EV's and Cold Weather

[Jim_in_Delaware]

Cybertruck tow 11,000 in freezing temps

Interesting video.

Range and lack of pull through chargers are reasons that I'm excited to see how the 2025 Ramcharger does as a comparison.

Jim

 

[BigN8]

The US government still spends significantly more money subsidizing fossil fuels than it does subsidizing EVs. Maybe I'm missing what you're referring to when you say that politicians should stay out of it. Hasn't the government pretty consistently subsidized leading edge research and progress in many industries?

Not even going to waste my time debating this or finding all the articles to support the debate.

 

[adrianp89]

Not if they were rental cars.

I rented a Model 3 from Hertz awhile back, and it was not a great rental car experience. I wouldn't be surprised if people rented a Model 3 and needed to charge thinking it would work the same as the one they got a few months ago and had no manual to use to RTFM.

Lol - I think everyone felt the same way including Hertz.

https://www.reuters.com/business/autos-transportation/hertz-sell-about-20000-evs-us-fleet-2024-01-11/

 

[HangOutdoors]

Yeah I read that about hertz. Seems like the whole EV experiment is going backwards.

 

[FSH 210 Sport]

The US government still spends significantly more money subsidizing fossil fuels than it does subsidizing EVs. Maybe I'm missing what you're referring to when you say that politicians should stay out of it. Hasn't the government pretty consistently subsidized leading edge research and progress in many industries?

Links please. My impression is the state and fed govts make a lot of money in tax revenues in excise tax and sales tax on each gallon of fuel sold. In ca for example, gasoline has a state excise tax and fed excise tax, then sales tax is calculated on top of the those two taxes..

 

[2kwik4u]

Yeah I read that about hertz. Seems like the whole EV experiment is going backwards.

Backwards paints a picture of failure and a waste of time/effort. I don't think that's the case. We're learning what works and what doesn't. Some successes, some failures, some mixed results.

 

[CaptRedbeard]

Links please. My impression is the state and fed govts make a lot of money in tax revenues in excise tax and sales tax on each gallon of fuel sold. In ca for example, gasoline has a state excise tax and fed excise tax, then sales tax is calculated on top of the those two taxes..

US Energy Information Administration report:

https://www.eia.gov/analysis/requests/subsidy/pdf/subsidy.pdf

In more lay terms:

Low-Energy Fridays: How Much Are We Really Subsidizing Fossil Fuels? - R Street Institute

One surprisingly common notion is that fossil fuels are heavily subsidized in America and that renewable energy subsidies only put them on par with fossil fuels. This is a great example of how oft-repeated narratives can take on a life of their own, irrespective of reality. With the recent...

www.rstreet.org

 

[FSH 210 Sport]

US Energy Information Administration report:

https://www.eia.gov/analysis/requests/subsidy/pdf/subsidy.pdf

In more lay terms:

Low-Energy Fridays: How Much Are We Really Subsidizing Fossil Fuels? - R Street Institute

One surprisingly common notion is that fossil fuels are heavily subsidized in America and that renewable energy subsidies only put them on par with fossil fuels. This is a great example of how oft-repeated narratives can take on a life of their own, irrespective of reality. With the recent...

www.rstreet.org

Thanks! I’ll peruse later on today..

 

[buckbuck]

Here is a Canadian who has no trouble charging his Tesla at -35C (-31F). I guess he read his manual.

 

[FSH 210 Sport]

Here is a Canadian who has no trouble charging his Tesla at -35C (-31F). I guess he read his manual.

Bravo! He RTFM.

Thanks for the vid that answered the question about whether or not the heater can be used while charging. What was not calculated in this vid was how much power the heater was taking from the charge. So lets say the heat pump takes 20Kws to run, and I don’t know but I’m going to guess the supercharger is charging at 70Kw’s so the effective charge rate is 50Kws. Same with the other chargers, might be a 62Kw charger but if your systems are consuming 20Kws to keep you warm, then the effective charge rate is 42Kws.

So what I foresee happening in the future is there being a demand rate, perhaps that is why the supercharger went to 59cents per KWh on the supercharger, notably the driver mentioned that the price had gone up, this is normal pricing in the utility world, this will of course exponentially increase the price to recharge at high rates of flow. Once you understand how the “grid” works you’d understand the reason for demand rate pricing.

