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I’ve had my egolf a couple of months now and on the whole I do love driving it.

Tho like many, the one main weakness of the car is the range, but have been coping with it overall.
however today I had such A shock. Being a particularly cold day in london I put the heating on to 28 and but the setting at 3/4 intensity, not thinking anything of it. Then I looked at my gauge, it had dropped to 50% and I’d only been driving 19 minutes (and it was fully Charged at the start of the trip) I was absolutely shocked it had gone so low so quickly. I had lots of driving to do too, I had to stop at a charge point and top up. This had never happened before!

Totally a lesson to myself. I usually preheat but forgot today. You really can’t leave the hating on anything but auto unless you want a serious battery drain!,
 

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I don't own a Golf, but this doesn't sound right. Especially saying you're in London, it means you likely weren't moving particularly far or fast in those 19 minutes either.

Even in a car with no heat pump system you shouldn't really be looking at more than about 40% loss in range with the heaters on full power. I've been in cars with around half the battery size of your car (Peugeot iOn 16kWh) and the situation you describe sounds like that would be a fairly bad day even in that car.

As you said yourself, preheat. Keep the climate controls set to keep the car comfortable, not hot.

But definitely keep an eye on how your battery is behaving. Maybe another Golf owner will come along and say that's normal for your model. But from an outsider's point of view it seems very poor unless that 19 minutes driving was done on a motorway at 70+mph.
 

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It’s estimated range. Look at the bars and they won’t have dropped massively. Turning heating off will put range estimate back up. Try seat heaters only. Try coast when you can.
 

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I wondered about ancillary equipment and the power needed when considering my e Golf.

As I recall the heater uses about 600w which makes sense. Imagine putting a 2kWh fan heater in your car . That would be toasty!

So, 600w seems about right which by my calculation would draw about 2 miles of range per hour of driving.
 

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As with nearly all electric cars, the maximum drain from the HV battery is when you command a very high heat in the cabin, when the outside temperature is very cold.
The initial drain on the range will be huge, but as the car cabin rises the demand on the HV battery will decrease.
When I owed a VW GTE - I found requesting a high heat setting in cold weather, would absolutely murder the range instantly.
The higher heat setting, the biggest instant reduction in range on the GOM.
If I remember correctly, the max setting on the heater is about 30.
So asking for 28 is almost flat out !.
When the cabin has reached temperature, you will find the loss of range to be only about 2 - 3 miles, very small.
Pre heating is your HV batteries best friend in these situations.
Heated seats ( if you have them ) will only reduce the range by about 2 miles, instant heat as well !.
Next time, if you have forgotten to pre heat, try this.
When you enter the car and power it up.
While looking at the GOM, turn on your heated seats.
You should only see about a 2 - 3 mile reduction.
Now, turn on the climate control and set you required fan speed, again the GOM will hardly be affected.
Now start increasing the heat control, while watch the GOM.
As you increase the demand for heat, you can see the affect on the range !.
When start to reach figures about 23 you see the range decrease rapidly !.
As you reach 27 and above, the drop in range is massive.
Try and find a “Sweet” spot balance between heat required and high loss in range.
At least by going this, you can see what demand you are placing on the range by your request for heat in the cabin.
Oh ...... The A/C in the summer has a similar effect, but a little less demanding on the range than using the heater.
Again, pre cooling is the way to go !.
Good luck with the experiment!.
 

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28? That's what my GF sets it to. :)

I have to keep my Fluence at 18 to have any chance of reaching London.
 

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I wondered about ancillary equipment and the power needed when considering my e Golf.

As I recall the heater uses about 600w which makes sense. Imagine putting a 2kWh fan heater in your car . That would be toasty!

So, 600w seems about right which by my calculation would draw about 2 miles of range per hour of driving.
it’s 6-7kw! 600W would barely warm your feet! So it can make a sizeable dent in range.
 

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it’s 6-7kw! 600W would barely warm your feet! So it can make a sizeable dent in range.
Crikey, where did that figure come from? My entire workshop, all machines & heating running wouldn't draw that.

A 7kW heater would heat about 100 cubic metres.

600w will do about 8 cubic metres.
 

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it’s 6-7kw! 600W would barely warm your feet! So it can make a sizeable dent in range.
It can’t be that much?

If it were, pre-heating would suck up my entire 32A charging current, and I used to pre-heat it just fine on the granny charger at circa 2kw?

I think it’s much nearer to 1kw than 6 or 7...
 

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Last night out of interest I left my TM3 un-plugged to see what affect pre-heating would have. I know it was 75% the previously evening and by 07:00am with ~25 mins pre-heating the battery was at 70%. Battery pack had dropped to 9C so that wasn't helping.

I know my EV isn't as efficient at heating as others plus it usually starts at 6-8kw draw just for pre-heating when plugged in. That is an initial draw which quickly settles down to more like 2-3kw.
 

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Last night out of interest I left my TM3 un-plugged to see what affect pre-heating would have. I know it was 75% the previously evening and by 07:00am with ~25 mins pre-heating the battery was at 70%.
You used about 2.5kWh in about 25 mins then? Sounds about right.

I’ve often pre-heated my e-Golf when away overnight and not plugged in, it seems to drop the range from the previous evening by 6-10 miles max. I don’t have a battery percentage figure unfortunately.
 

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28 degrees, are you using your car as a vivarium?

It's like my other half who has no concept of how climate control works, and thinks if you get in the car and whack it up to full heat that it will warm up quicker. I'm always explaining that if you set a comfortable temperature of 20 degrees that the car will still output maximum possible heat until it reaches that set temperature, and then you don't need to keep turning the temperature down again once your face starts melting.
 

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Crikey, where did that figure come from? My entire workshop, all machines & heating running wouldn't draw that.

