Winter Driving Experiences

[neroden]

Hmm. So I'm trying to summarize the things I need to remember (i.e. things which aren't the same as average RWD ICE cars) from various reports:

(1) The retrofit for the ventilation ducts so that the windshield will be defogged/deiced seems to be essential and should be gotten ASAP.
(2) In the winter, we need winter wiper blades.
(3) For snow tires in terrible conditions, Tesla's recommended Pirelli snow tires are not ideal. (What was the most common recommendation -- Nokian Hakkapeliitta something?)
(4) Reliable range drops about 20% when below roughly 0C (32F) and drops about 30% when below -20C (-4F).
(5) There is a certain amount of "invisible range" when batteries are cold-soaked.
(6) Vampire losses (~3 miles/day base) increase substantially at the same temperatures at which range drops. (Any numbers?)
(7) At slightly low temperatures, the battery heats up within less than an hour, but at very low temperatures (-20C), the battery can take a very long time to heat up.

Anything I've missed?

 

[znino]

Hmm. So I'm trying to summarize the things I need to remember (i.e. things which aren't the same as average RWD ICE cars) from various reports:

(1) The retrofit for the ventilation ducts so that the windshield will be defogged/deiced seems to be essential and should be gotten ASAP.
(2) In the winter, we need winter wiper blades.
(3) For snow tires in terrible conditions, Tesla's recommended Pirelli snow tires are not ideal. (What was the most common recommendation -- Nokian Hakkapeliitta something?)
(4) Reliable range drops about 20% when below roughly 0C (32F) and drops about 30% when below -20C (-4F).
(5) There is a certain amount of "invisible range" when batteries are cold-soaked.
(6) Vampire losses (~3 miles/day base) increase substantially at the same temperatures at which range drops. (Any numbers?)
(7) At slightly low temperatures, the battery heats up within less than an hour, but at very low temperatures (-20C), the battery can take a very long time to heat up.

Anything I've missed?

My Vampire loss from full charge is more like 1km per hour as witnessed over the first 12 hours. For you in imperial units, that's about 8 miles in the first 12 hours (might drop off after that but have not checked). And this is in an inside garage at about 60 degrees.

 

[hershey101]

Hmm. So I'm trying to summarize the things I need to remember (i.e. things which aren't the same as average RWD ICE cars) from various reports:

(1) The retrofit for the ventilation ducts so that the windshield will be defogged/deiced seems to be essential and should be gotten ASAP.

Anything I've missed?

Can you describe what you mean by retrofit for the ventailation ducts? Is there no front and rear defroster in the car like most other cars/does it not function well?

 

[Al Sherman]

Fogging

 

[Doug_G]

Hmm. So I'm trying to summarize the things I need to remember (i.e. things which aren't the same as average RWD ICE cars) from various reports:

(1) The retrofit for the ventilation ducts so that the windshield will be defogged/deiced seems to be essential and should be gotten ASAP.
(2) In the winter, we need winter wiper blades.
(3) For snow tires in terrible conditions, Tesla's recommended Pirelli snow tires are not ideal. (What was the most common recommendation -- Nokian Hakkapeliitta something?)
(4) Reliable range drops about 20% when below roughly 0C (32F) and drops about 30% when below -20C (-4F).
(5) There is a certain amount of "invisible range" when batteries are cold-soaked.
(6) Vampire losses (~3 miles/day base) increase substantially at the same temperatures at which range drops. (Any numbers?)
(7) At slightly low temperatures, the battery heats up within less than an hour, but at very low temperatures (-20C), the battery can take a very long time to heat up.

Anything I've missed?

Pretty good list, but I'm wondering if (6) is actually just another version of (5).

 

[pbrulott]

Hmm. So I'm trying to summarize the things I need to remember (i.e. things which aren't the same as average RWD ICE cars) from various reports:

(1) The retrofit for the ventilation ducts so that the windshield will be defogged/deiced seems to be essential and should be gotten ASAP.
(2) In the winter, we need winter wiper blades.
(3) For snow tires in terrible conditions, Tesla's recommended Pirelli snow tires are not ideal. (What was the most common recommendation -- Nokian Hakkapeliitta something?)
(4) Reliable range drops about 20% when below roughly 0C (32F) and drops about 30% when below -20C (-4F).
(5) There is a certain amount of "invisible range" when batteries are cold-soaked.
(6) Vampire losses (~3 miles/day base) increase substantially at the same temperatures at which range drops. (Any numbers?)
(7) At slightly low temperatures, the battery heats up within less than an hour, but at very low temperatures (-20C), the battery can take a very long time to heat up.

Anything I've missed?

Here is a wisk list summary I was trying to keep up to date. #4 has been partly solved as reported in Doug_G's post p.81 and at the time of the summary, Vampire load was resolved but with 4.2 it seems to have come back.

