remote start / pre-heating still uses up battery?

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oaklandish

New member
Joined
Feb 9, 2018
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2
My understanding was that part of the point of the remote-start feature was that it could be used to run the climate controls while the car is still plugged in, drawing power from the grid rather than the battery.

However, it doesn't seem to be working that way for me. A couple days ago, I did the remote-start, letting run for close to the full 20 minutes. Before that, the battery had been fully charged. (It was well past the estimated finish time and charge indicator light was doing the fast-blink indication.) The climate controls had been set on auto and ~75F the night before.

As soon as the remote-start activated, I noticed that the indicator light went back to charging (solid green), and stayed that way throughout the 20 minutes. Then, when I got in and turned on the car, before going anywhere, the battery graphic looked mostly full, with typical (for cold weather) range showing on the GOM, but my energy usage display looked like this:



This is a big chunk of battery used during that time if the point of remote-start is to take advantage of the power from my house instead of the battery. Or it is showing me energy from the battery *plus* what's drawn through the charge cord? (I do only have the OEM 120V cord.) Or perhaps this shows energy consumed from the battery but not subtracting out any charging that simultaneously went on at that time?

Whichever it is, 1 KWh for 20 minutes is (1000 / (1/3) ) = 3 kW on average during that time, which sure seems like a lot for a heater and fan, but maybe it isn't.

Does anyone have some experience or understanding that could shed light on this? Is my remote-start feature behaving correctly or not?
 
Do you have your car programmed for delayed charging? ...meaning when you plug it in during the day it has the delayed blinking green light until you say it should start charging (for off-peak charging)?

I'm wondering that if yes, that could explain why it wasn't drawing from the plug. (a theory anyway)
 
oaklandish said:
This is a big chunk of battery used during that time if the point of remote-start is to take advantage of the power from my house instead of the battery. Or it is showing me energy from the battery *plus* what's drawn through the charge cord? (I do only have the OEM 120V cord.) Or perhaps this shows energy consumed from the battery but not subtracting out any charging that simultaneously went on at that time?

Whichever it is, 1 KWh for 20 minutes is (1000 / (1/3) ) = 3 kW on average during that time, which sure seems like a lot for a heater and fan, but maybe it isn't.

1) Your heater can easily consume 6 kW or more, especially in the beginning (the first minute or 3).

2) If you are charging at 120V, your heater can easily pull more out of the battery than your EVSE can supply.

3) I do not know if running the heater (or anything/everything in the vehicle) only pulls from the battery, and the EVSE is "recharging" the battery (if that were the case, then "since last full charge" would show total consumption of heating. It *could* be simply the difference between what you used and what the EVSE supplied from the wall.

Test - do this two mornings in a row when the temps will be about the same :

A) Before starting the test (a1) set/verify charge rate {8A/12A} for 120V charging (a2) go to the car and set the controls to consume the lowest possible heat energy with heater running: (heat on, temperature about 10 degrees higher than outside {or the temp one higher than "LO" if it is really cold}, automatic setting OFF, fan speed at ONE).

B) Take note of the morning outside temp for reference (if it is 30 degrees warmer outside, the heater isn't going to work as much). And by "outside", I mean "just outside the driver's door": if parked in a garage, it's the garage temp. If parked on the driveway, it's the temp on the driveway. Also open the car and note what your estimated range is.

C) Do Remote Start ("Conditioning") for exactly 15 minutes (use an egg timer, or your phone) - then turn off Remote Start.

D) Go to car - start car, look at "energy consumed" screen (the one you posted a pic of). Write down how much energy consumed.

E) THE SECOND MORNING unplug the car from the EVSE before doing "Remote Start" (for the same amount of time). If the energy use is the same, either that screen shows energy consumed to precondition, even if some of (or all) the energy was actually pulled from the wall -OR- your car wasn't pulling energy from the wall the other time. If you have your car set to only charge at "non-peak" times and the "Remote Start" is done outside of the "non-peak" period, I don't think that the car will pull energy from the wall. Also, if your estimated range did change the same amount both two mornings (the difference between range shown before "Remote Start" and after RS), then electricity was NOT being pulled from the EVSE for Remote Start.

(The only reason you set the heater to "low temp" is to draw as little power as possible - hopefully not sucking up a huge amount of energy you might need during the day.)

The other way to test is to use a public (free, hopefully) L2 charging station, or a friend's 240V EVSE, that can charge at 3.3 kW.

First, figure out how much energy your heater is using *today*, *at current settings*. Get in the car and turn it on, wait for the main screen to boot. Look at your main driver screen, above the steering wheel, where you see mph and charge/discharge rates of the battery when driving (on the right side of the display, where the "KW" ball is). It should say 0kW (since you are just sitting in the car with everything off - radio, heater, etc). Now turn on the heater to maybe 5 degrees above ambient, and fan to "one" (slowest fan), and "auto" setting off. Does the "generating" icon/graphic on the right of the main display say you are using 1 kW? 2 kW? 4 kW? 6 kW? That will show you how much your heater draws.

