Dissecting phantom drain estimates

[mkhuffman]

I especially like it because it recognizes that ALL vehicles use energy when sitting idle. Even my 25 year old ICE 4Runner loses battery when in the driveway.

Yeah but my Mach-e can sit for days, weeks, without losing any measurable HVB charge. The car is using the LVB for its "metabolism" and will charge it from the HVB when the LVB gets low, but there is no comparison. 3 kW per day vs basicly zero. To me, it is a huge problem and it is very interesting the legacy car companies have figured it out but the start ups have not.

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[VSG]

You skipped my context, and my point. The next paragraph in my post, which you didn't quote, says (emphasis added):

When your vehicle is sitting idle, it is actually doing things. With the Rivian, there's a question of whether it needs to be doing these things or not (e.g. phoning home with data dumps). There's a question of whether hardware or software is making the vehicle do things when it shouldn't (e.g. when a seat belt is left buckled). And there's a question of whether the amount of power used to do some of these things is reasonable (does gear guard really take a lot of power?).

So if your Mach-e isn't losing energy, then it isn't doing anything when sitting idle. Simple as that. It's EASY to make a car that does nothing while parked.

Rivian on the other hand is *deliberately* and *knowingly* doing some things when the vehicle is idle. It's not a matter of all the energy disappearing due to some unknown cause.

Some of those tasks, like harvesting data, help the company even if they don't necessarily help you directly, so while you may characterize the energy *use* as unacceptable Rivian might characterize it as necessary and profitable.

I see 60W of always-on power to be understandable when you compare it to the other things I listed in my post. That's on the order of what a laptop draws while in use, and there are a lot more electronics in a Rivian than in a laptop.

Sure I'd like that to be less, and sure Rivian should continue to identify sources of *unintended* energy use (like power converters that draw energy even when there is no load, much like your phone charger) but it's hardly outrageous given what we know the vehicle is doing while idle. And Rivian has made noticeable progress over the past year towards reducing this.

How low do you think the power usage should be? 0W is not realistic if you expect your vehicle to have more functionality than a rock while it's parked. I guess Rivian could flip the off switch so we would have to boot up our vehicles every time we got into them (which, like a hard reset, takes many minutes), or just let the batteries freeze when they get too cold instead of trying to keep them at some minimally acceptable temperature, but every little bit of functionality has a cost in terms of energy use.

 

[mkhuffman]

You skipped my context, and my point. The next paragraph in my post, which you didn't quote, says (emphasis added):

So if your Mach-e isn't losing energy, then it isn't doing anything when sitting idle. Simple as that. It's EASY to make a car that does nothing while parked.

Rivian on the other hand is *deliberately* and *knowingly* doing some things when the vehicle is idle. It's not a matter of all the energy disappearing due to some unknown cause.

Some of those tasks, like harvesting data, help the company even if they don't necessarily help you directly, so while you may characterize the energy *use* as unacceptable Rivian might characterize it as necessary and profitable.

I see 60W of always-on power to be understandable when you compare it to the other things I listed in my post. That's on the order of what a laptop draws while in use, and there are a lot more electronics in a Rivian than in a laptop.

Sure I'd like that to be less, and sure Rivian should continue to identify sources of *unintended* energy use (like power converters that draw energy even when there is no load, much like your phone charger) but it's hardly outrageous given what we know the vehicle is doing while idle. And Rivian has made noticeable progress over the past year towards reducing this.

How low do you think the power usage should be? 0W is not realistic if you expect your vehicle to have more functionality than a rock while it's parked. I guess Rivian could flip the off switch so we would have to boot up our vehicles every time we got into them (which, like a hard reset, takes many minutes), or just let the batteries freeze when they get too cold instead of trying to keep them at some minimally acceptable temperature, but every little bit of functionality has a cost in terms of energy use.

I don't need my car to do anything when I am not in it. And certainly not anything that requires 3 kW per day. Seriously.

I can query my MME using the Ford app any time and see what the HVB SoC is, and it will update. WTH else do I need? Sure GG is cool, but if is turned off, then why doesn't the vampire drain also go away? People are turning everything off and seeing no change in the vampire drain. That is just stupid, IMO. If everything is off, vampire drain should be zero. Zero.

 

[emoore]

I don't need my car to do anything when I am not in it. And certainly not anything that requires 3 kW per day. Seriously.

I can query my MME using the Ford app any time and see what the HVB SoC is, and it will update. WTH else do I need? Sure GG is cool, but if is turned off, then why doesn't the vampire drain also go away? People are turning everything off and seeing no change in the vampire drain. That is just stupid, IMO. If everything is off, vampire drain should be zero. Zero.

I do think Rivian can get their drain down but not to what the Mach e or other legacy cars are at. More like what Tesla is at. I’d rather spend some energy keeping the battery within temp vs having zero drain.

 

[Smashby]

There’s much discussion about phantom drain so, like you, I did my own study. I’m not an engineer, mathematician, or anything like that so my method is pretty simple - but I believe quite accurate (over time). I own both a Tesla MX and a Rivian R1T and use the same method to determine phantom drain on both. My method is simple.

Any time I know I’m NOT going to drive the vehicle for several days, I simply make a note of the SOC and date/time (screenshot actually). Then, the next time I drive the car I do the same so I can see how much the SOC went down during a set time (while vehicle is parked in garage). I assume the MX (100D) has a 100kwh battery and R1T has 135kwh battery. Then I just do the simple math based on these numbers (I.e. used X percent in X hours to sleep). Both vehicles are set to similar settings (no proximity lock, gearguard/sentry, etc) and I keep the data in cumulative form (doing this on both cars since since May 2022).

I call it my car’s metabolism. It’s what it takes (the electrical draw) for the car to sit there in the garage appearing to do nothing. My 2018 MX has a metabolism of 21 watts. My 2022 R1T has a metabolism of 156 watts. I’m not sure why this is. I probably should revisit the numbers and recalculate them to include idle time only during the last 3 months or so (as opposed to 18 months) to try to determine if Rivian is making any progress on this. I keep hearing they are, so I should try to verify. BTW I love both these vehicles and never looked back after my first EV!

What App are you using to record this data? Thanks.

 

[HaveBlue]

It should use as much power as a cell phone while idle is my opinion.

I just had another thought!! Why don't we all opt out of the diagnostics and sharing options in the privacy screen on the car? Maybe it will sleep more.

<<Edit>> Whoa I turned off all the settings in the Data privacy screen and changed the proximity lock to off at home. Walked back in the house and checked the app and the car is sleeping. That's a first.

 

[tate16t]

This explains why I see traffic from my vehicle when connected to my home network.

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