"Dramatic" reduction in cold weather range. Why?

[cattlerepairman]

2017 eGolf, 70k Km

I have driven my eGolf for 3 winters, this is winter #4. SAME everything, even same winter tires (getting worn, but still...).
eGolf lives outside, under a car port, so the battery gets good and cold.
The ONLY difference from the last winters is that I tend to drive off without having used the eManager to preheat the car (due to more unpredictable schedule).

I was used to a range of roughly 170 km in cold weather. "Cold" being around -10/-15 degrees Celsius. Around 180/185 km range at around freezing.

NOW I am lucky to squeeze out 160 km in moderate weather (around 0 - plus 3 degrees), at times even less, maybe 150 km (like yesterday, and it was relatively "warm" at plus 5. I had the cabin heat turned down to 20 degrees C which I normally do).

What I notice is that CONSUMPTION seems way up. In the warm time of the year I see 13-14 kWh/100 km (on normal mode, not driving particularly range-consciously). When cold I used to see 17-18 kWh.

NOW I am seeing 19-22 kWh/100km, with around 20 kWh being common.

So, I do not think that it is a scenario where the battery lost capacity that badly,

WHAT'S HAPPENING??

I checked the service brakes for sticking/binding - cleaned and lubed and all good. Nothing dragging.

Now that I am writing this, I am thinking, with the cabin pre-heat, the battery supplies a good current to the heater and receives a good current from the charger at the same time. That would cut down on the heater draw when leaving and it would also have brought the battery temperature up a little bit, from having the current flow for at least 15 mins or so before driving off. Hmmmm. Maybe that is all it is? Such a huge effect from a small activity? What do you think?

 

[f1geek]

I do not think charging the battery pack will warm it much since the C rate is so low, but pre-heating the cabin will make a big difference, as that is ~5 kW draw, I believe if the PTC heater is running (I can't remember if it says 5 kW or 4 kW - it has a sticker on it that you can check).

 

[miamor]

NOW I am lucky to squeeze out 160 km in moderate weather (around 0 - plus 3 degrees), at times even less, maybe 150 km

I have just recently tried to experiment to see what the heater draws. So i made the Emgr heat cabin from 70F to 80F while plugged into a L2 charge point after the car had charged fully. The charge point indicated 1.3kW demand. So if the resistance heater is rated to much more, I was not seeing that. Perhaps it can draw 4-5kW if there is much more heat needed, say from 40F to 80F.
But you are addressing what I was thinking; how much can that heater draw?

I had another case where after car was fully charged, charge point showed an add'l 2kWh used since it Emailed me the car was fully charged overnight and I left it connected to power the heater later that day for the 9am departure time. I was wondering how a half hour of preheat could use up 2kWh. That now makes more sense if the heater draws a maximum 4kW for 1/2hr.

So, cattlerepairman, that could translate to 12km lost by using the battery to heat cabin. I made a rough calculation of 4mi/ kWh, for 2 kWh of heat use, 8mi = about 12km lost to heating!

 

[tomblandford]

Pre-heating the cabin really seems to help the range in winter. My schedule is also unpredictable, so I have a habit of turning on the A/C when I get out the shower!

The VW app is very slow to open, but I found the VW ID app can turn on A/C in the eGolf and opens faster!! I have both apps installed. No issues.

 

[cctop]

In my 2019 SE (no heat pump) I lose about 10% of range on the Guess-O-Meter when the cabin heater is on.

 

[Fugazi]

My range drops to about half from summer to winter. ~300 to 150 km.
- Cabin heating, seat heating
- Battery is cold
- Rolling and aero losses are bigger

 

[f1geek]

My range drops to about half from summer to winter. ~300 to 150 km.
- Cabin heating, seat heating
- Battery is cold
- Rolling and aero losses are bigger

What is the ambient temperature when you drive the car? Have you tried preheating the car before a trip?

 

[hcmken]

I also drive in below freezing temps in the winter. We keep our eGolf in a garage that is 20F warmer than the outside temp. Our range loss in the winter seems to be around 15-18% over the past 2.5 years of ownership.

I’m curious about preheating … what is meant by preheating using emanager? Is there an app that’s available for smartphones, or is there the need to go into the car and turn the heat or defrost on?

I’ve found the software in the car to offer very limited programming options, but perhaps there’s an app I’ve been unaware of.

 

[Fugazi]

In summer I don't need heating or cooling. So, no power going there.
Winter usually -5 C (-15 .. +5). No pre-heating and car is standing out in the cold. I don't really mind the consumption. Driving is still almost for free, and I can do with the short range.

 

[Fluxcapacitor]

PTC heater is rated at 7kW. So it can pull up to that much depending on demand. So if you’re not preheating whilst plugged in, all that power to warm the cabin comes from the battery, which will have a dramatic effect on the consumption number and consequent range in very cold weather.

 

[f1geek]

I also drive in below freezing temps in the winter. We keep our eGolf in a garage that is 20F warmer than the outside temp. Our range loss in the winter seems to be around 15-18% over the past 2.5 years of ownership.

I’m curious about preheating … what is meant by preheating using emanager? Is there an app that’s available for smartphones, or is there the need to go into the car and turn the heat or defrost on?

I’ve found the software in the car to offer very limited programming options, but perhaps there’s an app I’ve been unaware of.

Using e-manager you can set a charge timer so car is charged and cabin is heated to desired temperature at the departure time. This enables you to warm cabin using house power instead of battery power, giving you more winter driving range.

 

[Fugazi]

I tried the e-manager. If I would leave every day the same time, I'm sure I'd use it. But my driving is random times and it should be remote access to work for me. Charging I do according to electricity price so this is not a constant time either.

 

[Fluxcapacitor]

I tried the e-manager. If I would leave every day the same time, I'm sure I'd use it. But my driving is random times and it should be remote access to work for me. Charging I do according to electricity price so this is not a constant time either.

Your options are to use the app (if it still works in your market, dead in US now) to remotely turn on heating 15 mins before departure whilst it’s plugged in and suck up the negligible cost of a couple of kWh at whatever price, or live with the reduced range.

 

[Fugazi]

I will try if the new software works. I have read reports in both directions.
If it works it will also be needed for the home automation to know the charge level of the battery.

 

[Curly]

Your options are to use the app (if it still works in your market, dead in US now) to remotely turn on heating 15 mins before departure whilst it’s plugged in and suck up the negligible cost of a couple of kWh at whatever price, or live with the reduced range.

I'm showing my ignorance, but perhaps there's a third option. What if you just go to the car 15 minutes before departure and turn it on "in person", instead of remotely, while it's plugged in? Does this warm up the cabin? It tells you on the display that it won't "start" while plugged in, but I know that the display activates pretty much completely, with the radio working, and the headlights and tail lights come on. I would think the seat heaters would turn on also if you wanted them heated before departure.

 

[Fugazi]

Not a bad idea at all IMHO. Especially when it's bloody cold like now (-20 C), that's a good quick and dirty solution.

 

[f1geek]

I'm showing my ignorance, but perhaps there's a third option. What if you just go to the car 15 minutes before departure and turn it on "in person", instead of remotely, while it's plugged in? Does this warm up the cabin? It tells you on the display that it won't "start" while plugged in, but I know that the display activates pretty much completely, with the radio working, and the headlights and tail lights come on. I would think the seat heaters would turn on also if you wanted them heated before departure.

Unless car shows “ready” message, no part of high voltage system (including heating) will work. You have to leave car on and key in car for the “walk up” method to work.