So to precondition the battery at those temps it takes 40% of the power to warm the battery up enough so that it will charge oh his way to the charging station, exponentially more percentage wise will go to heating on a shorter trip. Sure looks complicated and energy intensive to charge the batter in those temps. And, he was right on the edge of the system not being able to warm the battery enough to charge on the way there, and by the time he was going home it was too cold for the system to heat the battery enough to charge, that is a death spiral for the battery.

 

[2kwik4u]

Bravo! He RTFM.

Thanks for the vid that answered the question about whether or not the heater can be used while charging. What was not calculated in this vid was how much power the heater was taking from the charge. So lets say the heat pump takes 20Kws to run, and I don’t know but I’m going to guess the supercharger is charging at 70Kw’s so the effective charge rate is 50Kws. Same with the other chargers, might be a 62Kw charger but if your systems are consuming 20Kws to keep you warm, then the effective charge rate is 42Kws.

So what I foresee happening in the future is there being a demand rate, perhaps that is why the supercharger went to 59cents per KWh on the supercharger, notably the driver mentioned that the price had gone up, this is normal pricing in the utility world, this will of course exponentially increase the price to recharge at high rates of flow. Once you understand how the “grid” works you’d understand the reason for demand rate pricing.

So to precondition the battery at those temps it takes 40% of the power to warm the battery up enough so that it will charge oh his way to the charging station, exponentially more percentage wise will go to heating on a shorter trip. Sure looks complicated and energy intensive to charge the batter in those temps. And, he was right on the edge of the system not being able to warm the battery enough to charge on the way there, and by the time he was going home it was too cold for the system to heat the battery enough to charge, that is a death spiral for the battery.

Cabin heating is NOT a large draw. We need to put that myth to bed.

20kW is likely more than is used to heat your home. That's 20,000watts. Or 83amps on a 240V circuit. I have a 2,400sq ft home with a heat pump and electric heat backup. It's a 240V circuit on a 50A breaker. That's only a 12kW circuit! Many homes run on just a 100amp service for the whole building. A second comparison is that 20kW is about 5tons of refrigeration, and is good for ~2,250sqft of home.

You're probably closer to 1-2kW for the heat pump. A 2hp motor is ~1.4kW, and should run a heat pump well suited for a vehicle. Seat heaters are close to 0.5kW for both of them running full tilt.

More likely, the added draw is from cold bearings and cold gearcase fluids. Then the added resistance from pulling high current through cold conductors, contacts, and other electronics. Also, the cold electrolytes (that's not the right word) in the battery don't transfer electrons as readily as they do when warm. So a lot of energy goes to heat the battery so it can accept a reasonable charge rate......keep in mind you can always trickle charge a battery, you just probably don't have the patience to sit and wait for it at a public charger.

 

[seanmclean]

FWIW, my 50 mile trip to work uses 13% of the battery during summer months, +/- 1% depending on how much spirited driving was done. It's increased quite linearly to 20% of the battery during winter, with significantly less spirited driving due to the summer tires. I do not precondition the battery for departure, but I think I'm going to do that for tomorrow's commute and see if makes a practical difference in utilization.

 

[FSH 210 Sport]

FWIW, my 50 mile trip to work uses 13% of the battery during summer months, +/- 1% depending on how much spirited driving was done. It's increased quite linearly to 20% of the battery during winter, with significantly less spirited driving due to the summer tires. I do not precondition the battery for departure, but I think I'm going to do that for tomorrow's commute and see if makes a practical difference in utilization.

Please let us know what you find out!

 

[2kwik4u]

@FSH 210 Sport GOt stuck in the airport and starting watching random Youtbue stuff this afternoon. Ran across this.

It's a somewhat interesting watch overall, but the thing that was really interesting was a small quote in there about power consumption to heat the battery and how it's done. He said Tesla "runs the motors", however the car was obviously stationary while heating, I suspect they control the motors such that they purposefully are pushing "against themselves" and generate heat. This can by done fairly easily by adjusting the phases on an induction motor. What's even more interesting is that he makes a short comment about "I think Tesla said they use 3.5kW per motor to generate the heat".......SO, referencing back to your calculations before, the car will consume about 7kW to generate the heat needed to condition the batteries. Beyond that, once the car did warm itself, it immediate jumped to 25kW of input. So quite easily overcoming the amount needed to maintain the battery temp. Once he got there, it charged acceptably all the way up to, I think, 90%.

