371 Wh/km (600 Wh/Mile) consumption in the deep freeze

[XPsionic]

Regen does nothing for range. Same roads, same weather with regen low there is no difference at all in wh/mi. I’ve done a bunch of tests same drives.

Do you use physical brakes at all on the drives with regen set to low? I don't think you'll notice any difference in wh/mi unless you're using more disc brakes, thus converting potential energy into heat.

At some pint there was an update that greatly increased the amount of “battery conditioning”

I'd imagine that's for battery longevity and stable voltage and not only potential supercharging performance. https://www.sciencedirect.com/science/article/abs/pii/S0378775302006183

"Generally, both energy and power of the Li-ion batteries are substantially reduced as the temperature falls to below −10 °C. It has been reported that at −40 °C a commercial 18650 Li-ion battery only delivered 5% of energy density and 1.25% of power density, as compared to the values obtained at 20 °C [6]. In addition, significant differences in the cycling performance has been observed. At low temperatures, a Li-ion battery can be normally discharged, while the reverse charging process is rather difficult"

 

[coleAK]

Do you use physical brakes at all on the drives with regen set to low? I don't think you'll notice any difference in wh/mi unless you're using more disc brakes, thus converting potential energy into heat.


I'd imagine that's for battery longevity and stable voltage and not only potential supercharging performance. https://www.sciencedirect.com/science/article/abs/pii/S0378775302006183

"Generally, both energy and power of the Li-ion batteries are substantially reduced as the temperature falls to below −10 °C. It has been reported that at −40 °C a commercial 18650 Li-ion battery only delivered 5% of energy density and 1.25% of power density, as compared to the values obtained at 20 °C [6]. In addition, significant differences in the cycling performance has been observed. At low temperatures, a Li-ion battery can be normally discharged, while the reverse charging process is rather difficult"

Yes regen is more efficient than using the brakes but there is a general misconception that it converts a large % of KE back to PE.

In general and especially on (slick) winter roads I try and drive in a way where I don’t need to use my brakes much, even in my ICEs.

I’ve done a bunch of test runs from my house to town and back ~1000 vertical feet over just under 7 miles. With cruise control regen low vs regular there is no difference. Without cruise I get better wh/mi with regen low. Why? I can better more consistently maintain me speed vs over regen then accelerate then regen,…. I’ve done it where I use no regen at all on the way down (and allow myself to speed) and get lower wh/mi then regen high where I regen but then have to use power when needed. In the summer Going downhill I get around -70 wh/mi and use 0% some days but going up the hill I average ~650 wh/mi and use 4-5%.

From what I can tell full power regen is at best 15-20% efficient at capturing back energy. That is when going down long hills. Daily driving on flat ground probably <5%.

 

[XPsionic]

Yes regen is more efficient than using the brakes but there is a general misconception that it converts a large % of KE back to PE.

In general and especially on (slick) winter roads I try and drive in a way where I don’t need to use my brakes much, even in my ICEs.

I’ve done a bunch of test runs from my house to town and back ~1000 vertical feet over just under 7 miles. With cruise control regen low vs regular there is no difference. Without cruise I get better wh/mi with regen low. Why? I can better more consistently maintain me speed vs over regen then accelerate then regen,…. I’ve done it where I use no regen at all on the way down (and allow myself to speed) and get lower wh/mi then regen high where I regen but then have to use power when needed. In the summer Going downhill I get around -70 wh/mi and use 0% some days but going up the hill I average ~650 wh/mi and use 4-5%.

From what I can tell full power regen is at best 15-20% efficient at capturing back energy. That is when going down long hills. Daily driving on flat ground probably <5%.

Well if you want to read more about how regen actually works here's a good link:

https://www.tesla.com/blog/magic-tesla-roadster-regenerative-braking

Your numbers and hunches are way off, and as you described, you almost never use physical brakes so that's the reason why changing regen modes seem to change nothing for your efficiency.

 

[coleAK]

Well if you want to read more about how regen actually works here's a good link:

https://www.tesla.com/blog/magic-tesla-roadster-regenerative-braking

Your numbers and hunches are way off, and as you described, you almost never use physical brakes so that's the reason why changing regen modes seem to change nothing for your efficiency.

Well the blog you referenced is all theoretical. I’ve calculated it all out before and had it at max ~50% efficient, so max 64% isn’t that far off. Most of the time even going down my long hill my regen bar is at ~20-30%. To put that into reference 20% regen is a 12.8% return on your PE investment. Half strength regen is getting you 32% back. So when your regen bar is hovering in the bottom 10% you are gaining back ~6% of the KE you spent.

