kW

[Giveittomebaby]

Ok, i've been wondering this for a while and not found the answer...

Assuming all things being equal, driving on a flat road, minimal wind, constant speed etc etc what is the impact on a kW from using air con cold, heaters, heated seats, lights etc

ie if 1kW is 100%

Does anyone know what the battery use/power drain is to use the ancillaries? Is it maybe 3% for heating, 1% for seats and so on?

I suppose what i'm getting at is when i turn the aircon on for example, in percentage terms, what's the additional drain on the battery?

 

[Adopado]

Ok, i've been wondering this for a while and not found the answer...

Assuming all things being equal, driving on a flat road, minimal wind, constant speed etc etc what is the impact on a kW from using air con cold, heaters, heated seats, lights etc

ie if 1kW is 100%

Does anyone know what the battery use/power drain is to use the ancillaries? Is it maybe 3% for heating, 1% for seats and so on?

I suppose what i'm getting at is when i turn the aircon on for example, in percentage terms, what's the additional drain on the battery?

There are so many variables it's bind bending. We are talking about a Tesla here not an 8 year old Nissan Leaf. Using heating/cooling is not going to impact your use of the car... and you haven't even chosen a model to base the calculation on.

"Assuming all things being equal, driving on a flat road, minimal wind, constant speed etc etc" ... well that's a set of circumstances that doesn't exist in the real world either!

If you want a handle on these things (and in some extreme conditions) check out Bjorn Nyland's videos on Youtube.

 

[guicane]

I don't have the actual figures for you but before tesla I had a Mitsubishi Outlander PHEV which did on average 20 miles on a full charge. So I wanted to get the most of this range by not using climate control if possible. What I found is that on a hot day with aircon on full blast the range would be very little impacted but if i needed to have the heating on full blast I wouldn't even bother going electric only and would let the engine kick in as the range would be almost wiped out in a few miles.

 

[Andy_T_73]

The heater, especially on pre heat pump cars, can suck up to 6KW (as I recall from a Bjorn video) but not all the time as it modulates according to cabin temp. Not sure AC draw in KW but a lot less than the 6KW heater, one of the reasons summer consumption with AC on is much lower than winter running the heater. If you really want to find out get Scan My Tesla and an OBD dongle As mentioned Bjorn has loads on it on YouTube, that's how he got the data.

 

[Plagued]

We are talking about a Tesla here not an 8 year old Nissan Leaf. Using heating/cooling is not going to impact your use of the car... and you haven't even chosen a model to base the calculation on.

you say that, but generating 1Kw of resistive heat uses 1Kw in a tesla and 1Kw in an 8 year old leaf. Admittedly the Tesla can move heating and cooling about better, but on most shorter journeys that's not going to make much difference. Heat pumps can get you a 3+ x return on energy vs heat/cooling but they are also hugely variable.
As Andy said above my Model 3 can pull up to 6KW but my Leaf Only pulls about 4KW and then drops to about 2KW in most heating/cooling once the temperature stabilises. My assumption would be you'd save about 2-3KW if you didn't use heating or aircon so in an hour you could say 3KWH or about 12 miles of range ...

 

[Undecided_2]

I played around on a 460 mile drive heading to Scotland. The SUC I was stopping at would have left me 3% SOC - 70mph, 11c and climate on, miles of long inclines up hills. SUC was 185 miles away. I switched off climate. Eventually, I slowed to 68mph as it stayed at 3% on arrival for an hour. When I arrived I had 8% SOC.

Summary: For my journey climate made little difference. Adjusting speed -2mph made a 5% difference for the last couple of hours.

The biggest impact that I’ve seen is temperature. Heading south 485miles. Left at -1c. Travelled 185 miles and had 11% SOC when arriving at SUC.

Left SUC 8c 70% SOC and travelled 250 miles and arrived SUC with 19%. The temperature kept climbing to around 13c and the % drop slowed significantly.

 

[GRiLLA]

This might help, taken from my resistive heated LR Model 3

Climate i set to 20% and generally I pre-condition before the recorded miles start. Either side of my chosen temperature the impact is about the same cooling as warming.

 

[GRiLLA]

The biggest impact that I’ve seen is temperature.

I would say rain/snow is the biggest impact by a long way. I've easily seen the wh/mile double in heavy rain.

 

[Jason71]

looking at the terms in which you asked the question. look at it this way.
If you on a motorway in winter averaging 60mph and using 300wh/m then that means you are using 18kw per hour or 18kwh.
If the M3 is pulling 2KW from its heater in a steady state then that would be 2kwh which means the heater is responsible for2/18 or 11% of the energy being used.
AC is typically less than heating I am guessing 1kw and heated seats probably 50w each

 

[init6]

Ok, i've been wondering this for a while and not found the answer...

There is no answer.

 

[Llama.]

If you are driving an EV with 300+ miles of range and a hearpump. Just drive the car and use the heating aircon as you like. It will make no noticeable difference to any journey.