1 - TM propose a winter tire package (like Nokian H) not only the Pirelli tires for cold/snow weather
2 - An app/web app be introduced to heat the battery pack 30 min before leaving vs at all time the battery reaches critical temp waisting precious juice => partly solved due to the App release on both Android and iOS. Climate control and charge only though. No proof of the app heating the pack.
3 - The ventilation system be adapted for winter (cold and humidity) => In the works, to be retrofitted optionally by Service Centers via service bulletin
4 - The car could draw its power from the wall vs the pack when plugged and parked (and not charging) to stay above critical temp => possible via the App only
5 - There is a winter mode to allow for raising the Air supension permanently above 8mph
6 - The Traction Control at really low speed be tweaked to allow spinning since snow/ice driving requires some spinning
7 - A better range calculation algorithm introduced as the current one is not adequate

 

[znino]

Asked about this a little while ago but nobody answered.... Has anyone replaced their wipers with Winter blades? Where did you get them? Specific brand, size etc? Thanks

 

[PatP]

Asked about this a little while ago but nobody answered.... Has anyone replaced their wipers with Winter blades? Where did you get them? Specific brand, size etc? Thanks

I've been thinking about doing it. It seems the size are the following (according to TireRack.com):

• 17" Passenger side wiper.
• 26" Driver side wiper.

 

[RDoc]

Pretty good list, but I'm wondering if (6) is actually just another version of (5).

Aren't there two effects on the battery in cold weather?

a) The battery must be maintained above freezing overnight to avoid permanent damage which obviously takes power.
b) At low temp the battery capacity is less, and when driving in cold temps and/or rain etc., the battery may need to be heated to keep it at max capacity.

 

[EV-EN]

http://www.webasto.com/int/markets-products/car/retrofit-parking-heater/Hi I know it has been mention before and might not be political correct, but a small compromise should be possible.
I like a fuel burner of some sort to be optional in a 'cold climate' version. This heater will preheat both cabin and battery as well as add heat when driving, this will result in same range in -20deg as +20deg (a little less due to winter tires Nokian Hakka and if snow)
Webasto has a nice solution for ICE. http://www.webasto.com/fileadmin/webasto_files/documents/international/car/brochure/car-parking-heater-brochure.pdf
One might be able to install it later, should fit in the Frunk together with a small fuel tank, but it's of course preferable done original from Tesla. A fuel heater is a must for comfort and range. Due belive this is more important for most drivers than i.e awd.

 

[nikwest]

Wouldn't also a layer of some kind of insulation material below the battery pack be of some help to keep the batteries warm? It's a pretty big area and there most be a significant heat loss

 

[wycolo]

Wouldn't also a layer of some kind of insulation material below the battery pack be of some help to keep the batteries warm? It's a pretty big area and there most be a significant heat loss

Insulating spray as used on steel shipping containers is routinely applied 2 inches thick. That would certainly be a plus on the S bottom surface. And if you scraped some off during off-road operation you could easily build it back up using a can of spray foam sealant.
--

 

[pbrulott]

Aren't there two effects on the battery in cold weather?

a) The battery must be maintained above freezing overnight to avoid permanent damage which obviously takes power.
b) At low temp the battery capacity is less, and when driving in cold temps and/or rain etc., the battery may need to be heated to keep it at max capacity.

When parked and not plugged, and the critical temperature of the pack is reached (from various report it seems to be in the -20 to -26 celsius), only at that time that the heater will enter into function and lose precious energy. TM write in its warranty doc that leaving the car unplugged for more than 24h at below -30C will void the warranty. So no damages foreseen when in below freezing until very very cold.

TM technical support mentioned to me that Model S' pack doesn't inherently lose range (not true since sleep mode has been disabled with 4.2 but nomral behavior is expected to come back with new firmware version). Accordingly, when in cold temp (but above critical temp), the perceived loss of range is not entirely real and is overestimated using the current algorithm. What he said what that the lost range should come back as the back raises in temperature and regen is enabled. Some posters have reported not seeing the miles come back though edit: or what would appear to be slower fall in range than you'd expect


@ nickwest

a member from Norway has written a post on a thin insulating sheet that could be added underneath the car. you can scan the previous pages to discover the material he referred too. that was pretty inovative.

 

[Doug_G]

Some posters have reported not seeing the miles come back though...

If you're using the miles at the time, you may not see the number actually rise; however, it will fall slower than you'd expect.

 

[pbrulott]

Right Doug, well said, miles are consumed as you go so a slower fall is likely

 

[eledille]

@ nickwest

a member from Norway has written a post on a thin insulating sheet that could be added underneath the car. you can scan the previous pages to discover the material he referred too. that was pretty inovative.

That was me, but in another thread, also about winter driving

 

[Mayhemm]

Wouldn't a heavily-insulated battery pack have trouble dissipating heat in the summer?

You'd trade a slight reduction in winter mileage for an increased risk of system failure due to overheating in summer.

 

[jerry33]

Wouldn't a heavily-insulated battery pack have trouble dissipating heat in the summer?

You'd trade a slight reduction in winter mileage for an increased risk of system failure due to overheating in summer.

Not necessarily, In hot areas there could be quite a bit of heat radiating from the pavement so the insulation might actually keep the battery cooler. The battery is already insulated (just not enough for the coldest conditions), and the cooling happens through the heat exchanger.

 

[neroden]

Pretty good list, but I'm wondering if (6) is actually just another version of (5).

(6), the extra energy draw below 0 F, appears to relate to the need for the battery to heat itself to avoid permanent damage the battery. (5) relates to the fact that a cold battery (but not cold to the permanent-damage point) displays lower amperage/voltage to the meters until it heats up. In short, (5) is a mere display issue, (6) is an actual energy use issue.

 

[Doug_G]

No, the battery isn't insulated. Maybe that helps in summer. They have radiators at the front to deal with heat... but probably they were sized expecting there to be heat loss through the underside of the pack. It is the major issue with heat loss in winter. Everything is a compromise.