Heating uses loads of power

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revpeterw

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Probably you all know this but I noticed that using the heating set to 22 deg uses 10A from the battery, on a cold day (6 deg).
That equates to 4kW of power being drawn from the battery, which totally accounts for my consumption in winter dropping to 3miles/kWh from 4miles/kWh.
In summer, at 60mph the energy load is approx 15kW, whereas in winter this ups to 19kW with the heating on! Ouch.
By the way, the heated seats uses a lot less power maybe 1A (400W) per seat. Set the heating to 17 degrees and use the heated seat gives a lot more range!
 
revpeterw said:
Probably you all know this but I noticed that using the heating set to 22 deg uses 10A from the battery, on a cold day (6 deg).
That equates to 4kW of power being drawn from the battery, which totally accounts for my consumption in winter dropping to 3miles/kWh from 4miles/kWh.
In summer, at 60mph the energy load is approx 15kW, whereas in winter this ups to 19kW with the heating on! Ouch.
By the way, the heated seats uses a lot less power maybe 1A (400W) per seat. Set the heating to 17 degrees and use the heated seat gives a lot more range!
Click to expand...
unless you have the windows open the heating is unlikely to be using 4kw for very long. 4kw would heat a fairly large room and the inside of an MG5 isn't that much volume.
 
The power demand cycles up and down.... time off... time on..... the heater uses 12 amps on my 5. The higher the heat demand - and lower the cabin temperature is.... the longer the demand is for....
 
It’s noticeable on short drives though, I averaged 2miles/ kWh on one this morning due to heating + it being mostly uphill.
 
revpeterw said:
Probably you all know this but I noticed that using the heating set to 22 deg uses 10A from the battery, on a cold day (6 deg).
That equates to 4kW of power being drawn from the battery, which totally accounts for my consumption in winter dropping to 3miles/kWh from 4miles/kWh.
In summer, at 60mph the energy load is approx 15kW, whereas in winter this ups to 19kW with the heating on! Ouch.
By the way, the heated seats uses a lot less power maybe 1A (400W) per seat. Set the heating to 17 degrees and use the heated seat gives a lot more range!
Click to expand...

Hi RevPeterW

how to you find out the additional current used by the heater ie 10A as above, and the seat heater at 1A? I've an MG4, so you might have a display that we don't? I agree the heater when warm / hot does eat the power initially as the cabin heats, plus I like it fairly warm.

Using V = W/A = 4000/10 I guess the main battery is 400 V? Is it exactly 400 V?

Many thanks!
 
MartinSEsr said:
how to you find out the additional current used by the heater ie 10A as above, and the seat heater at 1A? I've an MG4, so you might have a display that we don't?
Click to expand...
The MG5 FL can display actual HV battery voltage, current and motor rpm in one of the menus.
 
revpeterw said:
Probably you all know this but I noticed that using the heating set to 22 deg uses 10A from the battery, on a cold day (6 deg).
That equates to 4kW of power being drawn from the battery, which totally accounts for my consumption in winter dropping to 3miles/kWh from 4miles/kWh.
In summer, at 60mph the energy load is approx 15kW, whereas in winter this ups to 19kW with the heating on! Ouch.
By the way, the heated seats uses a lot less power maybe 1A (400W) per seat. Set the heating to 17 degrees and use the heated seat gives a lot more range!
Click to expand...
Thanks to a lorry fire closing the A2 this morning I had 2 1/2 hours to study the current being used by the heater and heated seat on my MG5. It was 3degrees outside and I had the heating set to 21. It did very occasionally hit 10A but most of the time it was going between 1 and 2 or 5 and 6. The heated seat took between 1A and 2A but it doesnt need to be on for very long before you get quite warm in the backside. In the 2 1/2 hours I was sat in the snow with the car on and the heater and entertainment system running I think I used about 12% of the battery. I was pretty happy with that considering the circumstances.
 
Coulomb said:
I'll bet it was an ICE lorry. Those ICE vehicles are always catching fire... Thanks for using your time profitably.
Click to expand...
How could that possibly be ? Diesel can't catch fire !!! :unsure:
 
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I can’t remember where I found this (credit to whoever did it.)
 
Heating an MG5 has a far bigger effect on efficiency than cooling, but then most modern EVs use a heat pump instead of a PTC heater.
 
Driving my MG4 Trophy this week with AC on or off - difference in estimated range was only 4-5 miles = approx. 2kWh although the estimated range increased when I turned AC off but left heating on. Not too much to worry about unless energy is running low.
 
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I have noticed recently that the difference in heat output doesn't change much from 22°C to max it's certainly not roasting. So from what I can gather if you reduce the temperature to say 17°C then you get more [ estimated ] range? I don't see that at all. As soon as the fan is switched on my range is cut by about 9 miles.

Coulomb said:
I'll bet it was an ICE lorry. Those ICE vehicles are always catching fire... Thanks for using your time profitably.
Click to expand...
I noticed BBC news briefly mentioned an electric bus was on fire in London is there such a thing in this country? no mention of the lorry fire...
 
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snowyy said:
I have noticed recently that the difference in heat output doesn't change much from 22c to max it's certainly not roasting. So from what i can gather if you reduce the temperature to say17c then you get more range? i don't see that at all.As soon as the fan is switched on my range is cut by about 9 miles.
Click to expand...
That's using the guessometer I assume. Mine does the same but the miles/kWh does not alter. Estimated range goes up when fan is off.
 
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aread2 said:
There are over 1000 electric buses in London. The entire fleet of 9000+ will be emission free by 2030.
Click to expand...
Oh good not noticed one when i have been there. Who makes them do you know?
 
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