EV range increasing winter - summer

Your Eco Diary looks much like mine, although mine is bit more extreme! EV range in the 0's in the winter, 20's in the spring, and 30's in the summer. Now the temp is in 50s, I am getting much better EV range than Feb when the temp was single digit to sub-zero.

 

That’s a good illustration!

Here in Austin TX, the difference is not quite so extreme, thankfully, and if anything, it goes the other direction due to air-conditioner use.

 

Mine is the opposite. It was WAY better back in March. No A/C needed. Now it's running full blast.

 

That is consistent with electric heater using more energy than air conditioning uses

 

I noticed yesterday that with the system in Eco and a set point of 78F, my A/C load percentage was 25%. That was on 35 mph streets, but ... Sheesh!!!!

 

I do that. But, at least for A/C, there is a corelation. But it involves how much the motor is using vs the A/C so it's complex.

 

i'm up to 14 miles

 

Hey when I was more fit I could walk that distance in a day

Now I sit in front of a computer and drink coffee

 

Over the weekend when I was down south, I used A/C for cooling for the first time this season. The out side temperature reached 87F.

I had my AC set at 74 AUTO to prevent too much AC running. I usually keeps my AUTO setting at 70F at home. The A/C load for the day went up to 27%. This with ambient temp only at low to mid 80s. The problem, when I returned home yesterday. I could feel warm air coming out of the vent. The HEAT was on! I had the AUTO setting at 74F, and ambient temp at home was 64F. If I set my AC to 78F like you do, I will have HEAT ON most of summer.

Since, I have far more days of colder temp when heat is needed than days when I have to use AC to cool the cabin, I think you are correct that heater use more energy than air conditioning overall at my location. However, is that also true if the temp difference is exactly the same? Say, if the ambient temp is 100F and inside cabin temp is also 100F, and you set the air conditioning to 70F to cool 30F down. Now compare that with the ambient temp of 40F and inside cabin temp also 40F, and you again set the heat to 70F to warm 30F up. Do you think it still takes more energy to heat than cool for the same degree differences?

 

I think I set a record for % A/C load yesterday. I just got back from a flying trip to Chicago. Had the Prime parked in my friend's hangar with about 1.6 miles of EV range left. When I drove him home from the airport, I started in EV and the temperature was well over 90. I went about a mile in EV through the small city next to the airport and then switched to HV. At that point the A/C load was 41%. Combination of low speed and high temperatures.

 

I think your high A/C load ratio is mainly due to the very small amount of traction battery SOC left for that day. If you had only 1.6 miles of EV left, the ratio for the amount of battery charge used for A/C during the short trip would be high. If you had a full charge to start a day, the ratio would have been low.

 

Interesting theory, but I'm convinced that it's the ratio of A/C energy used that day vs total electrical energy used that day. That percentage was taken at the moment I hit the HV/EV button to go to HV mode. I used VERY little electricity powering the car on city streets at 30-35 mph for about a mile, compared to getting the cabin temperature down from 92 to 77 degrees.

 

Yes, but it is the ratio of A/C energy used that day vs total electrical energy used that day in EV MODE. If you have only 1.6 miles of EV MODE, the total electrical energy used that day in EV MODE is very small thus even moderate A/C energy use will cause much higher A/C ratio. I have plenty of records from my Eco Diary that shows over 50% AC load, sometimes close to 100% when I did not drive the car but turned on the car middle of winter or middle of a hot summer day. The car comes on as default EV mode, and I have AC set at 70F AUTO and use traction battery to warm or cool the cabin immediately upon turning on the car READY. If I don't drive the car at all and shut down the car 1 min later for that day, I get 0 miles driven, Average 0 mpg, Ave miles/kWh of 0.0, but have 69% AC load ratio. In line with this, if you have zero EV range on a day and you do all of driving on HV, even if you blast your car to heat or cool all day long while driving HV, you will get 0% AC load ratio for that day. I also have plenty of those days when I do not charge my car and run only HV.

 

I didn't look at it when I got home (end of the day), but just saw the 41% or something like that after the first maybe five minutes to go that first mile in EV. I guess I can look at it next time I start the car, but it wasn't the point.

I get it about ev mode. On our vacation trip, even though we used A/C or heat every day, since we weren't running in EV mode I think the A/C % was zero on those days.

So, it's not a perfect metric for determining how hard the A/C is working, but it does give an indication as long as you take into account how hard MG1 and MG2 are working, too. If it was 40% at highway speeds, that would be pretty amazing. 40% at 30 mph on a hot day while cooling the cabin, not so amazing.

Edit to add: nice clarification on the EV mode, @Salamander_King. That was my assumption, but I didn't spell it out.