High Ambient Temperature causing 400-450 Wh/mile usage?

[joebob73]

With the summer months arriving, my car is showing a much higher average Wh/m (somewhere around the 400-450 range). I do mostly local driving with a lot of short 10-15 mile trips and some of them average up to 500 Wh/mile. I can hear the external fan running very loudly when my A/C is on but the cabin temperature is well managed (I keep it at 69 degrees). Obviously this high power drainage is having a drastic effect on my range. Is anyone else having this issue?

I have a service appointment in two weeks and will have them take a look at it. I wonder if I have one of those cars with the crossed refrigerant/condenser lines.

 

[Electric700]

Up to 500 Wh/mile seems high, so as you indicated there may be something wrong that is causing your AC to work very hard. Until they take a look, try cooling off your vehicle with the app about 10 minutes before you need to use the car.

Also when the external fan is very loud, I am able to get mine to quiet down by lowering the fan speed manually. The exception is when I have the car charging at a Supercharger, since the AC works harder to cool the battery then.

 

[CHG-ON]

My guess would be that if you are only driving around town at low speeds and it is in the, say, 90's and the car has been heat soaked by sitting outside, I can easily see that kind of usage. If you were on the freeway, I bet it would come down because the car would benefit more by passive cooling. I do see rates that high for the first few miles when the car is heat soaked. But I am rarely in slow traffic, so she cools down after a few miles.

 

[David99]

With the summer months arriving, my car is showing a much higher average Wh/m (somewhere around the 400-450 range). I do mostly local driving with a lot of short 10-15 mile trips and some of them average up to 500 Wh/mile. I can hear the external fan running very loudly when my A/C is on but the cabin temperature is well managed (I keep it at 69 degrees). Obviously this high power drainage is having a drastic effect on my range. Is anyone else having this issue?

I have a service appointment in two weeks and will have them take a look at it. I wonder if I have one of those cars with the crossed refrigerant/condenser lines.

It always takes a lot of extra energy to cool down or heat up a car initially. So it does make sense to see much higher energy usage on shorter trips. AC usage also becomes proportionally higher when driving a low average speed. Say you are driving 30 mph it takes twice the time to drive the same distance than driving at 60 mph. That means the AC uses twice as much energy over the same amount of miles.

 

[joebob73]

Thanks for the response guys. The comments make sense, but I also hope to see if there is something that can be improved during the service visit. Will update the thread after the visit.

 

[ptsagcy]

If you don't have passengers in the 3rd row, turning off the rear a/c makes a big difference. I've seen initial numbers, in a heat soaked car, over 1,000 wh/mi but it comes down quickly as you drive. Pre-cooling while it's still plugged in obviously is a great help.

 

[Muzzman1]

@joebob73
We are experiencing the exact same #'s in the 90X with the same driving style. My wife drives her X and in 5k miles her average is 470wh/mi. Even on a 150mi round trip with me driving I could only get 351wh/mi. We always have the rear HVAC on because we have 2 kids under 3.
It has be a bit worried when we start doing long road trips, as I suspect we will get about 225miles from 0-100 SOC. (79kw/.351) I would hate to have to charge to 100% at many SC's to make it to the next!

 

[FroglegsX2015]

Around town on hot days, 450Wh/mile easily with AC at low 60's and fan 6-8. Short trips, parking in shade, running AC while out of car 5-10 min. Thought it was normal, but AC died today. Not sure. I couldn't find any other reports in search about air conditioner dying. I'll find out next week.

 

[shokunin]

Froglegs, there have been several reports of X's air conditioning just quitting and dying. I don't think you're alone on this issue.

 

[joebob73]

Got my car back and techs did not find any issues or crossed condenser lines with the AC system. I guess it is normal to have these high energy usage on short trips. When I had my loaner Model S, I also noticed usage in the 380Wh/mile range on my short trips. With the X being a bigger car to cool, I guess that makes sense.