Electrify America charging issues - More RAN stations because I don't want to deal with this nonsense.

[McMoo]

Well that must be it because the science is certainly simple enough. That covers the forum but with respect to the broader problem of widening BEV acceptance we must "Consider the intelligence of the average American and then ponder that half the population is dumber than that".

Engineer type answers don’t really help most people.

As a CPA, there’s the technical answer, code section references, and analysis that goes into memos and internal documents. Clients do not care about that. They want a practical answer that they can understand. They don’t care how it works in the background, they want to know how it impacts them and their situation.

All that matters to the average EV consumer is how far can I go on a charge and how much time does it take to add X number of miles when fast charging. Period. That’s it. No equations or calculations. I know these aren’t static numbers based on many variables but it’s the most relevant information for the average person.

Sponsored

 

[McMoo]

Pretty appropriate timing for this video.

 

[ajdelange]

You have yet to explain how MPGe (or Wh/mi or mi/kWh) can, in and of themselves, be a one to one correlation to miles per minute charging without taking into account the speed of the charger and the max rate the car can accept.

This is getting silly. I have posted the formula for charging miles per hour at leat 3 times and, of course, each time, the formula contains the thee relevant factors. Each time you come back and say I didn't consider all the relevant factors. So clearly you choose to ignore what I'm trying to explain to you and challenge me to prove what I never claimed.

You stated that a vehicle with 2x MPGe would charge 2X miles per minute. I've pointed out many examples where that is not true.

Do you know what ceteris paribus means?

If all I tell you is the Yamazuka GT3s gets 132 MPGe, and the Truckster QWZ is rated at 64 MPGe, can you tell me which one gets the most miles per minute (or hour) charging? Either at home on L2 or at a DCFC on the road?

No because a net search for a Yamazuka GT3s turns up nothing. More to the point here is that someone comparing the Telsa models to each other or the Rivian models to each other or the Rivian models to the Teslas can get a pretty good idea as to what relative charging times will be on a road trip. They will be directly proportional to the Wh/mi and, thus, inversely proportional to the MPGe. You may be incapable of doing this as indeed may be most but not all and it is for those folks I post. And I do it in the hope that it will get those who have the tools to appreciate what may be a new perspective on these matters.

[Edit]While it should be obvious, especially given the hint put forth by mention of ceteris paribus, one needs to use appropriate charging rates for each vehicle considered.

 

[ajdelange]

Engineer type answers don’t really help most people.

If someone posts "there is no correlation between Wh/mi or MPGe" I think that ill serves most people because it obviously isn't true. But that it isn't true isn't obvious to people who have no sense (engineers call it "the knack") of how electrical and mechanical things work. And unfortunately there is no way to explain why without going to some math. Now it has been suggested that the problem is that I in particular am unusually inept as a teacher and this may be the case but I can't think of any way to explain this without using math.

Clients do not care about that. They want a practical answer that they can understand. They don’t care how it works in the background, they want to know how it impacts them and their situation.

I think that's an unwarranted assumption. I'll bet you do have clients that want to understand how things work. I remember a conversation with a bank manager in which he mentioned that his bank was offering CD's with "continuous interest". Of course I wanted to know how it would work. How else would I be able to calculate the present value of a CD? He, of course, hadn't a clue how it worked other than to say he had to use a key labeled "e" on his calculator which revealed all.

All that matters to the average EV consumer is how far can I go on a charge and how much time does it take to add X number of miles when fast charging. Period. That’s it. No equations or calculations. I know these aren’t static numbers based on many variables but it’s the most relevant information for the average person.

As with your clients I'll point out that there are many who bought a BEV becuse of the tech aspect of it who are very interested in understanding as much of that tech as they can. At least that's what I thought at first but I have been very surprised at how few of them are manifest on this and similar forums. Maybe they are just smart enough to remain silent.

For those who don't want to do ANY calculations at all (and I've seen lots of people post declaring themselves to be in that set) be aware that the vehicle's navigation system will tell you as you drive how long you will have to charge at your next charging stop to reach the one after that or your destination. It does the calculations for you. For planning purposes ABRP (and other planning programs) will do the same thing but of course as it is a priori must make assumptions about driving conditions.

 

[ajdelange]

Do you have an EV? .... guess what’s going to be the most critical indicator of practical charging speed? Yup. MPGe.

See. There are others who understand!!!

