Road Trip Efficiency

[Daniel2022AT]

I am planning a 1300 mile trip Milwaukee to Tampa with the family. A few weeks ago, I published my recent road trip Milwaukee to Detroit which was 426 miles at 4.4 mi/kWh driving 73-74 mph. With conservative driving, how much should I expect efficiency to decrease with an extra 600 pounds?

My EA experience has been quite good, generally charging starts at 160 KW and gently declines, averaging 100 KW over a 30-35 minute charge going from roughly 30% to 85% SOC. I hope that experience holds true in the south along I-75.

 

[DeaneG]

I'm going to guess that the additional weight will make little difference - it'll increase tire losses but I think (unchanged) aero is a much bigger factor at freeway speeds.
That extra "weight" should make the trip more interesting though. If you want to travel far, travel together.

“That’s probably not an African proverb.” — African Proverb

 

[Daniel2022AT]

Good thought. OK, I want to state for the public record I am not attributing any specific weight to my wife, 2 boys, or luggage. For the record.

 

[nfsdragster]

That's really impressive, I got 3.3 on highway driving 75-80. 4 driving 70 cruise control. But when I drive local I get 4.6

 

[Daniel2022AT]

The Midwest is flat, which helps greatly, and temps near an ideal 80-85, but it is also about driving style.

 

[mtatsis]

I am planning a 1300 mile trip Milwaukee to Tampa with the family. A few weeks ago, I published my recent road trip Milwaukee to Detroit which was 426 miles at 4.4 mi/kWh driving 73-74 mph. With conservative driving, how much should I expect efficiency to decrease with an extra 600 pounds?

My EA experience has been quite good, generally charging starts at 160 KW and gently declines, averaging 100 KW over a 30-35 minute charge going from roughly 30% to 85% SOC. I hope that experience holds true in the south along I-75.

4.4 miles per KWH is amazing. I just hit over 2,000 miles on my Lucid Pure. Drove 90 miles from CT to NY in about 32 degree temps with auto heat at 75, stereo playing loud, and heated driver seat on low. Cruised with ACC at 65 on highway. Only 10 miles of local streets. Achieved 3.9 miles per KWH. Seems very difficult to achieve higher mileage. Does the cold temperature affect the mileage while driving?

 

[Adnillien]

4.4 miles per KWH is amazing. I just hit over 2,000 miles on my Lucid Pure. Drove 90 miles from CT to NY in about 32 degree temps with auto heat at 75, stereo playing loud, and heated driver seat on low. Cruised with ACC at 65 on highway. Only 10 miles of local streets. Achieved 3.9 miles per KWH. Seems very difficult to achieve higher mileage. Does the cold temperature affect the mileage while driving?

Cold temperature definitely reduces your efficiency. Seat heat is more efficient than heating the air, both will draw energy from the battery. 75 interior temperature was a big factor. In addition, the battery will also heat itself taking additional energy. 3.9 m/kWhr seems pretty good for your ambient temperature. While range is reduced in cold weather, Lucid has enough range that you can be comfortable and still travel where you want.

 

[Daniel2022AT]

I’m planning some northern Midwest winter trips 400-600 miles. Temps could be +10F to -10F. I have not seen any studies about EV cold weather efficiency below +20F. We had some mornings around 25F and I was getting 3.2 m/kWh which is 25% below my normal 4.2. What should I expect for truly frigid travel? Any best practices to keep in mind?

 

[kurious]

I'll report back here tomorrow - I'm driving over two high mountain passes here in Washington, forecast temps <20F at the early morning hours I'm going over them. 74 miles between services. My plan is to charge to 95%, keep speed <60mph (boooooh!), log the kWh/range for many future trips in all conditions. Glad it is not precipitating to add variables.

 

[Daniel2022AT]

I'll report back here tomorrow - I'm driving over two high mountain passes here in Washington, forecast temps <20F at the early morning hours I'm going over them. 74 miles between services. My plan is to charge to 95%, keep speed <60mph (boooooh!), log the kWh/range for many future trips in all conditions. Glad it is not precipitating to add variables.

Anything interesting to report?

 

[kurious]

Yes, thanks for reminder.
I started in Seattle at 70 feet above sea level, 38F temperature, 95% charge. (Air Pure AWD.)
The car predicted 175 miles range remaining at the destination.
I tried to keep my speed between 50-60mph, heated cabin to 70F, music.
I drove 175 miles over a 5,477 foot mountain pass, temps in the low 20's.
At the peak of that pass, the predicted range remaining was 103mi, 30% charge.
The last 15 miles down from the pass, regen brought the charge up to 32%, final range remaining 132mi.
The handling was excellent, all season (not winter) tires on compact snow and ice for ~40 miles.
That's 3.3 miles/kWh.
The "winter range tax" is lower than I worried it was.

 

[kurious]

Also - my destination elevation is 2,200' above sea level, 3,277 feet down from the mountain pass, and 2,130' above starting elevation.
The reverse trip will use fewer kWh for same 175 mile distance.
And I've done this trip four times now, prior three in warmer temperatures, 3.6-3.8 mi/kWh on those.

 

[Daniel2022AT]

Thank you. Encouraging. I’m still worried about sub 10F conditions.

 

[kurious]

I will definitely experience sub-10F conditions in the coming months.
The route I travel closes seasonally due to avalanches, so the longer route has an EA station about halfway (120 miles.)
I'll share here some mi/kWh & range effects as I experience them.

 

[Daniel2022AT]

Fantastic. Sounds adventurous!

In MM, WI, MI, it can be -20F or +40F any given day in Jan/Feb.

 

[Steveinarizona]

I tried to keep my speed between 50-60mph, heated cabin to 70F, music.

I think the speed was essential to the rate. Change to 70 or 80 mph and watch the rate plummet.

 

[stratus]

Thank you. Encouraging. I’m still worried about sub 10F conditions.

I drove a few days last winter with temperatures at minus 10 to minus 30 , in a GT with 19 wheels. During that time frame I got 2.2 m/kWh. Awful but not unexpected.

 

[Sandvinsd]

I did a cross country trip and back during the summer, putting about 9k miles on my GT during that time, and averaged about 3.6 miles per kW. That was not too much different from my lifetime 3.5. It was lower in the west with 110 degree temps and much higher in the mid-Atlantic.