So, the problem isn't really that they don't charge in the cold, it's that they don't "conveniently charge quickly" in the cold. It took him about 2hrs to fully charge the car. Far longer than even a painfully slow gas pump. But he still got it done.

Just some more food for thought.

 

[Julian]

I did a little research looking to see if the Tesla has mitigation strategies for cold weather ops, and not surprisingly Tesla does, especially for charging, they call it pre conditioning, this requires energy from the battery to heat the battery up to minimal temperature for charging and it is recommended 30-45 mins before reaching a charging station. This pre condition is also recommended before driving to keep the ECU if you will from limiting how much current flows out of the battery during acceleration, E.G. reduced performance if you don’t precondition the battery, which also warms the cabin but I’m not sure how much it warms the cabin as I can find no information on the precondition warming level in the cabin. There is a smart preconditioning setting in the car but Tesla states in the owners manual this has proven unreliable and suggests a third party app be used.

Enlightening but not at all surprisingly there are additional supercharging fees known as idle and congestion. Meaning, there are increased charging fees and financial disincentives to using a supercharger station during times of high usage. In other words it’s going to cost you to charge when everyone needs it-shocker.

View attachment 213961

Another revelation, and not surprisingly at all, is that Tesla recommends leaving the car plugged in whenever not in use, this flies in the face of many electric car advocates saying the range is good enough on electric cars that you don’t need to charge everyday. Tesla recommends leaving plugged in to keep the maximum range, and during preconditioning the power to heat the battery and the inside of the car will be drawn from the charger, again not clear on what that means exactly for the level of cabin heating during charging. This is also true during hot weather, as the ac system will draw power from the charger instead of the battery. Apparently there are other systems drawing power from the battery while parked.

There is also this little nugget. Some, (??? no idea how much? i know how far my truck goes on any level of fuel in the tank) of the stored energy is not available when the battery is too cold, and regenerative braking is disabled reducing range even further.

View attachment 213960


Tesla also recommends using the seat heaters to stay warm instead of the heat pump to conserve energy, if I remember correctly Tesla suggests bundling up to stay warm and reduce battery consumption, not for me at all.

Since the Tesla uses a heat pump to heat the car, that means in cold temperatures the heat pump becomes rather ineffectual / inefficient as the Delta T is dramatically reduced which means more power is required to heat the cabin. This same heat pump is reversed to provide cooling for the cabin, and is used to keep the battery cool in hot conditions. Driving your Tesla to Palm Springs in the summer? The AC system is going to be working very hard, consuming a lot of power, to keep the cabin cool and keep the battery cool enough for normal operation. And all of that has a an impact on range.

So after a bit of research I’m convinced that a lot of these electric cars in the cold were a victim of their owners not RTFM, (read the fucking manual) these cars need to be managed carefully (be uncomfortable while operating them in cold weather) in non optimal conditions to get them to function normally. I’m betting that had the owners RTFM, they would have preconditioned their batteries they could have used the supercharger stations as intended, but that requires planning ahead at least a hour in advance of charging their cars, provided there was enough charge in the vehicles battery to precondition the battery for charging. Who knows? Maybe there was sufficient charge in the battery when they stopped but after cold soaking the battery power was dramatically reduced and that caused a death spiral. I’m also betting that these cars left with a completely discharged battery, in those cold temperatures caused further discharge to the battery and now those batteries will either be junk or have greatly reduced capacity.

Edit: At 10° or colder weather it’s very tough to scavenge heat for the heating systems via the heat pump. So looks like you’re pretty screwed in those temps.

Either way, the cold temperatures have ; eliminated regenerative braking reducing range, the battery’s inability to use all the stored energy, the batteries surprise reduction in stored energy after it is left parked in cold temps, the environmental control systems inefficiency results in dramatically increased KWh usage to keep you warm in the car, the complexity of operating the car, and the need to use what I’m assuming is a good amount of KWh’s to precondition the battery for charging results in a big fuck you to your electric car.

