Wow, we need to find another way to heat EVs

[marco33]

SR+ 90 mile trip. Temps below freezing

First road trip - ok, mini road trip. I was expecting some range loss but was surprised by almost 50%. 77 of the 90 miles was on the highway so not sure of the impact of cruising at 77.

Way out - day: 27 degrees, sun shining
Charged to 230 miles, little over 90%. Got there with 93 miles left, about 37%. Used about 140 of range to go 90 miles.

Way back - night: 22 deg car cooooold
Level 2 charged to 188. Energy graph said I would get home with 11%, actual was 14%, so did not need to spare the heat, radio or speed.

The trip worked as the level two was close and I had 3+ hours before my return. Also had a super charger 20 min away. If I wanted to leave after an hour, not sure I could make that work in the winter time With just the level 2. Will do the trip again in spring and summer, will be interesting to see the differences

Car drove great, fun ride!

but heating is a range killer. More than I expected. I think we might need better solutions or bigger batteries. Can’t wait for battery day.

 

[WilliamG]

Added complexity or otherwise, a heat pump would mitigate this issue to a significant degree (pun intended).

 

[jjrandorin]

SR+ 90 mile trip. Temps below freezing

First road trip - ok, mini road trip. I was expecting some range loss but was surprised by almost 50%. 77 of the 90 miles was on the highway so not sure of the impact of cruising at 77.

Way out - day: 27 degrees, sun shining
Charged to 230 miles, little over 90%. Got there with 93 miles left, about 37%. Used about 140 of range to go 90 miles.

Way back - night: 22 deg car cooooold
Level 2 charged to 188. Energy graph said I would get home with 11%, actual was 14%, so did not need to spare the heat, radio or speed.

The trip worked as the level two was close and I had 3+ hours before my return. Also had a super charger 20 min away. If I wanted to leave after an hour, not sure I could make that work in the winter time With just the level 2. Will do the trip again in spring and summer, will be interesting to see the differences

Car drove great, fun ride!

but heating is a range killer. More than I expected. I think we might need better solutions or bigger batteries. Can’t wait for battery day.

Huuuuuggggeeeeee impact at "cruising at 77". Its not linear power usage its more like exponential. "cruising at 60" is much much much much (much much much much) more efficient, from a power usage, not counting heat. It will take you longer to get there going 60 than 77 so not sure how that math works out, but people really discount the effect speed has on range, and it is HUUUUUGGGGGGGEEEEEEEEEEEEEEEEEEE

 

[PACEMD]

Cold and speed are the big range killers. Of those, speed is the only factor you can control. Discounting temperature, at 55 mph I get full range, above 65 mph efficiency drops off rapidly. 65 mph is a good compromise of time and efficiency. The effect of speed is exaggerated with temperatures below 20f or so. Meaning if you are worried about range, especially in the cold, slow down. Some folks obsess about cabin temperature, personally I think that effect is minimal, and certainly not as efficiency consuming as speed when it's cold. Meaning you're better off to drive warm but slow down. I'm talking about highway range driving. Start and stop, parking in the cold, starting again, stopping, parking, blah blah blah in winter is a different issue.

 

[Teedub21]

Did my longest drive to date a week or so ago in my SR+. Temps in the 40's. Left with 84% charge. Drove 80 miles round trip averaging 75 mph. Car did sit and cool back down for a couple hours before the return trip. Got home with 26% battery remaining. HVAC and speed eats the range.

 

[mswlogo]

I think we might need better solutions or bigger batteries. Can’t wait for battery day.

But you opt'd to pass on the bigger battery, right?

 

[ewoodrick]

SR+ 90 mile trip. Temps below freezing

First road trip - ok, mini road trip. I was expecting some range loss but was surprised by almost 50%. 77 of the 90 miles was on the highway so not sure of the impact of cruising at 77.

Way out - day: 27 degrees, sun shining
Charged to 230 miles, little over 90%. Got there with 93 miles left, about 37%. Used about 140 of range to go 90 miles.

Way back - night: 22 deg car cooooold
Level 2 charged to 188. Energy graph said I would get home with 11%, actual was 14%, so did not need to spare the heat, radio or speed.

The trip worked as the level two was close and I had 3+ hours before my return. Also had a super charger 20 min away. If I wanted to leave after an hour, not sure I could make that work in the winter time With just the level 2. Will do the trip again in spring and summer, will be interesting to see the differences

Car drove great, fun ride!

but heating is a range killer. More than I expected. I think we might need better solutions or bigger batteries. Can’t wait for battery day.

Yep, it's in the right neighborhood. I start at about 30% degradation for cooler temps. Maybe a little more for your temps. Drive it at 77 mph, that's another 10% or so.

Just slow it down a little and life will be much better. Summer time will be much better.
And ALWAYS charge to 100% when going on a trip. No need not to.

But, remember, even in those conditions, you made it.

