Best heating choices

[Bobbo8]

I will be taking a LONG trip in COLD temps and was wondering how should I heat the M3. How should I use the seat heaters and cabin heaters to not negatively impact the battery/mileage. Should I minimize them cabin heaters and depend on the seat heaters or the opposite?

 

[svp6]

If you really need range, preheat before you go, use seat heater instead of cabin heater, go slow.

That being said, why would you do that to yourself in a 50-70k car? I set the cabin heater at 72F, drive at same speed as average traffic in the area, and enjoy the ride. The energy app then tells me precisely how I am doing.

I usually set my supercharger as destination, and then monitor on energy if I will make it with 5% to spare (not the initial optimistic value, rather use the one that you observe after first 15 miles or so, it adjusts for your driving style / current conditions). If you are losing the battle, then you can modify the driving style.

I also multiply the actual distance by 1.3 in summer and 1.5 - 1.8 in winter to estimate how many rated miles I need. Never got stranded in 4 years.

 

[Knightshade]

Seat heaters use a lot less power than cabin heat, since that seems to be what you're asking.

But I agree with svp6, unless the trip is somewhere so remote you don't have supercharger access then use the cabin heater if the seat heater isn't good enough and just charge a few minutes longer at each stop.

 

[eprosenx]

FWIW, my M3 parks outside in Portland Oregon.

I have been *loving* preheating every single day. It is fantastic. And since I have a Wall Connector on a 60a circuit that provides up to 48a of 240v current to my car, I can fully heat the car and battery from shore power.

It is fantastic!

With the battery heating solution using the motor and the cabin heating, I draw nearly the full Wall Connector capacity for a brief period during initial heater startup.

I am pleased with my choice to wire the Wall Connector up for the full 60 amps!

 

[lolder]

Put the HVAC in manual by turning off the AC, set recirc to off, temp to about 65, select top ( defog/defrost ) vents, seat heaters on, and fan speed 3-5. If this keeps the windshield free of fog, fine. The heavy energy use occurs when you're in "Auto" when the car will frequently run the heat and AC. Keep the recirc off as moisture will build up from the occupants exhaling. Heating dryer outside air will be more efficient if you can avoid using the AC. If you are in cold high humidity conditions you'll have to de-humidify. When you select defog it turns the AC on. When you turn it off, the AC stays on and you have to manually turn it off again. Sometimes it's safer to put it in "Auto" instead of pushing all the touch screen toggles. You may have a lot of range reduction. Believe the trip energy graph and plan to arrive at charging stations with a good reserve. 20% in an EV is equal to about "E" in an ICE car that usually has a gallon or two when on "E". If you get stopped in traffic by road conditions, the heat takes 1-2 kw which is 3-10 miles/hr loss of range. If you run out of battery in an interstate tie-up you are really in trouble.

 

[Big Earl]

The air conditioning compressor won't run when it's below freezing, regardless of the HVAC setting.

I typically leave it in auto unless it starts roasting my feet (it usually starts doing this after about an hour of driving). At that point, I'll turn off the foot vents for a while.

 

[SSedan]

While supercharging I have set the cabin to 80f to bank some interior heat. I will do the same preheating at home if I will be pushing range.

I agree with the others far as worry about your comfort if not stretching range and set Superchargers as destinations so you can see what is going on and manage heat and speed accordingly.

 

[Bobbo8]

FWIW, my M3 parks outside in Portland Oregon.

I have been *loving* preheating every single day. It is fantastic. And since I have a Wall Connector on a 60a circuit that provides up to 48a of 240v current to my car, I can fully heat the car and battery from shore power.

It is fantastic!

With the battery heating solution using the motor and the cabin heating, I draw nearly the full Wall Connector capacity for a brief period during initial heater startup.

I am pleased with my choice to wire the Wall Connector up for the full 60 amps!

I have the same garage wall charging connector, it is fantastic for what you stated but also I dont have to go to the gas station in snow, rain, wind, etc. Love my M3!

 

[ewoodrick]

What's long? The only thing that really matters is spacing between Superchargers that you are going to use. If they are close, then just enjoy yourself. If they are far, then you will need to slow down and enjoy the scenery.