[yozhbk]

Originally Posted by eelnoraa

This is 1.18mi/kWh, which is some of the lowest number I have seen. Maybe I ask if these are all very short trips, like 1-2 miles? I found if you do many shorts trips with a down time in between, each trip get very inefficient in EV mode.

If you really average out to 1.18mi/kWh, and $0.3/kWh, and say $4/gal for gas. Using 22MPG as assumption, ICE is definite a lot more cheaper for you. cost per mile is $0.17 for ICE, and $0.3 for EV (including 14% L2 charge lost). NO reason to charge in your case.

Same situation for me. I average to 2mi/kWh, 22MPG. Gas is $4.7, electricity is $0.5. I am looking at $0.21/mile for ICE, $0.3/mile for EV as of today. so I am not charging at home. I only charge at work now.

Yes very short trips, 1-5 miles most of the time, and thats round trip. If my trips worked I would show more. But for instance morning run to HS is 3.2 miles round trip. Trip to train about 2 miles. Little trips that add up to a lot eventually….
And usually filled with stop sights and lights and lots of stupid small streets traffic.


Wow .5 for kW? And I thought we had bad prices here, the gas right now is actually 3.29$ for regular and 3.99 premium. Havent been to gas station with this car so far.
Thats another good question, whats the gas recommendations? I see it says 89/91 on the cap.

[nZtiZia]

Originally Posted by yozhbk

Thats another good question, whats the gas recommendations? I see it says 89/91 on the cap.

as posted
89 minimum
91 recommended

[yozhbk]

Ok so I was a little off, its 195 miles and its showing about 8% left so lets say 200 miles with 135 kW charged. About 1.48 ? Still not great I guess.

[jad03060]

It can take a fair amount of energy to warm the vehicle, especially if you're using seat, steering wheel, mirror, arm rests, and rear window heaters...remember, all of that is electrical, along with the cabin heat. Throw in maybe it's early or later, and you may have the lights on, too. If you're going to be doing lots of short trips, you may want to look into a battery maintainer, as you'll be putting a lot of stress on the 12vdc system that may not be fully replaced on a regular basis.

[yozhbk]

Originally Posted by jad03060

It can take a fair amount of energy to warm the vehicle, especially if you're using seat, steering wheel, mirror, arm rests, and rear window heaters...remember, all of that is electrical, along with the cabin heat. Throw in maybe it's early or later, and you may have the lights on, too. If you're going to be doing lots of short trips, you may want to look into a battery maintainer, as you'll be putting a lot of stress on the 12vdc system that may not be fully replaced on a regular basis.

Are you saying this because of the use of electric ? and 12vdc does not get regenerated ? Because i never had an issue before like this due to short trips.

[TurtleBoy]

Originally Posted by yozhbk

Are you saying this because of the use of electric ? and 12vdc does not get regenerated ? Because i never had an issue before like this due to short trips.

There are differing opinions on that. I think you will be fine. In fact your battery should be charging more on those short trips than if you were taking longer highway drives but that is assuming the 45e uses the same logic for charging the 12v battery that it uses in its other models.

[eelnoraa]

Originally Posted by yozhbk

Ok so I was a little off, its 195 miles and its showing about 8% left so lets say 200 miles with 135 kW charged. About 1.48 ? Still not great I guess.

This is my estimate of your stat. But your car is too new, the "sample" same is too small.

Keep in mind, when charging, there is a charge lost of 14% for L2, and 21% for L1 from my observation So whatever the "electricity used" column said, more are drawn from plug.

Using your input from above, $3.99 for gas, $0.3 for kWh. I got $0.22/mile for ICE, and $0.23/mile for EV (including 14% charge lost). Under this small margin, I i will still charge at home with L2. Because i believe if you do this kind of short trips with ICE, MPG will be below 17.8.

Oh, and maybe I ask wheel/tire setup? I am trying to see if there is correlation between the significant difference between mi/kWh to wheel/tire setup.

[yozhbk]

Originally Posted by eelnoraa

This is my estimate of your stat. But your car is too new, the "sample" same is too small.

Keep in mind, when charging, there is a charge lost of 14% for L2, and 21% for L1 from my observation So whatever the "electricity used" column said, more are drawn from plug.