 

[azbill]

Do you have an EV? If you do , you will probably know that 50kW chargers are by far the most common DCFC. For as long as this is the case, MPGe is going to be a very good indication of charge speed.
And heck, one day when every car has 350kW charging capability and 350kW charging stations are everywhere, guess what’s going to be the most critical indicator of practical charging speed? Yup. MPGe.

How many people know the flow rate of gas pumps in gallons per minute? Probably close to zero. Why? Because how much time you spend fueling a car is more a factor of the fuel efficiency (and the size of the tank). It’s the same here.

Two to three years ago I would have agreed that 50KW chargers were the most common DFDCs, but today that has changed. I have an EV and I live in Phoenix. Today in this area there are 5-6 EVGO DFDCs in the metro area and 1-2 ChargePoint DFDCs, all of those are 50-60KW. There are already 3 sites operational for EA in the metro areas, two sites have two 150KW chargers and two 350KW chargers. The third site has six 150KW chargers and two 350KW chargers. There are currently six new EA sights under various stages of contruction, at least two just need power turned on, and those each have four 150KW chargers.

Additionally, Tucson has two EVGO 50KW DFDCs and ten EA chargers of 150-350KW. My point is that the days of 50KW chargers seems to be numbered, I have only seen one new unit installed in the last 4 years at that level.

For level 2 charging, I do agree MPGe does directly affect the miles per minute since all of the vehicles are indeed recieving the same KW input. But for me the use of L2 is not valid for cross country travel, and that is where charging speed really counts. The second valid case is if you do not have a home charger, i.e. have an EV but live in an apartment.

As for gas pumps, there is a federal legal limit for passenger car gasoline/diesel of 10 gallons per minute. For big diesel trucks it is higher, 34 gallons per minute. I have a Saturn Sky with a 12 gallon tank, I can fill it in one minute, not counting the overhead of using my credit card and selecting the grade, etc. I also have a GMC pickup with a 26 gallon tank, and I can fill that in 2.5 minutes. An extra 90 seconds at the pump is not really an annoyance to me. In fact I almost always spend that 1-2 minutes cleaning my windshield.

 

[ajdelange]

For level 2 charging, I do agree MPGe does directly affect the miles per minute since all of the vehicles are indeed recieving the same KW input.

I wonder if it would help the situation to note that the 11.52 kW chargers on board Teslas and Rivians could also be specified as being .342 GPhe chargers. A Rivian with its estimated 75 MPGe economy would thus charge at .342*75 = 25.6 mph at full bore Level 2 whereas a Tesla X at 100 MPGe would charge at 34.2 mph. This is, of course, the same answer you get by dividing the kW capacity of the charger by the kWh/mi consumption of the car but it conceals the dreaded kW from the public much as we conceal the cm from it. The latter puts us right up there with Myanmar and Liberia but maybe people wouldn't be so confused.

Just as those of us who note such things soon come to realize that we are going to get about 85 kW from a Tesla V2 SC others would come to realize that they are going to get about 2.5 GPhe from a V2 station. Etc.

 

[ajdelange]

I should have added in the previous post that MPGe is clearly fine for determining the relative maximum Level 2 charging rates of the various models of cars that have the 11.52 kW chargers which seems to be evolving as the standard but it is not always the case that the car's internal charger will be taking the full 11.5 kW. For example, if the EVSE is on a 50 A circuit the charger will be allowed to take only 40 A not the full 48 the car can handle. It should be clear that in such a case the charging rate would be (40/48)*0.342 GPhe but even that level of math is going to overwhelm some here. As an aside I'll note I just had a message from eTrade which mentioned the Sharpe ratio and defined it using the "not too terrible math" (A-B)/C. Put that together with what I see here and that the US ranks 38th in math and 24th in science and I hope you all will understand why I worry.

 

[DucRider]

Do you have an EV? If you do , you will probably know that 50kW chargers are by far the most common DCFC.

I do, and 150 kW or higher are the most common DCFC in the US and have been for many years.

More to the point here is that someone comparing the Telsa models to each other or the Rivian models to each other or the Rivian models to the Teslas can get a pretty good idea as to what relative charging times will be on a road trip. They will be directly proportional to the Wh/mi and, thus, inversely proportional to the MPGe.