Just enjoy.

 

[init6]

looking at the terms in which you asked the question. look at it this way.
If you on a motorway in winter averaging 60mph and using 300wh/m then that means you are using 18kw per hour or 18kwh.
If the M3 is pulling 2KW from its heater in a steady state then that would be 2kwh which means the heater is responsible for2/18 or 11% of the energy being used.
AC is typically less than heating I am guessing 1kw and heated seats probably 50w each

But they won't be on all the time and the duty cycle will be dependent on the outside air temp. Oh and also how much insulation you're carrying in your butt

 

[Jason71]

But they won't be on all the time and the duty cycle will be dependent on the outside air temp. Oh and also how much insulation you're carrying in your butt

agreed and yet probably still more helpful to the op than "there is no answer"

 

[init6]

agreed and yet probably still more helpful to the op than "there is no answer"

Only if it's a right answer and you can't give a right answer with the data supplied by the OP. Hence no answer

 

[Undecided_2]

I would say rain/snow is the biggest impact by a long way. I've easily seen the wh/mile double in heavy rain.

I haven’t really checked on a rainy day but that seems right to me as it requires more torque due to resistance and wet roads causing resistance coupled with lights on, climate and wipers. We wouldn’t notice it much on an ICE other than MPG dropping. I suppose it’s significant on our EVs as a 5% drop in efficiency is noticeable if you have 200 mile range whereas on an ICE that does 40 mpg is less noticeable. (I’m no expert though)

 

[Giveittomebaby]

There is no answer.

Not on this thread at least!!

Of course there’s an answer.

Scientifically, in equal conditions, on say a model 3 2021 version, the impact of non drive related power being consumed on like for like cars in like for like conditions, must be measurable.

I’d bet Tesla know the answer, and I’d bet they use this answer when appraising different methods for heating or cooling the cabin - I’d just be interested in knowing too!

 

[init6]

Not on this thread at least!!

Of course there’s an answer.

Scientifically, in equal conditions, on say a model 3 2021 version, the impact of non drive related power being consumed on like for like cars in like for like conditions, must be measurable.

You haven't specified what the equal conditions are. E.g. a car driving in +20C air will use less heating than a car driving in -20C air. Your cabin temperature setting will also determine the duty cycle of the heating or A/C. The wh/m will vary depending on the journey, so having the heating as a percentage of a variable figure is even less useful.
We could all guess an answer, but my guess based on a Scottish Winter would be completely different from someone in say Kent. And vice versa for Summer. So ultimately you'd have a wide range of guesses based on variables that may not equate to your normal usage.

How useful is that?

If you really want a figure, 7.468% is what I've calculated. Note I've gone to 3 decimal places so much more accurate than the other guesses.

 

[Giveittomebaby]

You haven't specified what the equal conditions are. E.g. a car driving in +20C air will use less heating than a car driving in -20C air. Your cabin temperature setting will also determine the duty cycle of the heating or A/C. The wh/m will vary depending on the journey, so having the heating as a percentage of a variable figure is even less useful.
We could all guess an answer, but my guess based on a Scottish Winter would be completely different from someone in say Kent. And vice versa for Summer. So ultimately you'd have a wide range of guesses based on variables that may not equate to your normal usage.

How useful is that?

If you really want a figure, 7.468% is what I've calculated. Note I've gone to 3 decimal places so much more accurate than the other guesses.

Yeah. Pretty useless

 

[Casss]

I would say rain/snow is the biggest impact by a long way. I've easily seen the wh/mile double in heavy rain.

Agree 100%.

It's funny how stupidly stupidly complicated it is to calculate the exact impact of driving in rain too.

Surface energy, water dispersal, tyre tread pattern, tyre wear, sling off the tyre (compound, depth of water, tarmac temperature, surface energy of the road), traffic, tarmac compound, air moisture level, wind speed and direction. Oh and then basically all of those variables change dependent on speed and torque being applied, (and per wheel in some cases because they all affect each other differently when you factor in that any turbulent air impacts where the spray goes).

Almost impossible to create any meaningful, real world equivalent test for it that wouldn't cost a fortune and be useful to anyone, so I'd go for "a lot" and "around twice as inefficient" as a good ball park lol.

It's one of those.

 

[Jason71]

I haven’t really checked on a rainy day but that seems right to me as it requires more torque due to resistance and wet roads causing resistance coupled with lights on, climate and wipers. We wouldn’t notice it much on an ICE other than MPG dropping. I suppose it’s significant on our EVs as a 5% drop in efficiency is noticeable if you have 200 mile range whereas on an ICE that does 40 mpg is less noticeable. (I’m no expert though)

its less noticible in ICE since they are only 20-30% efficient in the first place versus 90% in an EV so if the resistance goes up or the speed and the energy requirement increase by say 20% its only 20% of 30% not 20% of 90% that it is in an EV so barely noticible. I am simplifying but the principal is correct