Using your input from above, $3.99 for gas, $0.3 for kWh. I got $0.22/mile for ICE, and $0.23/mile for EV (including 14% charge lost). Under this small margin, I i will still charge at home with L2. Because i believe if you do this kind of short trips with ICE, MPG will be below 17.8 as your indicate.

Wow thank you. Yeah need a bigger sample. What sheet you used ? I want to use that later when I have a bigger sample?

[Scientifix]

Originally Posted by yozhbk

Ok so I was a little off, its 195 miles and its showing about 8% left so lets say 200 miles with 135 kW charged. About 1.48 ? Still not great I guess.

As I mentioned in another reply, 50 mpge is what is claimed by BMW. And this means with 33.7 kwh of electricity (energy equivalent of 1 gallon of gas) gives 50 miles of distance travelled.
So 50/33.7 is 1.48 miles per kilowatt. So it's not bad in fact it's exactly what 45e is rated at. And typically very rarely you get what the manufacturer rates their vehicles at when it comes to EV range and efficiency (true for mpg in ICE world as well)

[eelnoraa]

Originally Posted by Scientifix

As I mentioned in another reply, 50 mpge is what is claimed by BMW. And this means with 33.7 kwh of electricity (energy equivalent of 1 gallon of gas) gives 50 miles of distance travelled.
So 50/33.7 is 1.48 miles per kilowatt. So it's not bad in fact it's exactly what 45e is rated at. And typically very rarely you get what the manufacturer rates their vehicles at when it comes to EV range and efficiency (true for mpg in ICE world as well)

why? BMW advertised 31 miles range with usable battery capacity of 17.1kWh, so BMW is advertising 1.81Mi/kWh, right?

Maybe rare, but it seems 45e is well beyond 1.48. I would guess average will be above 1.81 too, but my sample size isn't big.

[robg]

Originally Posted by Scientifix

As I mentioned in another reply, 50 mpge is what is claimed by BMW. And this means with 33.7 kwh of electricity (energy equivalent of 1 gallon of gas) gives 50 miles of distance travelled.
So 50/33.7 is 1.48 miles per kilowatt. So it's not bad in fact it's exactly what 45e is rated at. And typically very rarely you get what the manufacturer rates their vehicles at when it comes to EV range and efficiency (true for mpg in ICE world as well)

I think its a bit more convoluted than that for PHEVs; as i understand it, the mpge numbers quoted for plugin hybrids represent a combined figure for both gas and battery usage. They appear to use a distance of 100 miles to calculate this figure
https://www.fueleconomy.gov/feg/Find...n=sbs&id=42807

[jad03060]

Originally Posted by yozhbk

Are you saying this because of the use of electric ? and 12vdc does not get regenerated ? Because i never had an issue before like this due to short trips.

If you make lots of short trips, yes, the 12vdc system may not get fully charged. This is true for both the ICE and the PHEV. 12v system is in theory maintained while actively charging on the EVSE, or when there's an excess capability while driving. The electrical load can be substantial when the vehicle is trying to provide lots of heat from a cold-soaked condition while the heaters are running full tilt and your lights are on. Regeneration only can produce so much power, and the DC-DC converter may not be able to keep up initially, and then, you park, things cool off, and you do it again. I've had this happen on my 45e, and it happened with my previous ICE BMW. The vast majority of my trips are less than 3-miles, and many are barely 1/2-mile. I used to walk to many of them, but cannot do that any more, plus, there's lots of traffic and few sidewalks, so it's not particularly safe doing it.

The ICE versions of BMW use a clutch on the alternator, and it allows the state of charge on the AGM battery to often be less than 100%. The PHEV's DC-DC converter requires the HV system to be on, and that only happens when in READY state, or actively charging. If you plug in when you get home, and it doesn't need to charge much, not much gets into the 12vdc system, either during that potentially short time. The DC-DC power supply doesn't seem to have a huge excess capacity, IOW, it can run normal functions, with some smaller amount available to recharge versus maintain the 12vdc system. It's worse in the winter when all batteries have degraded capacity.

If you regularly drive a decent distance, you may never experience this. If your regular use is short trips, you might, as you might with an ICE as well. What that magic distance is, I've not yet discovered, but it appears to be more than I regularly use mine!

