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Adaptive Heating?

Would "Adaptive Heating" Increase Efficiency


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Would adaptive controls improve the efficiency of the battery when using HVAC to heat the cabin? Many ICE vehicles, especially those with low power output, have the ability to disengage the AC while accelerating, returning power to the engine. If there was an option for "Adaptive Heating", that would disable the heater for things like accelerating, climbing a hill or anything that requires a power output of greater than a certain output of the wh/mi, do you think the efficiency would increase?

Would this be a better option than just driving with the heat off or really low?
 
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Ice cars turn off the compressor because it loads the engine, causing less power. Electric cars do not have that problem. The heat is resistive so turning it low or off is the only way to increase efficiency.
 
...ability to disengage the AC while accelerating, returning power to the engine...

I have not seen that HVAC/Heater would impair Tesla performance if there's enough battery for them (that means it's not displaying there are 10 miles left on your battery gauge).

Disabling HVAC/Heater would indeed save the energy but I don't see how it helps to boost performance.

...If there was an option for "Adaptive Heating", that would disable the heater for things like accelerating, climbing a hill or anything that requires a power output of greater than a certain output of the wh/mi, do you think the efficiency would increase?

Would this be a better option than just driving with the heat off or really low?

That creates havoc due to unpredictability because if you want the system to shut off the heater to save energy, you'll have to pray that there will be a hill coming up real soon, please!

Or the driver has to pray that the traffic would clear up real soon so the accelerator can be floored all the way so the system would automatically shut off the heater!
 
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huh? i think you guys are confused, or i worded my post wrong. since it's known the heater reduces the efficiency of the battery (uses more power to heat the cabin), it would make sense to be able to disable the heater given certain scenarios. this isn't a performance question, but efficiency in range and increased battery usage.

there have already been other threads and posts wanting the ability to simply control when the heat comes on (leave fan on, but disable heat). if the vehicle had a way to heat the cabin only when the vehicle was using either average or low energy output, it seems to reason it would be more efficient in this scenario.

i've been testing my energy output in 30-40° weather by driving with the heater off for 20-30 miles at a time and my wh/mi dropped by 100wh/mi each time. the car exhibits near summer numbers and range is increased. if the heater "kicked off" or at least reduced during the period the vehicle was "under stress" (acceleration, on a hill, etc), it could, theoretically, increase the range.

BTW - for me, adaptive heating would be another setting. this isn't something i would choose to have enabled all of the time. there should be an override to keep it "normal" or "auto". the auto button could change from AUTO-ADAPTIVE-OFF or the like.
 
Turning off your cabin heater during high power demand vs turning it off during low power demand will not have any measurable difference. The only times when your battery is being less efficiently used is when it's not operating at ideal temperatures. This is why you have power or regen limits when the battery is cold. Your car doesn't care if it's using the heater when you floor it or cruise.

Edit: In fact, it would be smart to turn the heat UP when you're driving more aggressively: Your car will capture some of the wasted heat from the battery/stator, and use it for heating the cabin when it can.
 
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In fact, it would be smart to turn the heat UP when you're driving more aggressively: Your car will capture some of the wasted heat from the battery/stator, and use it for heating the cabin when it can.
is this true? this may be the first time i've heard/read this. i've seen anecdotal postings that "flooring" it (especially in a dual motor) increases efficiency of the battery because it warms it faster, but there were varying opinions on the benefits.
 
is this true? this may be the first time i've heard/read this. i've seen anecdotal postings that "flooring" it (especially in a dual motor) increases efficiency of the battery because it warms it faster, but there were varying opinions on the benefits.
After checking, no. The S/X have their coolant loop running through HVAC but the 3 doesn't, must be for simplicity sake. My bad!

Edit: But yes, a warm battery will operate more efficiently than a cold one. Discharging at High and Low Temperatures
"As all drivers in cold countries know, a warm battery cranks the car engine better than a cold one. Cold temperature increases the internal resistance and lowers the capacity. A battery that provides 100 percent capacity at 27°C (80°F) will typically deliver only 50 percent at –18°C (0°F). The momentary capacity-decrease differs with battery chemistry."
 
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Sklith puts it well.

Watts are watts. And the battery doesn't care if the heater takes them during acceleration or otherwise. It's a performance issue for ICE cars, as every watt of power to the compressor isn't available to turn the wheels at that given moment, but not an efficiency one.

Your battery is like a bank account. This is like taking $100 cash out as part of a $10K vehicle purchase transaction, or "efficiency mode" and grabbing it from the ATM on the way home. Your bank account doesn't care; the total removed is the same.
 