In the summer When I go down my hill with regen to full, cruise control set turn around and go straight back up. Best day of the year I get ~300 wh/mi. That gets me ~12% regen return, which is right in line with the efficiency Tesla claims in the blog you referenced.

Think about it. If regen was 100% efficient a Tesla going up and down would be a perpetual motion machine and my net would be ~0 wh/mi. Or you could tow a tesla with another Tesla under full regen and just swap and never have to charge. I’d use 650 wh/mi going up and capture -650 wh/mi going down. If it were closer to 50% effective I would use 650 wh/mi going up and -325 wh/mi going down for a 162.5 wh/mi round trip. To get a net rated range it would have to be 23% efficient in order for me to get rated range. (650+ (-650*0.23))/2 = 250 wh/mi.


No one gets close to rated range driving in the mountains. It’s more like a 20-30% reduction.

 

[XPsionic]

Most of the time even going down my long hill my regen bar is at ~20-30%

You're mistaken about a few concepts. First of all, the regen bar at 20% doesn't mean it's 20% efficient, it means it's generating 20% of maximum regen potential, which is somewhere around 75kw

https://www.reddit.com/r/teslamotors/comments/b4q8lx

If regen was 100% efficient a Tesla going up and down would be a perpetual motion machine and my net would be ~0 wh/mi.

Of course your car will still use up energy to overcome rolling resistance, air drag, and accessories usage. In fact regen in a heavy vehicle can indeed recouperate well over 80% of the energy used, check the graph for the Tesla semi going up and down a giant hill here and seemingly "flattened a hill" in terms of energy usage:

https://www.reddit.com/r/teslamotors/comments/zce6b7

~300 wh/mi. That gets me ~12% regen return

You're confusing the terms "regenerative braking efficiency" with "% miles added". The efficiencies of regen by itself is somewhere around 80%. The overall % change in range added is highly dependent on the type of terrain, traffic, and ambient conditions. If you drive straight on a highway without ever stopping you would have 0% range added, but that doesn't change the fact that your car still can achieve 80% "regenerative braking efficiency". If you drive extremely slowly in stop and go traffic with no AC on, using regen to slow down vs absolutely zero regen and using physical brakes instead, you would easily see a almost doubling of overall range.

 

[coleAK]

You're mistaken about a few concepts. First of all, the regen bar at 20% doesn't mean it's 20% efficient, it means it's generating 20% of maximum regen potential, which is somewhere around 75kw

https://www.reddit.com/r/teslamotors/comments/b4q8lx

Of course your car will still use up energy to overcome rolling resistance, air drag, and accessories usage. In fact regen in a heavy vehicle can indeed recouperate well over 80% of the energy used, check the graph for the Tesla semi going up and down a giant hill here and seemingly "flattened a hill" in terms of energy usage:

https://www.reddit.com/r/teslamotors/comments/zce6b7

You're confusing the terms "regenerative braking efficiency" with "% miles added". The efficiencies of regen by itself is somewhere around 80%. The overall % change in range added is highly dependent on the type of terrain, traffic, and ambient conditions. If you drive straight on a highway without ever stopping you would have 0% range added, but that doesn't change the fact that your car still can achieve 80% "regenerative braking efficiency". If you drive extremely slowly in stop and go traffic with no AC on, using regen to slow down vs absolutely zero regen and using physical brakes instead, you would easily see a almost doubling of overall range.

Not close to accurate. Do you own a Tesla? And you are quoting Reddit…. What is next Wikipedia?

Well now another one on my ignore list.

 

[vogz]

Not close to accurate. Do you own a Tesla? And you are quoting Reddit…. What is next Wikipedia?

Well now another one on my ignore list.

So you don't refute anything said, but instead poke fun at reference links and then put someone on your ignore list because they disagree with your assertions? Jeez

I fully expect to end up on "ignore" too.

 

[Brewmyown]

No regen at all, and this is one of the things that seems to have changed (for the better). In paster winters the heat pump would work super hard to keep the cabin warm and warm the battery. Now if I start my journey with regen (preconditioned in my garage which isn't heated but is a lot warmer than ambient) that regen will disappear as I am driving. I think it's no longer spending the energy to keep the battery warm enough for regen which is the right call. You would spend way more power to keep the battery warm enough to grab a couple of kWh when stopping.

None of this is in any patch notes of course. It's just what I've experienced over 3 winters. In the past, it feels like the heat pump was working harder and I would get more regen as I was driving. Now it seems like the compressor is working a bit less and I am losing battery temp, which is again I think the right decision here.

Are you saying you lost or had reduced full regen as you were driving in cold temps? I drive about 35 miles each way to work and when the temperatures here in the far northwestern suburbs of Chicago were about -10 F to -14 F, I never lost any regen on the trips to the office at around 5:00 AM or home at around 4:00 pm.

