John: no. I don't think I missed the point cause I read what you said well enough. I dunno too much, am not an engineer, so I make sure I listen to what others who know how to drive the hch2 say; and when I test the advice then I know why they get good mpgs and I can do the same on my own. (some of these other guys are engineers and thats good enough for me to)

The only way anyone can get good mpgs on the hch2 with the AC runnin is to keep the engine from driving the AC directly. no ifs and buts about it. But to do that you gotta set the temperature to a value that only lets the electric run. You are not going to get good mpg by telling hch2 owners to set the climate control to the lowest at any time unless youre going downhill with the ice off. I checked this and others who get 70 mpgs and more know it too.

ks

 

I somewhat agree, running the climate control with the A/C settings on LOW temperature and A/C forced on will more than likely force both the belt driven AND electric driven sides of the compressor to run for maximum cool down. That equals maximum load on the ice and maximum power draw from the battery pack. When the belt driven compressor is running on my car, i don't get a whole lot of regen either during cruising or braking since my foot is harder in it just to keep the car going from the addition load.

What I disagree on is that the belt driven compressor is going to gain you better MPGs then the electric compressor alone in low A/C load situations. The electric compressor is only 15 CCs vs 75 CCs for the belt driven compressor. If the demand is truely low on the A/C, that is, the car is cooled down and the system is only maintaining the temperature on a warm, but not extremely hot day, i say you'd get better MPGs with the AUTO climate control running the electric alone. The load on the ICE is noticeably less with one bar of regen keeping the electric going vs. then the significanlty larger belt driven compressor. Its the whole reason why whole house A/C systems that are multistage are more efficient then cycling a single, more power hungry compressor on and off.

When my battery was good, i could easily achieve 40+ with the A/C on and it running on the electric compressor alone, its great for high humidity but low temperature delta situations like rain...I thought the whole concept that we have a 3 stage compressor setup to vary the load vs. demand was pretty cool.