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Would adaptive controls improve the efficiency of the battery when using HVAC to heat the cabin? Many ICE vehicles, especially those with low power output, have the ability to disengage the AC while accelerating, returning power to the engine. If there was an option for "Adaptive Heating", that would disable the heater for things like accelerating, climbing a hill or anything that requires a power output of greater than a certain output of the wh/mi, do you think the efficiency would increase?

Would this be a better option than just driving with the heat off or really low?

Does your commute long enough to require most of the battery?

If not, don't worry about it, just enjoy being warm. Forget about the battery.
 
...uses more power to heat the cabin), it would make sense to be able to disable the heater given certain scenarios. this isn't a performance question, but efficiency in range and increased battery usage...

True.

When your battery is about 20%, your cabin A/C and Heater are automatically reduced to preserve range.

So, adaptive heating is already in the algorithm.

However, to further the algorithm to climbing hill, flooring accelerator does not make sense.

If a driver wants to save energy, why waiting until there's a hill or drag racing to save?
 
Yeah, maybe. But it's a known thing. That is, when it's cold out and I want to stay comfy, I have the heat on, knowing full well my overall efficiency and range will be impacted. If I want to hypermile for some reason, then the heat comes off. I can't think of anything in particular I'd like the car to do to automate things. For example, I haven't noticed a performance hit for having the heat on, though I'm a pretty conservative driver, so I might not notice.
 
It costs more but a full heat pump with using the battery coolant would be most efficient no? Resistive heat always worse,

Yes a heat pump is about 3x more efficient than straight resistive heating. I think we'll see Tesla switch from AC to heat pump sometime in the future. It would increase range at any temperature > -10 F.

It would increase the cost of the car by a decent amount.
 
Yes a heat pump is about 3x more efficient than straight resistive heating. I think we'll see Tesla switch from AC to heat pump sometime in the future. It would increase range at any temperature > -10 F.

It would increase the cost of the car by a decent amount.

For quick heat, heat pump is just too slow!

In freezing weather, waiting for the heat pump to warm up is like an eternity!
 
For quick heat, heat pump is just too slow!

In freezing weather, waiting for the heat pump to warm up is like an eternity!
Well, since Tesla would still have to include the resistive heat for extreme cold, they could offer compromise - resistive heat while heat pump kicks in...... Best of both worlds. Quick heat up, and low ongoing cost of energy.
 
Does your commute long enough to require most of the battery?

If not, don't worry about it, just enjoy being warm. Forget about the battery.

yes. i drive 70 miles round trip and at least 100 miles daily.

Yes a heat pump is about 3x more efficient than straight resistive heating. I think we'll see Tesla switch from AC to heat pump sometime in the future. It would increase range at any temperature > -10 F.

It would increase the cost of the car by a decent amount.

yes but heat pumps are only as efficient as the amount of available humidity. the colder it gets, the less humidity there is. it's definitely a trade off.

Yeah, maybe. But it's a known thing. That is, when it's cold out and I want to stay comfy, I have the heat on, knowing full well my overall efficiency and range will be impacted. If I want to hypermile for some reason, then the heat comes off. I can't think of anything in particular I'd like the car to do to automate things. For example, I haven't noticed a performance hit for having the heat on, though I'm a pretty conservative driver, so I might not notice.

thanks for all of the constructive replies. again, this isn't an issue of performance, but efficiency.
 
Would adaptive controls improve the efficiency of the battery when using HVAC to heat the cabin? Many ICE vehicles, especially those with low power output, have the ability to disengage the AC while accelerating, returning power to the engine. If there was an option for "Adaptive Heating", that would disable the heater for things like accelerating, climbing a hill or anything that requires a power output of greater than a certain output of the wh/mi, do you think the efficiency would increase?

Would this be a better option than just driving with the heat off or really low?

Ok so using the heater doesn't decrease the "battery efficiency". It affects your overall "driving efficiency" as far as the Wh/mile is concerned.

I have a problem with your test of turning on and off the heater while drive and seeing a big decrease in Wh/mile though. If you for example drive 30 miles without the heat and get a certain Wh/mile value, then reset the trip counter(or not), turn on your heat for the next 30 miles, you will definitely see a spike, BUT that is because the heater has to go max output right away to get the cabin up to your set point. As has been stated many times before, short trips are worse for your driving efficiency because the heater is doing a lot more work for the distance traveled. On longer trips the average heater use goes down the more miles you drive.