 

[RDoc]

A diesel fueled heater for the cabin and battery similar to the ones used in planes and boats would be great with a small fuel tank. Lots of heat and less CO2 emissions than using the battery in almost all cases.

 

[bruce4000]

Yeah, drag/ air resistance goes up with the square of speed so becomes the most important factor at highway speeds. One reason Tesla is has the most efficient Evs because they put aerodynamics first while traditional ice puts looks/ marketing first. You can get away with it with gas but not evs

 

[67King]

Drag is a funtion of:
Drag coefficient
Frontal area
Air density
The SQUARE of velocity.

In other words, drag goes up exponentially with speed. Drag at 80MPH is four times greater than it is at 40MPH. As stated above, you can control teh speed, that will help.

That said, the cold KILLS range. I just did a similar trip. Summer, no problem on a round trip to Chattanooga from Knoxville. In the winter, even though I put on "range" wheels and tires, I could not. Had to stop and recharge on teh way home. Drove 77-78, but it was 21-23 degrees during the trip in the morning.

 

[OlderThanDirt]

Those temps are downright balmy where we live and travel..... And we go anywhere, anytime. in any temp... with heat..

I'm curious what your trip consumption on the energy screen was showing you?? Wind speed and direction was??

 

[Gwgan]

Don’t forget the sneaky headwind. 10mph doesn’t seem like much when standing outside a parked car but add 10 to 77 and the impact is huge.
I check in with Tesla Winds and Elevation Web Browser App (when my Model X MCU1 browser is working) on highway trips.

 

[OCR1]

When I see people ordering an SR+ because they want FSD and don’t have the budget for a LR AWD car with FSD, I need to send them a link to this post as a reminder of how valuable the larger battery can be when it’s cold out and you still want to drive fast.

 

[Black306]

Huuuuuggggeeeeee impact at "cruising at 77". Its not linear power usage its more like exponential. "cruising at 60" is much much much much (much much much much) more efficient, from a power usage, not counting heat. It will take you longer to get there going 60 than 77 so not sure how that math works out, but people really discount the effect speed has on range, and it is HUUUUUGGGGGGGEEEEEEEEEEEEEEEEEEE

Yup. Found out the hard way. Did a ~266 mile trip (each way). I was getting closer to 200 on a charge than the rated 299 when cruising around 77.

 

[ralph142]

A diesel fueled heater for the cabin and battery similar to the ones used in planes and boats would be great with a small fuel tank. Lots of heat and less CO2 emissions than using the battery in almost all cases.

easy enough to add an espar or the cheap Chinese version if you like. But less co2 than the battery? Figure 1500 watts an hr, vs 1/10th gallon of diesel per hr once things are warmed up. Guessing no on the less co2, plus, of course the whole no petro ethic is gone.

 

[marco33]

Good question about kWh. Wish I copied that down. I kind of remember it being in the high 300, maybe 377. But not sure.

I am happy with my SR+ range choice. The car is mostly for day to day, around town, work and into philly etc. 250 is plenty (good compromise). I make this 90 mile trip maybe three times a year. I’m pretty much covered by the level two charger or the super charger that’s 20 minutes away. And if that becomes inconvenient I can always ice it.

I am interested in the speed impact. Might try it at 65 next time to see the difference.

 

[Msjulie]

Added complexity or otherwise, a heat pump would mitigate this issue to a significant degree (pun intended).

I agree, even w/o the pun

Maybe the efficiency of these will improve enough to make it worth it. I mean the AC is already a heat pump, don't know how much it takes to 'reverse' where it sends the heat

Can heat pumps solve cold-weather range loss for EVs?

 

[jpfive]

Yup. Found out the hard way. Did a ~266 mile trip (each way). I was getting closer to 200 on a charge than the rated 299 when cruising around 77.

My exact experience from Pensacola - Tallahassee. 200 mile trip. Glad I bought the LR. I cruise at 73 usually, but on the occasions that I am slowly overtaking, especially stacked semis in the right lane, I speed up to expedite getting around. With 90SOC I make the Tallahassee superchargers with room to spare. I remember a chart - somewhere on this forum, or a link - that illustrates rated range coinciding with 60-65 mph. Driving that speed is not relaxing on the Interstate. Keeps me glued to my rear view mirror.

 

[thors_hammer]

Just a slight variation on what everyone is saying--it's not cold that affects range, but rather a cold battery. You'll get closer to the rated range if you leave right after charging is finished (and avoid speed and the heater). Until it gets down to about 25F or less, I'm getting close to summer range by following these guidelines. Below those temps, it seems the battery eventually cools from driving at highway speeds and the car needs to spend some energy warming it back up. Still, nowhere near 50%+ additional power used.

 

[jpfive]

Regarding heat, I have seen more than one thread here making the argument for seat heaters rather than forced air. Claim is that they are a more efficient method for heating, and quite effective. OP's from northern climes. Now, about that heated steering wheel we don't have...