[Scientifix]

Originally Posted by robg

I think its a bit more convoluted than that for PHEVs; as i understand it, the mpge numbers quoted for plugin hybrids represent a combined figure for both gas and battery usage. They appear to use a distance of 100 miles to calculate this figure
https://www.fueleconomy.gov/feg/Find...s&id=42807

Oh I didn't know this is how calculate for PHEV!
0.1 gallon / 100 mi of gas + 63 kwh/100 mi?
I don't even understand this equation

If you use 0.1 gallons that will reduce the overall 33.7kwh/100 mi to 33.7-0.1*33.7 which is 30.33kwh. But why plus a 63kwh/100mi??

Can someone who understands this please explain?

[TurtleBoy]

Originally Posted by Scientifix

Oh I didn't know this is how calculate for PHEV!
0.1 gallon / 100 mi of gas + 63 kwh/100 mi?
I don't even understand this equation

If you use 0.1 gallons that will reduce the overall 33.7kwh/100 mi to 33.7-0.1*33.7 which is 30.33kwh. But why plus a 63kwh/100mi??

Can someone who understands this please explain?

The 63kwh is not a constant, it is different for every vehicle. I think it is used on battery size and range.

[yozhbk]

Ok, so this morning I did try preconditioning for the first time and I'm a bit confused on how it works or what it supposed to do.

So I put in for 7:15am departure, as I understand the conditioning turned on 30 min before that ? When I go to the car around 7:17 the heat and my seat as well as wheel were hot and it was all going, (not the passenger seat ?). Anyway, I unplugged the L2 charger before getting in the car and when I got in it was all still running, is this what supposed to happen ? I'm supposed to turn it off my self when I get in ? Cuz that seems like its still wasting electricity after unplugged..

[TurtleBoy]

Originally Posted by yozhbk

Ok, so this morning I did try preconditioning for the first time and I'm a bit confused on how it works or what it supposed to do.

So I put in for 7:15am departure, as I understand the conditioning turned on 30 min before that ? When I go to the car around 7:17 the heat and my seat as well as wheel were hot and it was all going, (not the passenger seat ?). Anyway, I unplugged the L2 charger before getting in the car and when I got in it was all still running, is this what supposed to happen ? I'm supposed to turn it off my self when I get in ? Cuz that seems like its still wasting electricity after unplugged..

Sounds like all worked as it should have. The passenger seat doesn't heat since there is no passenger. You are heating the vehicle, not wasting electricity, just turn it off or down if you don't need it.

[eelnoraa]

Originally Posted by Scientifix

Oh I didn't know this is how calculate for PHEV!
0.1 gallon / 100 mi of gas + 63 kwh/100 mi?
I don't even understand this equation

If you use 0.1 gallons that will reduce the overall 33.7kwh/100 mi to 33.7-0.1*33.7 which is 30.33kwh. But why plus a 63kwh/100mi??

Can someone who understands this please explain?

First, I think MPGe is just a simple a comparison to see which vehicle is more efficient in term using less energy to complete the “test course”, if you will, the EPA defined. For pure ice and pure EV, it is simpler, because there is one type of energy involved. With PHEV, it gets complicated because what portion of the test course is done in EV vs ICE is not well defined. There is probably no good way because the EV portion will and should depend on the EV range (battery size). So take mpge for PHEV as grain of salt.

For 45e, let’s give a shot to see what EPA did here.

Assumption:
1. Ice combined mpg: 20, or 5gal/100miles
2. EV MPGe: 31miles/17.1kWh, using 33.7kWh=1gal, we get EV MPGe = 61.1MPGe, or 1.63galE/100miles.

To archive 50MPGe or 2galE/100miles, as claimed by EPA, let’s estimate EV and ICE portion in term of percentage, x, here.

5x + 1.63(1-x) = 2, => x = 0.11, let’s call it 0.1 or 10%

I think this is where that 0.1 gal in the epa chat is from. This means if you do 10% driving with ice and 90% in EV, you get 50MPGe. But then we should ask ourselves, why 10/90 split? Seem arbitrary to me.

[LarsOtium]

Originally Posted by eelnoraa

First, I think MPGe is just a simple a comparison to see which vehicle is more efficient in term using less energy to complete the “test course”, if you will, the EPA definitely. For ice and EV, it is simpler, because there is one type of energy involved. With PHEV, it gets complicated because what portion of the test course is done in EV vs ICE is not well defined. There is probably no good way because the EV portion will and should depend on the EV range (battery size). So take mpge for PHEV as grain of salt.

For 45e, let’s give a shot to see what EPA did here.