Not true.
Charging a Tesla on a V2 (most common) Supercharger will be slower than charging a Rivian (or Lucid, or Hummer, or Taycan, or ....) on an EA 350 kW charger will be slower and throw off the proportionality of the MPGe comparison. The Taycan is a prime example. By your logic a Taycan would charge at <60% of the speed (in miles per minute) than a Model S LR+, when in fact the Porsche will be faster.
MPGe cannot, in and of itself, be used to gauge charging speed in miles per time period. There is no direct relationship. Yes, you have given formulas. Yes, I understand them. Yes, they are true. But they are not relevant to the statement that MPGe can be used the gauge relative charging speeds.

For level 2 charging, I do agree MPGe does directly affect the miles per minute since all of the vehicles are indeed recieving the same KW input.

No, different vehicles have on board chargers with different specs. Many EVs are limited to 6.6 kW, a few have 3.3 kW, some have 11.5 kW. If you only use a 16A EVSE (or L1 charging), only then you could look at MPGe as a relative measure.

 

[azbill]

No, different vehicles have on board chargers with different specs. Many EVs are limited to 6.6 kW, a few have 3.3 kW, some have 11.5 kW. If you only use a 16A EVSE (or L1 charging), only then you could look at MPGe as a relative measure.

I understand that and should have stated approximately the same. Most of the L2 public chargers today are 6.6KW in my experience and nearly all newer vehicles have an internal capability at that level or higher.

 

[azbill]

Pretty appropriate timing for this video.

Someone else thinks like me, miles/min or km/hr, obviously he is in Europe. His cutoff of 75% is reasonable also. My Bolt starts to taper at 50%, but at 67% it really drops. That is where I usually want to stop a fast charge, unless there is a long leg to the next charger or a big hill to climb or a big headwind.

 

[Gshenderson]

I should have added

No, “adding” is that last thing you should be doing. Less is more.

Here, I’ll hand you your response...

 

[Gshenderson]

I think one very good and valid point made by AJ in this thread is the different mindset of charging an EV vs. gassing up an ICE. When gassing up, most people are going to want to fill it full. With an EV, it’s more about taking on just enough to get to the next destination with a charger. This is likely a counter-intuitive thing that traditional ICE drivers will need to adapt to over time. At least that was the case for me. The fact that most EV drivers will have cheaper charging at home will help make the shift based solely on economics. You don’t have that option with ICE.

 

[DucRider]

I think one very good and valid point made by AJ in this thread is the different mindset of charging an EV vs. gassing up an ICE. When gassing up, most people are going to want to fill it full. With an EV, it’s more about taking on just enough to get to the next destination with a charger. This is likely a counter-intuitive thing that traditional ICE drivers will need to adapt to over time. At least that was the case for me. The fact that most EV drivers will have cheaper charging at home will help make the shift based solely on economics. You don’t have that option with ICE.

Agreed, and worth pointing out that some potential adopters haven't grasped that they don't need to wait until they are at 1/4 "tank" (or so) and then fill up when they are out and about. Leaving home every day after topping off at night (to whatever level you are comfortable with) is something many have not considered when they lament the lack of public charging infrastructure.
There is, however, a large segment of the population that does not have the option of installing home charging (apartment dwellers, street parking with no driveway/garage, etc) and that is the next big hurdle in adoption. Workplace charging can help alleviate that, as well as building codes for multi-family housing requiring provisions for charging.

 

[Gshenderson]

Agreed, and worth pointing out that some potential adopters haven't grasped that they don't need to wait until they are at 1/4 "tank" (or so) and then fill up when they are out and about. Leaving home every day after topping off at night (to whatever level you are comfortable with) is something many have not considered when they lament the lack of public charging infrastructure.
There is, however, a large segment of the population that does not have the option of installing home charging (apartment dwellers, street parking with no driveway/garage, etc) and that is the next big hurdle in adoption. Workplace charging can help alleviate that, as well as building codes for multi-family housing requiring provisions for charging.

I agree. My current situation puts me in that category of people where home charging is problematic (I currently live in a condo and putting a charger in the garage is challenging, but not impossible). I have a public charging station a mile away, though, which is where I usually change my Tesla using a L2 J1772. They also have higher speed CCS/CHAdeMO option there, but I’m too cheap to buy the $500 adapter for my Tesla. So I usually just park my Tesla there overnight and walk back and get it the next morning. No big deal, and the exercise is good. Not to mention the charging is free.

Sponsored