Tesla Extreme Weather Considerations - How To Optimize Your Tesla Driving For Winter Months

INTRODUCTION As a Tesla owner, you may have already experienced that charging and driving your Tesla in temperatures around 32

engage.tesla.com

https://www.tesla.com/ownersmanual/modely/en_us/GUID-4F3599A1-20D9-4A49-B4A0-5261F957C096.html

https://www.tesla.com/ownersmanual/modely/en_us/GUID-F907200E-A619-4A95-A0CF-94E0D03BEBEF.html

I used the search function on Tesla’s website to see if the heater can be used while charging and got these results.

View attachment 213955

View attachment 213956

Preconditioning is something I think most new EVs now have (My Ioniq 5 does). I read an article that quoted one of these Tesla owners saying "my car normally charges in 45 minutes, now its taking HOURS" - clearly this person has a MUCH older Tesla model! New Teslas take 20-25 minutes to charge.

The cold here in NC added 5 minutes to my 20 minute charge, and I didn't turn on preconditioning!

Many of these new EV owners need to learn how to use their cars and how to charge them. Super charging is definitely getting easier as the years move on. I look forward to Tesla opening up more of their chargers.....they are sure taking their time about it (yes many are on public land-which is why they were forced to do so).

As for incentives to move to EVs....only makes sense. People hate change, so we either force it on them, or incentize the change. I love my EV!!! WAY prefer driving it over my Supercharged Audi!

 

[FSH 210 Sport]

@FSH 210 Sport GOt stuck in the airport and starting watching random Youtbue stuff this afternoon. Ran across this.

It's a somewhat interesting watch overall, but the thing that was really interesting was a small quote in there about power consumption to heat the battery and how it's done. He said Tesla "runs the motors", however the car was obviously stationary while heating, I suspect they control the motors such that they purposefully are pushing "against themselves" and generate heat. This can by done fairly easily by adjusting the phases on an induction motor. What's even more interesting is that he makes a short comment about "I think Tesla said they use 3.5kW per motor to generate the heat".......SO, referencing back to your calculations before, the car will consume about 7kW to generate the heat needed to condition the batteries. Beyond that, once the car did warm itself, it immediate jumped to 25kW of input. So quite easily overcoming the amount needed to maintain the battery temp. Once he got there, it charged acceptably all the way up to, I think, 90%.

So, the problem isn't really that they don't charge in the cold, it's that they don't "conveniently charge quickly" in the cold. It took him about 2hrs to fully charge the car. Far longer than even a painfully slow gas pump. But he still got it done.

Just some more food for thought.

Like and Informative.

If the car is all wheel drive maybe the front motors were pushing back and the rears were pushing forward? As opposed to phase shifting? I’m guessing..

 

[BigN8]

Preconditioning is something I think most new EVs now have (My Ioniq 5 does). I read an article that quoted one of these Tesla owners saying "my car normally charges in 45 minutes, now its taking HOURS" - clearly this person has a MUCH older Tesla model! New Teslas take 20-25 minutes to charge.

The cold here in NC added 5 minutes to my 20 minute charge, and I didn't turn on preconditioning!

Many of these new EV owners need to learn how to use their cars and how to charge them. Super charging is definitely getting easier as the years move on. I look forward to Tesla opening up more of their chargers.....they are sure taking their time about it (yes many are on public land-which is why they were forced to do so).

As for incentives to move to EVs....only makes sense. People hate change, so we either force it on them, or incentize the change. I love my EV!!! WAY prefer driving it over my Supercharged Audi!

“Force it on them”…. No thanks Xi Jin-Julian.

 

[Julian]

“Force it on them”…. No thanks Xi Jin-Julian.

We've forced plenty of things in the past....anti lock brakes, air bags, reverse cameras etc etc., but offering incentives is a better approach.

 

[BigN8]

We've forced plenty of things in the past....anti lock brakes, air bags, reverse cameras etc etc., but offering incentives is a better approach.

Now you're really reaching....anti lock brakes and air bags which are improvements in safety compared to entirely new form of energy to power the car. Gimmie a break dude.

 

[2kwik4u]

Now you're really reaching....anti lock brakes and air bags which are improvements in safety compared to entirely new form of energy to power the car. Gimmie a break dude.

We can't keep doing what we're doing. Sometimes free market will drive progress, sometimes regulations do. Don't act like an EV mandate (or incentives) is anything we haven't seen before. Might be a bigger than normal swing, or in an industry that isn't as commonly targeted, but it's certainly not unheard of, nor is it, IMO, a bad decision.