EPA range and efficiency of MME

[EVer]

Perhaps.

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[JCHLi]

This is where I keep getting stuck in comprehending the benefit. Isn't a heat pump just like same as a regular AC except it's bidirectional? Just because it's a heat pump doesn't make it any more efficient compared to AC when cooling.

Now maybe it's a more efficient unit in general but being a heat pump doesn't determine that.

 

[EVer]

Isn't a heat pump just like same as a regular AC except it's bidirectional?

Just because it's a heat pump doesn't make it any more efficient compared to AC when cooling.

Now maybe it's a more efficient unit in general but being a heat pump doesn't determine that.

Agreed. Even if the Model Y heat pump is somewhat more efficient than what they used as the air conditioner in previous models (which isn't necessarily true; maybe designing it to be reversible decreases efficiency somewhat), I think it would be difficult to see it in EPA ratings. HVAC is on for only 10% of the 5 cycle test, to which various weightings are then applied (the gritty detail: https://www.law.cornell.edu/cfr/text/40/600.210-12).

 

[dbsb3233]

The EPA ratings will be curious, but what I really care about are videos from actual drivers showing power consumption on the screen at various highways speeds. Hoping we might get some of those by early Oct.

Around home, whether it gets 3.5 miles/kWh or 3.0 is little more than curiosity, since I'll have way more than enough range around home either way. Anything better there is just bonus (saves a few bucks on the home electric bill).

But at 75 MPH on the highway, it's crucial as to whether it's even a consideration for road trips.

 

[polzovotel]

Agreed. Even if the Model Y heat pump is somewhat more efficient than what they used as the air conditioner in previous models (which isn't necessarily true; maybe designing it to be reversible decreases efficiency somewhat), I think it would be difficult to see it in EPA ratings. HVAC is on for only 10% of the 5 cycle test, to which various weightings are then applied (the gritty detail: https://www.law.cornell.edu/cfr/text/40/600.210-12).

I-Pace has a heat pump but the range is not impressive. Based on what I read, the heat pump will really help in a cold climate. I am in Austin, TX, so I have no problem with cold

 

[polzovotel]

The EPA ratings will be curious, but what I really care about are videos from actual drivers showing power consumption on the screen at various highways speeds. Hoping we might get some of those by early Oct.

Around home, whether it gets 3.5 miles/kWh or 3.0 is little more than curiosity, since I'll have way more than enough range around home either way. Anything better there is just bonus (saves a few bucks on the home electric bill).

But at 75 MPH on the highway, it's crucial as to whether it's even a consideration for road trips.

Agree, and EPA will give you some clue about this as well. Anyway, I am really waiting for the real numbers to show up.

 

[polzovotel]

One thing to note... MY/M3 drivers routinely report getting lower than EPA range. Why that is could be down to the way the ratio of highway to city driving that is used in EPA measurements vs actual driving habits, or actually a reflection on Tesla’s insistence to use the number as-is. So, don’t take that number from Tesla as gospel. Plenty of MY LR AWD drivers report average numbers closer to 300 Wh/mi, which would push the typical range closer to 225-250 mi. (ala MME standard range estimates). Also keep in mind Tesla recommends a sub-90% charge regularly to preserver battery life- their buffer is tiny.

It is possible that Ford will use a number that is more reflective of US driving habits (with a higher highway mix than EPA standards) and it’s also possible that the numbers could be higher pending final production. After all, the standard range MME has a battery approaching the size of the LR Model Y. Also, the MME has a larger buffer built in, which should help with battery longevity and allow the user to routinely charge to higher levels like 100%. The MME doesn’t appear to be a poorly designed car in terms of aerodynamics, either, so I am hopeful. I do wish manufacturers were required to give one number of pure city driving, and a number for pure highway, like for an ICE vehicle, to arrive at their “combined” number based on their use cases.

Even when I drove MY in my neighborhood, I got about 270-300 watt per mile. So with normal driving, + AC - realistically we are talking about 270-280 miles on a full charge. With additional people in the car and cargo - maybe 230.

I do agree with you that Ford may allow (like Volt) charge to 100% each time w/o affecting battery life. But still, 88 kWh usable battery will drive you fewer miles per kWh than Tesla MY 73kWh. MME seems to be overall 20% less efficient if Ford will not change the specs. And while I do not really care about that when I charge at home (1$ more per charge - not a big deal), I do care about this if I charge on the road as it will take roughly 20% more time for charging as well.

 

[SD_Solar]

I-Pace has a heat pump but the range is not impressive. Based on what I read, the heat pump will really help in a cold climate. I am in Austin, TX, so I have no problem with cold

Actually, in real cold the heat pump will be of very little help.

I have a 2019 Leaf SL+ that has a heat pump and it’s pretty efficient at temps in the 45F to 25F. But in real cold say below 15F the heating system reverts back to straight resistance heating --- there are just very few BTU in the air at that temp to pump into the heating system.

 

[EVer]

that makes no sense; your units are hosed. At full power it may use 4kW continuous. I doubt the model 3 uses as much as the model x; there is less volume to heat.

 

[bullshark]

Pretty sure MME has no heat pump, otherwise it would show on the dealer training files. This is also my concern since I live in Canada.

 

[JCHLi]

Do you think the whole 20% reduction comes just from running the heater, or are there other factors? From past experience, I've noticed in really cold climates the Lithium ion batteries I've used drain super fast.

 

[EVer]

Do you think the whole 20% reduction comes just from running the heater, or are there other factors? From past experience, I've noticed in really cold climates the Lithium ion batteries I've used drain super fast.

Lithium ion batteries discharge (voltage decay) faster as ambient temperature decreases, even with constant load.

Even when it’s “cold” (which around here is rarely below 40°F in the morning), I tend to wear a coat rather than blast the heat (I don’t like hot air blowing on me and I’ll probably want a coat when I’m out of the car anyway), but battery life still suffers.

If you live in a climate where it’s significantly cold, you have to contend with both cabin heat and even more pronounced voltage decay. Pre-heating a plugged in vehicle is helpful.

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