant from the Gen III. I'm concidering trading in my Honda Fit on a '07 Prius, but here in Phoenix, will my city mileage tank with the A/C on 8 months out of the year? Thanks from the newbie.
Classic Prius (2001 - 2003 model years) has a belt-driven A/C compressor. 2G (2004 - 2009) has an electric compressor that receives power from the inverter, similar to 3G.
The Gen II still has engine belts, (not A/C) I know the water pump uses a belt as an example, but the Gen III is beltless. My fall milage is 5 MPG better than my summer MPG
Intresting, I figure I loose about 10% with the A/C in my Fit. I would have guessed less on the Prius, since recharging takes place anytime your coasting or braking.
I average about a 10% hit for AC use...perhaps a bit more in real hot temps. I suspect all autos with AC running take at least a similar penalty.
Recharging when you're coasting or braking is an important part of why the Prius gets good fuel efficiency, but that is irrelevent to the A/C. If you take energy to run the A/C then there is less for motive power, it's as simple as that.
I understand that. I just thought that there would be more energy for A/C because in my Fit, braking energy = waisted brake heat - while in the Prius, braking energy = charged battery = (some free)A/C. In other words instead of having free brake heat, having (through the recharged battery) free A/C. I'm easily confused.
Well sure it would work exactly like that if the regenerated energy were never used for any other purpose other than to run the A/C. What makes you think that the regenerated energy is not already used to provide motive power?
I'll take running the AC. Here where I live, one must use it or suffer. I noticed NO drop in MPG when using AC. I kept turning it off when I could, and there was no noticeable change in my MPG. Perhaps it is just my particular driving habits and commute. I'll say it again, people are just too anal about checking their MPG and comparing. If you want to lower you overall MPG, don't drive as much. I think having a Prius invites extra driving, as people think "why not, I get great mileage!" Stay home. Walk. Read. Talk to your children, instead of driving them to practice, the mall, the arcade, etc. My car sits several days a week. It gets GREAT MPG when it does... People think they are helping the environment by using a Prius, but you REALLY help it by NOT DRIVING as much as possible. THAT will (help) save the planet.
Same here in Northern KY. No noticeable drop when running the AC this summer. I usually just left the climate control in full "Auto" mode in the summer, with the cabin temp set to around 71 to 72 F. It did a good job of keeping the cabin cool. Of course, we did not have our usual hot summer this year. So it's probably not a fair comparison with the OP's Phoenix environs. I think that the AC would be more efficient in a G2 or G3 Prius in a climate like ours (around 90 F in a "normal" summer), than that found on cars with belt driven compressors. This is because with most cars, when the AC is on, it runs full bore. You make it "less cold" by mixing some warm air back in with the cold. But with the Prius' electric compressor, the compressor will run slower (using less energy) when it doesn't need to cool as much. An ingenious design.
Not belts. Belt. There is one small ribbed belt that runs the water pump for the engine. They eliminated that belt in the '10.