 

[vogz]

Are you saying you lost or had reduced full regen as you were driving in cold temps? I drive about 35 miles each way to work and when the temperatures here in the far northwestern suburbs of Chicago were about -10 F to -14 F, I never lost any regen on the trips to the office at around 5:00 AM or home at around 4:00 pm.

I'm really surprised you didn't lose any regen at all last week. I have a 7 mile commute (obviously less than you), but I also have a heated garage and pre-conditioned for 20+ mins before leaving in the mornings and by the time I was driving home in the early afternoon I had absolutely zero regen for the whole drive home and acceleration was nerfed a bunch too. I did pre-condition in the parking lot at work for about 15 mins before heading home each day too.

 

[Brewmyown]

I'm really surprised you didn't lose any regen at all last week. I have a 7 mile commute (obviously less than you), but I also have a heated garage and pre-conditioned for 20+ mins before leaving in the mornings and by the time I was driving home in the early afternoon I had absolutely zero regen for the whole drive home and acceleration was nerfed a bunch too. I did pre-condition in the parking lot at work for about 15 mins before heading home each day too.

I have a heated garage (Kept at 50 degrees) and I use the scheduled departure setting. I tend to leave just after getting an alert that the car reached the desired temperature. I have driven the car every day (unfortunately there have been several over the last week or so) that it's been below zero and have never experienced any reduced or lost regenerative braking. I have a tesla wall charger at home, and I will usually plug into a normal 120 V 15-amp outlet outside at work. On some of those below zero days, the app indicated the battery was just warming and no charge was added all day (about 9-10 hours). It typically gets 4 and sometimes 5 miles per hour added while at work. I always use scheduled departure from work to home and home to work.

 

[vogz]

I have a heated garage (Kept at 50 degrees) and I use the scheduled departure setting. I tend to leave just after getting an alert that the car reached the desired temperature. I have driven the car every day (unfortunately there have been several over the last week or so) that it's been below zero and have never experienced any reduced or lost regenerative braking. I have a tesla wall charger at home, and I will usually plug into a normal 120 V 15-amp outlet outside at work. On some of those below zero days, the app indicated the battery was just warming and no charge was added all day (about 9-10 hours). It typically gets 4 and sometimes 5 miles per hour added while at work. I always use scheduled departure from work to home and home to work.

Ah, there you go. You plug in at work and it keeps the battery warm. My car just sits for 8-10 hours in the cold parking lot.

 

[Brewmyown]

Ah, there you go. You plug in at work and it keeps the battery warm. My car just sits for 8-10 hours in the cold parking lot.

 

[coleAK]

So you don't refute anything said, but instead poke fun at reference links and then put someone on your ignore list because they disagree with your assertions? Jeez

I fully expect to end up on "ignore" too.

I presented real world data from my 6 winters and experience in a model 3. Total I have 9 years in two teslas (had a model s before the 3) in the winter and driving up and down this hill. I also have a 3rd Tesla (2023 SR 3) at one of my other homes.

Then they quoted Reddit, which isn’t a reliable reference so there is no point in referencing it. Where was their real world data? None. And why were they adding input on a thread about the deep cold when they are in SoCal? You don’t see me posing about range lost in the heat, Between AK and HI I never see temps over about 82F. Or supercharging (as I’ve only done it 4 or 5 times).

So from my perspective we have someone that most likely doesn’t own a model 3. If they do they haven’t done any of their own work driving up and down hills (a bunch of times) and looking at their numbers. And do not know the difference between reliable and unreliable sources of information. With around 7 years on this forum now I don’t have time for that. Ignored.

I’m happy to have discussions, look at what I posted above, I try and keep it to personal experience (with data to back it up).

 

[Brewmyown]

Vogz:
I just spoke to my business partner who has had a 2020 since new and he experiences the same thing as you but his car does not have a heat pump. I see yours is a 2020. Some 2020 cars had them depending on the manufacturing date. I have left it out in sub-zero temps for a few hours and never had it happen.

 

[coleAK]

I'm really surprised you didn't lose any regen at all last week. I have a 7 mile commute (obviously less than you), but I also have a heated garage and pre-conditioned for 20+ mins before leaving in the mornings and by the time I was driving home in the early afternoon I had absolutely zero regen for the whole drive home and acceleration was nerfed a bunch too. I did pre-condition in the parking lot at work for about 15 mins before heading home each day too.

I also have a heated (radiant in floor) garage (set to 55F). I have ~50% regen at best when I leave for work. I’m 7 miles away and when it’s -20F to -40F I see no regen at all by the time I get to work. I also plug into 110 when at work (Alaska has a ton of them in lots for block heaters). And have almost no regen at all when it’s <0F. I do not pre heat before I leave my heated garage but I do before I come home while plugged into the 110.