The other issue is that the heater usage over distance is also a function of speed. At slower speeds the percentage of heater usage in your driving efficiency is higher than the percentage at higher(highway) speeds.

The heater uses a max of ~7kW in the model 3. So I guess there is a technical possibility that when you are commanding max output from the motor that you might be restricted by 7kW but is that 7kW really making that much of a performance hit?

Turning on/off the heater in cold outside temperatures is also probably going to be a worse option as your normal heat losses can end up lowering the cabin temperature such that the heater will have to use more power in a burst in order to get the cabin temperature back up.

The heater usage is not affecting the efficiency of any particular component, like the motor under power or in a regen condition.
 
so again, and maybe i'm using the wrong terminology, but i'm not talking about the performance of the motor/battery, but the throughput of the wh/mi. my recent road trip never saw wh/mi below 300 and whenever i left a SC station, it took 40% of the battery to return from around the 400s to that 300 range. cabin was set at 67, seat heater at 2, outside temperature hovering around 40° and traveling at 75mph.

with my 30 mile commute each morning, and the heat off (but seat heater on), i see wh/mi at 250 wh/mi and below. 15-20 miles of this commute has no stop-and-go, short of a few lane changes and the usage goes even lower during stop-and-go.

is the reading of the wh/mi bunk? is it something not to worry about? i'm definitely one of those people that are like "just drive the car" but after this last road trip, i'm genuinely curious. when i see i'm only getting ~10-15 miles of range per 10% of battery, it's a bit concerning.
 
so again, and maybe i'm using the wrong terminology, but i'm not talking about the performance of the motor/battery, but the throughput of the wh/mi. my recent road trip never saw wh/mi below 300 and whenever i left a SC station, it took 40% of the battery to return from around the 400s to that 300 range. cabin was set at 67, seat heater at 2, outside temperature hovering around 40° and traveling at 75mph.

with my 30 mile commute each morning, and the heat off (but seat heater on), i see wh/mi at 250 wh/mi and below. 15-20 miles of this commute has no stop-and-go, short of a few lane changes and the usage goes even lower during stop-and-go.

is the reading of the wh/mi bunk? is it something not to worry about? i'm definitely one of those people that are like "just drive the car" but after this last road trip, i'm genuinely curious. when i see i'm only getting ~10-15 miles of range per 10% of battery, it's a bit concerning.

There might be a terminology and definition issue here... The cabin heater will not affect the efficiency of any hardware. It will affect the overall energy used vs miles driven(Wh/mile in the trip meter). It will affect this the same as you driving at different speeds, or having your windows rolled down while driving at highway speeds thereby increasing drag, or using your brakes instead of regen...etc etc etc.

You just have to understand what is going into that Wh/mile number...it is all the energy that the car is using while not in PARK. There are ways to game that number however if wanted too....whenever you stop at a stoplight, put the car into park. That will make any energy used while in park not end up in the trip meter. It will still be using energy of course.
 
...is the reading of the wh/mi bunk? is it something not to worry about?...

It is good to know what's an individual driver's energy consumption is.

Energy consumption is dependent on a driver's driving style as well as environmental factors.

So, the comparison has to be on the same exact factors: The same distance of travel, same temperature, same wind speed...

If the energy consumption is out of ordinary, then maybe there's a new factor introduced such as heater on while stuck in standing still traffic for 30 minutes. Although the car does not move, the consumption from the heater still counts so, more consumption with the same miles means more Wh/mile.

That's nothing to worry about as long as you can get home without being stranded on the road.

In general, there's nothing to be concerned about energy consumption as long as a driver knows there's enough energy to get to the destination.

However, for those who want to improve their range, then there are energy consumption factors to look at:

1) Bigger rims mean bigger energy hogs: Make sure it's the one that comes with standard base model.
2) Faster speed means faster energy depletion: Slow down
3) Head Winds: It's like speeding
4) Heater: Worse than Air conditioning
5) Air conditioning: Not as bad as heater but still significant.
6) Use Autopilot as much as possible to avoid human lead foot and human's overspeeding tendency.

Since 2012 until now, I've found that if I keep the speed limit and avoid HVAC/Heater, I can arrive at the destination by adding 50 more battery miles to the road distance. For example, if my trip is 200 miles, I don't drive away until the battery gauge says 250 miles.

Some people need more, like for a 100 mile trip, they won't leave until their battery gauge says 180 miles--an extra 80 mile buffer.

You just know what your driving style is and add extra buffer miles before leaving.