Now drive to the 240V charging station, park. BEFORE turning off the car, set the heater to a setting that will draw about 2 kW (less than that supplied by the 240V EVSE, which should be 3.2 kW). Now, leave the heater settings "on" and turn off vehicle (which obviously stops the heater and fan), plug in, start charge. Walk away (let the car charge fully) - go get something to eat. Once the car is fully charged, come back and do a Remote Start. Make sure the green "Charging" light comes back on. Let the car "condition" for 15 minutes. Get back into car - start car, look at "energy consumed" screen (the one you posted a pic of). Look at how much energy consumed for "Climate Setting". If it is 0% (because all of the electricity came from the EVSE and none from the battery) - you know that the screen shows energy consumed *only* from the battery - any energy pulled from the wall is not reflected in the percentage. If it is over 1% then the screen shows energy consumed to precondition, even if the energy was actually pulled from the wall.
 
I thought this was an interesting question so I ran a little test.

My 2015 spark EV was left out all night where low temp this morning was 33 deg. F. It was moved into the garage this morning. The energy Info screen read 49-0-0, 12.6 kWh at the start of the test.

My 2016 Spark EV was left in the garage all night. The energy Info screen read 0-0-0, 0.0 kWh at the start of the test.

Garage temp this morning was 52 deg. F

I set the heaters in both cars to 72 deg. F, outside air and fan speed 1. The 2015 was not plugged in. The 2016 was plugged into an L2 EVSE at 3.3 kWh. Both cars were remote started. At the end of 20 minutes, the Energy Info screen in the 2015 read 48-3-0, 13.2 kWh. The Energy Info screen in the 2016 read 0-0-0, 0.0 kWh.

It looks like the 3.3 kWh L2 EVSE was able to provide sufficient power to match what the heater was drawing from the HV battery.

Tomorrow morning I am going to repeat the 2015 test with an L1 EVSE and the car set to charge at 12 amps.
 
I have the same problem with my 2014. I have an 240v L2 16amp charger. The remote start definitely uses the battery even while plugged in.

Maybe there is a way to remote start it, and have it restore the charge in time before you leave. It would at least give you a warmer car than if it hadnt run at all. At 3.3kw, it should be able to restore 1 kw in about 20 minutes. So, if you plan to leave at 8am, remote start at 7:20am. It should run for 20 minutes, then automatically turn off. I think it would then charge back up for 20 min and be fully charged and mildly heated at 8am.
 
LVSpark said:
I have the same problem with my 2014. I have an 240v L2 16amp charger. The remote start definitely uses the battery even while plugged in.

Maybe there is a way to remote start it, and have it restore the charge in time before you leave. It would at least give you a warmer car than if it hadnt run at all. At 3.3kw, it should be able to restore 1 kw in about 20 minutes. So, if you plan to leave at 8am, remote start at 7:20am. It should run for 20 minutes, then automatically turn off. I think it would then charge back up for 20 min and be fully charged and mildly heated at 8am.

My experience so far is that the L2 EVSE, operating at 3.3 kWh, will be sufficient to provide a 20 minute remote start to warm the Spark EV and still leave you with a full battery - given it was full before the remote start.
 
But it's totally outside temp dependent also.

If it's -5° F, the Climate Control may run at its '100%' power the during the whole Precondition, as seen on the Climate Control page.

I think the heater itself is rated at 3.3kW, so with the fan, rear window, seats, and background power usage, the total would be more than the EVSE can provide.

At around 30° F (?) the climate system will get the cabin warm quicker and back off on the power demand of the heater, allowing the EVSE to keep the battery topped up.
 
NORTON said:
But it's totally outside temp dependent also.

If it's -5° F, the Climate Control may run at its '100%' power the during the whole Precondition, as seen on the Climate Control page.

I think the heater itself is rated at 3.3kW, so with the fan, rear window, seats, and background power usage, the total would be more than the EVSE can provide.

At around 30° F (?) the climate system will get the cabin warm quicker and back off on the power demand of the heater, allowing the EVSE to keep the battery topped up.
Yes, you are probably correct. It doesn't get much colder than the low 30's here so I really do not know what would happen in much lower temperatures. I did roll down the windows and switched to outside air to try and prevent the heater's power consumption from slowing down as the cabin warmed up.

Yesterday morning, before I left for an early church meeting, I turned on the remote heat function 20 minutes before I left. It was nice to get into a warm car although, when I reached my destination 4 miles later, my trip meter showed 1.9 mi / kWh. Still, I really love my Spark EVs!
 
MrDRMorgan said:
Yesterday morning, before I left for an early church meeting, I turned on the remote heat function 20 minutes before I left. It was nice to get into a warm car although, when I reached my destination 4 miles later, my trip meter showed 1.9 mi / kWh. Still, I really love my Spark EVs!

Yes, I've noticed that as well - "Remote Start" energy seems to be included in energy use calculations, no matter where the energy came from. I always forget at the time, but I am tempted to get in the vehicle, drive off but only for about 900 feet or so, and turn the vehicle off. I'd wait 10 seconds then restart the vehicle and see what the miles/kWh would be upon arrival 3 miles later. But as I said, I always forget.
 
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