Best way to preheat battery

[KetchupKilla]

I've noticed I get much better Regen if instead of just doing a preheat cabin, I up the battery percent a bit and start a charge. Quickly brings battery temp up. I find that doing a preheat of the cabin only brings the battery temp up a tiny bit. Any downside to this in anyone's opinion. I live in Massachusetts where it gets cold so I want to get that Regen back quickly.

 

[Akikiki]

Blow Torch. Ohhh, safely? I dunno.

 

[KetchupKilla]

You got it all wrong. Not a blowtorch. A boring company flamethrower should always be used.

 

[Sophias_dad]

I am also from Massachusetts and have some of the highest electricity rates as a result. I don't care that much if I have limited regen beyond the minor annoyance that I have to use the brake a bit more often. Its likely far cheaper to use the brakes(and lose the kinetic energy of the car as heat) than to charge a percent or two and have more regen earlier. The battery-heating component of it starting to charge the battery may well be a continuous 6kw or somesuch, to zero benefit beyond getting more regen.

Maybe my driving situation is different, and I just don't use the brake as much until I've driven several miles.

 

[KetchupKilla]

Yea electricity rates are ridiculous here. 22 cents a kw that I currently pay.

 

[Wvapoker]

My Model 3 runs on coal here in WV so I pay 11 cents per Kw. Even with our mild winter so far I have yet to see the snowflake but have 5 to 8 dots on the regen side of the meter. I work from home so I don’t leave the house at the same time everyday so using the “depart at” setting doesn’t work for me.

I start the day with a 90% charge which usually drops to 89%. I’ve been toying with heating the cabin and restart charging at 25 minutes.

I really doesn’t seem to help.

Just get in drive.

 

[Akikiki]

Yea electricity rates are ridiculous here. 22 cents a kw that I currently pay.

Excuse me. That's not ridiculous. We would love that rate here. It's 31-32 a kw and on the Hawaii Big Island its 36. Want to trade rates? There !! Feel better about yours?

 

[toolman335]

Up in NH we're around 9 cents per kw. I do NOT complain about that.
I was just in Hawaii and saw your gas prices. 31-36 is a good deal lol.

 

[Yang_H]

Excuse me. That's not ridiculous. We would love that rate here. It's 31-32 a kw and on the Hawaii Big Island its 36. Want to trade rates? There !! Feel better about yours?

Isn't Hawaii perfect for solar panels? I would love to have solar panels but I'm living at cloudy Pittsburgh and based on all the information I could collect installing solar panels is just a bad investment.

 

[Akikiki]

Yes, Hawaii is perfect for solar. Many of us that drive EVs and particularly Tesla's have solar. I've had solar since 2009. I've generated more than 60 million wh. I make more power than I use to charge the Tesla. I've not paid to charge my Tesla since I owned my first one. No gas or no electricity to drive.

My long range plan was 1) Solar to charge an EV. 2) EV, 3) energy storage. For charging, for reduced house power costs and backup.

Our breakeven point is usually about 6-6.5 years with tax credits. Even if it was double that showing the reduced electric bill to any prospective buyer is well worth the money.

I can't speak to your situation and whether one should install solar. Federal tax credit is 26% this year. And Hawaii tax credit is 35%. You can see why we like solar.

 

[ZOMGVTEK]

Preheating will warm the battery in later software versions. The dual motor cars have effectively twice the heating power, but it still takes 20-30 minutes to get vaguely warm, and maybe an hour or more to fully warm up depending how cold it is. If you have a single motor car it’s going to be a slow go, preheat 30 minutes before leaving and hope for the best. It will warm a little bit faster while also charging, but that’s not that significant. I suspect the major issue from preheating through the motor is how uneven it is initially. The cells at the end of the string take a fair bit to start warming, so the regen power is most likely limited by the minimum cell temperature or some vague average of the internal resistance. Charging does warm the cells fairly evenly, so this is likely to have a more rapid initial impact. As far as the ‘best’ way goes, I’d vote preheat while plugged in for 30 minutes before departure. As you drive the cell temps should equalize and some more regen dots should go away. You could bump the max charge and speed the process up a bit, that’s not likely an issue at all. It’s probably not really going to help all that much, since as the SOC rises, the regen will become inherently more limited. What you really want is moderate cell temperature, and that just takes time.

 

[toolman335]

30 minutes to pre-heat uses a lot of energy. The cabin is toasty warm in about 3 minutes. To me that's the most energy efficient way to go for my 10 minute commute.

 

[Twochewy]

I agree. I usually charge my car when it's warm after driving it. Never pre-heat as the cabin & seat heaters work well. Don't care about the loss of regen in winter vs. wasting energy to heat the battery.

 

[mswlogo]

Up in NH we're around 9 cents per kw. I do NOT complain about that.
I was just in Hawaii and saw your gas prices. 31-36 is a good deal lol.

Hmmm, my NH rates are as high as they are in MA around $0.26 / kWh.

SuperCharger Rate is based on time (soon to change) but on average you end up about the same kWh rate as MA ($0.27 / kWh).

Some towns in MA and NH have their own Utility companies. So your comment of "NH" is not appropriate, your town could differ.

I know a lot of folks only quote energy and leave out Distribution, Transmission, etc.

https://www.eversource.com/content/docs/default-source/rates-tariffs/nh-electric-rates.pdf

Rate R, Residential Standard Service Available to customers living in individual residences and apartments.
• Customer Charge (per month): $13.81
• Distribution Charge (per kWh): 4.508 cents
• Transmission Charge (per kWh): 2.241 cents
• Stranded Cost Recovery Charge (per kWh): 1.764 cents
• System Benefits Charge (per kWh): 0.586 cents
• Energy Charge (per kWh): 8.825 cents

~$0.18 /kWh plus $13.81 base charge (I believe we pay more than this, I'd have to double check the bill).

There is also Rate G that is tiered. And there is Metered hot water etc.

NH is #7 on most expensive Electricty States in the country.

Which State Has the Highest Electricity Rate?

You might want to recheck you're bill

 

[mswlogo]

30 minutes to pre-heat uses a lot of energy. The cabin is toasty warm in about 3 minutes. To me that's the most energy efficient way to go for my 10 minute commute.

So nice to see folks coming to their senses on this topic. I agree that the Model 3 heats the cabin so fast I'm was more comfortable leaving in a "cold" Model 3 than I was in a warmed up ICE. Model 3 warmed so fast I never missed the heated steering wheel I had prior.

My Model X does not heat the cabin quite as quickly as the Model 3 unfortunately. But the heated Steering does make up for it. So it's about even comfort wise over the same time span.

BTW Model S/X (Raven) preheats the battery WHILE DRIVING unless you enable range mode.