A 7kW heater would heat about 100 cubic metres.

600w will do about 8 cubic metres.
As mentioned already, an air space heater of 600 watts will barely warm your toes in a car...

Around 5-6kW is typical for a resistance heater in an EV on full power during the initial warm up period, however it will level off at a lower figure once the cabin is up to temperature, say around 3kW, depending on outside temperature. In a car with a heat pump divide those figures by 2 or 3.

As for your workshop not needing that much heating, your workshop is no doubt much better insulated than the cabin of a car - which is largely single glazed glass and thin steel (including the bottom) which loses heat link a sieve. Your workshop is also not suffering from evaporative cooling of rain drops while travelling at motorway speeds. (EG equivalent to a 70mph storm wind blowing over your house while it's raining)

Also keep in mind that a heater in a house is constantly re-heating the same air in a convective cycle, while the heater in a car is taking fresh freezing cold air from the outside and heating it up to the required temperature in a single "cycle". (Unless you put the car in recirc mode for a while) This uses a lot more energy that continuing to heat the same parcel of air, but is necessary to keep the air in a small space fresh and avoid excessive moisture buildup.

Car cabins are exceptionally poorly insulated compared to a room in a house or even a garage, the only reason we get away with it in an ICE vehicle is because there is tons of waste heat literally being thrown away all the time which can be diverted to heat that extremely leaky cabin - so no incentive for manfacturers of ICE vehicles to make any attempt to insulate the cabin.

That may need to change with EV's though, where you pay for cabin heating directly in lost range.

As for the original poster setting their heater to 28 degrees - I just about fell over in laughter when I read that... it's a car, not a sauna. Put a jacket on! :LOL:
 

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It can’t be that much?

If it were, pre-heating would suck up my entire 32A charging current, and I used to pre-heat it just fine on the granny charger at circa 2kw?

I think it’s much nearer to 1kw than 6 or 7...
The resistance heater in my Ion draws 5.5kW on full during initial heat up. Once the temperature has stabalised it drops to around 2-3kW depending on conditions.

A heat pump can reduce this by a factor of 2 to 3 depending on conditions. Initial heatup on a heat pump is still going to be at least 2kW and cars with a heat pump may suppliment the heat pump with a resistance heater for a while as well especially at very low ambient temperatures.

Heating a car takes a lot of energy because it's so leaky and poorly insulated...
 

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So takeaways from this thread:
  • keep the target temperature down and use a target temperature rather than manual
  • use pre-heat if plugged in
  • if you use a lot of heat then get a car with a heat pump
  • don't worry about the GOM reducing, watch the battery percentage
 

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The resistance heater in my Ion draws 5.5kW on full during initial heat up. Once the temperature has stabalised it drops to around 2-3kW depending on conditions.
Out of interest, how are you measuring that? How much of that plugged in pre-heat is down to charging the battery as well as providing power to the resistive cabin heater?

Is the Ion resistive heater typical?

I ask because my e-Golf starts it’s pre-heat cycle about 30 mins before departure whether it’s plugged into my 7kw wall charger, the 2.1kw granny charger or even not plugged in at all.

When pre-heated and not plugged in the range doesn’t drop anywhere near as much as up to 6kw being pulled from the battery.

Maybe the Ion has a more powerful resistive heater, maybe the e-Golfs is less powerful, either way I’m still struggling with it drawing as much as you say.
 

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The LEAF24 Gen 2 definitely has a 5 kW PTC as part of its heat pump, the early Gen 1 only 4 kW. On a "3.6" kW charger (actually adds less than that to the battery) the pre-heating initially reduces the battery level before it turns down and the charge increases.
Don't know about the triplets or e-Golf.
 

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Out of interest, how are you measuring that? How much of that plugged in pre-heat is down to charging the battery as well as providing power to the resistive cabin heater?
There is no plugged in preheat in an Ion - you can't run the heater when plugged in, only when the car is unplugged and fully into the ready to drive mode. (There is also no heater/acc only mode, just acc mode with blower fan but no heater)

I'm measuring it using diagnostic software that can query the heating control ECU directly for the amount of power drawn by the heater alone. (Canion, Hobdrive or Diagbox can all give these figures on an Ion)
Is the Ion resistive heater typical?
In terms of power use, yeah probably. Most EV's with resistive heaters seem to be around the 5-6kW range. Remember though this is when they're initially going flat out to get the cabin temperature up quickly, power use drops off after the initial heat up to maintain a steady temperature. How much depends on outside conditions and what you set the temperature to. I find mine typically settles down to about 3kW in near freezing conditions.

The Ion's heater is a water PTC heater - meaning that it heats a fluid which is similar to engine coolant up to a maximum of about 60C and this is pumped through a regular heater matrix. This is slow to warm up and not very efficient due to all the thermal mass, piping etc. Many EV's with resistive heaters have what is essentially a fan heater - coils of hot wire directly in the stream of air flow. This is much faster to heat up just like a 3 pin fan heater and a little bit more efficient due to low thermal mass - only the heater element needs to heat up.

A heat pump is best of all of course, although heat pumps still need a resistive heater to speed up the initial heat up (since a heat pump can take a minute or so to get up to temperature) and also in extremely cold ambient temperatures where a heat pump alone can't produce enough heat, in those conditions a resistive heater gives the heat pump a helping hand, but even then the combined power use is less than a resistive heater alone for the same heat output.
 

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Just checked my heat pump equipped e-Golf: the PTC heater is 5.0 kW, 350 V (made in Germany, of course). That means it is pulling 14.3 amps maximum. I assume the PTC heater in models without the heat pump is the same. The PTC heats fluid (as does the heat pump) which moves through the cabin air/liquid heat exchanger where cabin air is blown across the exchanger to warm the cabin air using heat from the hot fluid.
 
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