Assumption:
1. Ice combined mpg: 20, or 5gal/100miles
2. EV MPGe: 31miles/17.1kWh, using 33.7kWh=1gal, we get EV MPGe = 61.1MPGe, or 1.63galE/100miles.

To archive 50MPGe or 2gal/100miles, as claimed by EPA, let’s estimate EV and ICE portion in term of percentage, x, here.

5x + 1.63(1-x) = 2, => x = 0.11, let’s call it 0.1 or 10%

I think this is where that 0.1 gal in the epa chat is from. This means if you do 10% driving with ice and 90% in EV, you get 50MPGe. But then we should ask ourselves, why 10/90 split?

Dude, you're sapping all the joy out of my 45e!

(Just kidding, but your math makes my head hurt a little. )

[nZtiZia]

Originally Posted by yozhbk

Ok, so this morning I did try preconditioning for the first time and I'm a bit confused on how it works or what it supposed to do.

So I put in for 7:15am departure, as I understand the conditioning turned on 30 min before that ? When I go to the car around 7:17 the heat and my seat as well as wheel were hot and it was all going, (not the passenger seat ?). Anyway, I unplugged the L2 charger before getting in the car and when I got in it was all still running, is this what supposed to happen ? I'm supposed to turn it off my self when I get in ? Cuz that seems like its still wasting electricity after unplugged..

normal operation.

i scheduled preconditioning for 5:50am departure M-F. I notice it begins around 5:20, so 30 minutes prior to the departure time. I actually don't leave until 6:10, so it's not running anymore by the time I get in. I start the car and drive away.

in your case above, it probably hadn't timed out yet by the time you got in (it runs for 30 minutes). I don't know what your HVAC settings are, but if that happened to me, I would just let it run, start the car and go. with HVAC on AUTO, it knows what to do.

[Scientifix]

Originally Posted by eelnoraa

First, I think MPGe is just a simple a comparison to see which vehicle is more efficient in term using less energy to complete the “test course”, if you will, the EPA defined. For pure ice and pure EV, it is simpler, because there is one type of energy involved. With PHEV, it gets complicated because what portion of the test course is done in EV vs ICE is not well defined. There is probably no good way because the EV portion will and should depend on the EV range (battery size). So take mpge for PHEV as grain of salt.

For 45e, let’s give a shot to see what EPA did here.

Assumption:
1. Ice combined mpg: 20, or 5gal/100miles
2. EV MPGe: 31miles/17.1kWh, using 33.7kWh=1gal, we get EV MPGe = 61.1MPGe, or 1.63galE/100miles.

To archive 50MPGe or 2galE/100miles, as claimed by EPA, let’s estimate EV and ICE portion in term of percentage, x, here.

5x + 1.63(1-x) = 2, => x = 0.11, let’s call it 0.1 or 10%

I think this is where that 0.1 gal in the epa chat is from. This means if you do 10% driving with ice and 90% in EV, you get 50MPGe. But then we should ask ourselves, why 10/90 split? Seem arbitrary to me.

Wow Wonderfully explained! Yes there's a slider scale with 5mpge on one end (ICE) and 61.1mpge (EV) at the other end. Move the slider to a point where you get 50mpge and see what you get? Yes why arbitrarily pick 50 for that?

[yozhbk]

Originally Posted by nZtiZia

normal operation.

i scheduled preconditioning for 5:50am departure M-F. I notice it begins around 5:20, so 30 minutes prior to the departure time. I actually don't leave until 6:10, so it's not running anymore by the time I get in. I start the car and drive away.

in your case above, it probably hadn't timed out yet by the time you got in (it runs for 30 minutes). I don't know what your HVAC settings are, but if that happened to me, I would just let it run, start the car and go. with HVAC on AUTO, it knows what to do.

That makes sense, I should put it 5-10 min before I leave. Thanks.

So the automation for the heating of passenger seat with preconditioning and with just automation is based if passenger seat is occupied, that's good to know.

[TurtleBoy]

Originally Posted by yozhbk

That makes sense, I should put it 5-10 min before I leave. Thanks.

So the automation for the heating of passenger seat with preconditioning and with just automation is based if passenger seat is occupied, that's good to know.

It won't heat the passenger by default but you can code it to do so if you need it. Personally I think if you have the cabin precondition it will receive some warmth from that and the passenger can just turn on the seat heaters if needed.