So my experience with my 2018 (and the experience of the dozen or so buddies I work with that also have teslas) is in line with yours.

I don’t see “full regen” from a “cold start” until temps are pushing 70F.

 

[dakhlkt22]

I also plug into 110 when at work (Alaska has a ton of them in lots for block heaters).

Neat. Are these all typically installed in the parking spaces of private businesses where they can directly control who uses the parking space? Or you're saying these just have 110V outlets even in public parking areas like grocery store parking lots.

So interesting to hear the AK charging experience. I was just up there for a vacation and it was interesting to see the geography of the state. The cities and towns are really far apart from each other and it's mostly just wilderness in between. We passed some houses with pontoon planes parked in their backyards. At the Mendenhall glacier, I was really surprised to see 8-10 EVs (half Bolts, half Teslas) in the parking lot.

 

[coleAK]

Neat. Are these all typically installed in the parking spaces of private businesses where they can directly control who uses the parking space? Or you're saying these just have 110V outlets even in public parking areas like grocery store parking lots.

So interesting to hear the AK charging experience. I was just up there for a vacation and it was interesting to see the geography of the state. The cities and towns are really far apart from each other and it's mostly just wilderness in between. We passed some houses with pontoon planes parked in their backyards. At the Mendenhall glacier, I was really surprised to see 8-10 EVs (half Bolts, half Teslas) in the parking lot.

I’m guessing you were on a cruise? Juneau has a ton of EVs. It’s sort of the perfect place for one. Temperate climate (relatively) only ~30 miles of roads.

You are correct we have a ton of nothingness up here. Where we caribou hunt it is 800 miles one way. The last 750 miles I pass five gas stations and two fast food restaurants. We got our first superchargers in the state 1 year ago. Now we have ~12 locations (most are CCS, 2 are is Tesla) about one every 150-200 miles. None north of Fairbanks. To put that into perspective AK is almost as large as the entire lower 48. It would cover Miami to Canada and out to Las Vegas. With 12 super chargers, 3 acute care hospitals, and just over 700k people.

As for block heaters. With block heaters It only makes sense to plug in if you are going to be there for a while. Many employee parking lots have them. Other places like airport lots, Schools, hotels,… have them.

We have very few roads. There are more listened pilots in AK then drivers. Only ~15% of our communities are accessible via road.

The farthest West Point in the state you can drive to is here on the red pin.

 

[coleAK]

Here are some pictures of my daily commute today.

Left the garage, scheduled my charge to end when I left. I keep my heat set to 65F auto. 54F I had ~ 80% of the regen bar. Made it to work 7 miles later and down ~1000 ft at -11F Had less regen, 245 wh/mi for the trip and 57%. Plugged into the 110. Only had to go in for 4 hours, so battery probably wasn’t completely cold. Pre heated to 65F, left when it let me know cabin was to temp. -1F, about 1/3 regen 53%. Made it home 7miles later up the hill, -1F >half regen, 46% and 596 wh/mi for the trip.

 

[dakhlkt22]

You are correct we have a ton of nothingness up here. Where we caribou hunt it is 800 miles one way. The last 750 miles I pass five gas stations and two fast food restaurants. We got our first superchargers in the state 1 year ago. Now we have ~12 locations (most are CCS, 2 are is Tesla) about one every 150-200 miles. None north of Fairbanks. To put that into perspective AK is almost as large as the entire lower 48. It would cover Miami to Canada and out to Las Vegas. With 12 super chargers, 3 acute care hospitals, and just over 700k people.

Wow, I knew AK was big but didn't quite realize how big. 800 miles is NYC to Chicago!

I guess if those gas stations are commercially viable, they could eventually add charging in some of those remote locations assuming there is already enough electricity from electrical transmission lines that run to those areas.

As for block heaters. With block heaters It only makes sense to plug in if you are going to be there for a while. Many employee parking lots have them. Other places like airport lots, Schools, hotels,… have them.

Very interesting setup. Sounds like they give the electricity away for free now. I wonder how much electricity a block heater uses compared to an EV keeping the battery preconditioned.

The farthest West Point in the state you can drive to is here on the red pin.

Dang! AK is truly the frontier.

 

[coleAK]

Very interesting setup. Sounds like they give the electricity away for free now. I wonder how much electricity a block heater uses compared to an EV keeping the battery preconditioned.


Dang! AK is truly the frontier.

My block heater+battery warmer draws ~800w, so a little less then 1/2 what my model 3 draws.

It’s great you got to experience AK!