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I calculate that with 12 hours daylight 7000m2 of solar would charge around 15 i4 s from 0-100%. Is that right?! That’s a bit scary in terms of area of pvs required to power ev motor cars.
There are a lot of variables, but let's look at it this way. Let's consider a charging box with an incorporated battery fed uniquely by solar panels. You plug your i4 that is down to 10%, and you charge it. It starts at 200kW, but the curve goes down as the battery charges up, and overall, tests have shown that you'll get to 80% after about 30 minutes, after taking in from 10% to 80%, or 70% of your 80.7kWh, so 61kWh. Let's say that that box is on a fairly well used station where there is no line up for open chargers, but where over the 12 hours of sunlight, on average it is charging 50% of the time. So since it took you 30 minutes to take in your 61kWh, on average the box will be idle for another 30 minutes before somebody else connects; thus, the box must be able to dish out 61kWh per hour, or 61kW.

If your solar panels have the same efficiency as mine, since my 64m2 provide 12.3kW, 61kW would require 5 times 64m2, so 320 m2. Of course, the 61kW will be too weak to provide the instant power your car will initially draw, but that's why there needs to be a battery to stock the power to give you the big current when you need it and to recharge to prepare for the next car after you leave and nobody uses it for a while.

So let's imagine now a station with, say 20 charging spots, fully covered, where each spot is about 2.5 m wide by 6m long (your i4 is 1.85m wide by 4.8m long so it will fit just, plus and overhang of 3m for the roadway coming into the charging spots. Covering the charging area with solar panels requires 450m2, or only 1/14 of the capacity necessary to feed all the charging boxes (6400m2).

On the other hand, considering the biggest Gas Station/Convenience store in Texas (and possibly the world), the Buc'ees in New Braunfels, Texas; it has a 6700m2 store with fast food, toilets, and basically snacks retail, and 60 gas pumps. So a smaller scale version of that for our 20 charging spots above could have, say, a 2200m2 store, and the 450m2 covered area for the 20 charging spots, total 2650m2 of roof/solar panels, so the solar panels would provide about 40% of the energy required to feed the charging spots.

I agree that it's not really conceivable to have 100% of the charging energy provided by the solar panels, especially since there will be rainy days where the solar panels operate at much reduced power; but it can be argued that with today's technology (the solar panels efficiency are increasing every day), you can have re-charging stations where solar panels provide a substantial fraction of the total energy required.
 

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My wife’s new Sonata hybrid has a solar roof. It only adds about 2-3 miles a day of ‘free’ driving. It’s more useful for powering accessories when you’re idling or parked.
 

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My wife’s new Sonata hybrid has a solar roof. It only adds about 2-3 miles a day of ‘free’ driving. It’s more useful for powering accessories when you’re idling or parked.
I'm sure @Mycroft can make a model of an i4 with a 100m2 solar roof that would provide about the 20kW that are required to fully power the car running at 60mph (20kWh for 100km during 1 hour). It's only 10mx10m, so a bit more than twice the length and 5 times the width of the car. You might actually take off when going from 0 to 60mph in 3.9 seconds though. :ROFLMAO:
 

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Discussion Starter · #45 ·
Imagining driving down the highway and the intelligent assistant suddenly starts calling out “v1” , “rotate”, “pull up”, “terrain” with some confused driver not realizing what is about to happen.
 

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Imagining driving down the highway and the intelligent assistant suddenly starts calling out “v1” , “rotate”, “pull up”, “terrain” with some confused driver not realizing what is about to happen.
Haha, at "v1" I guess they'd have to realize that they're committed to keep on accelerating :)
 

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Discussion Starter · #47 ·
So back on topic.. as much as I think the i4 is a very good car.. i have agreed to purchase a 911 997 4S 😳 hopefully picking it up on Wednesday. But haven’t I agreed to buy an i4? Yes I have.. don’t know what I’m gonna do about that juust yet.
 

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Batteries down-cycling is starting... so after 10+ years in cars, battery capacity drops to 80% of original, but they are still good for another 10 years in mass storage facilities including charging hubs before they truly need to be recycled - its a start...
 

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Starting to have my doubts too...
One of these days, when I go back to the office (homeworking now all the time), I will consult our fleet manager to see what my options are.
 

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Starting to have my doubts too...
One of these days, when I go back to the office (homeworking now all the time), I will consult our fleet manager to see what my options are.
The way I see it, I'm happy with my ICE car now, and the only BEV I would consider buying is the i4 until something else comes along like an Audi A4/A6 e-tron (the Taycan/Audi e-tron GT is too expensive for me), so I may as well keep my order in, if something else better comes along before my order test in production I'll just cancel it. Proper BEV sports sedans is still in its infancy. And the i4 M50 is a great value all things considered, if I ever get it!
 

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Discussion Starter · #51 ·
I did buy that 911, and it’s fantastic. But I still want the i4, it really is a great car that I am genuinely excited about. The only other EVs are the Audi and Porsche ones, and they are so expensive they cost approx the same as both the i4 and the 911. So maybe I can do some mental gymnastics to justify having both.
 

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There is nothing in production that comes close to the i4 in terms of meeting my requirements or the amount I am prepared to spend on a car. Even if something better was announced today, and how likely is that, bearing in mind car manufacturers seem to like to pre-announce cars well in advance, I still won't get it outside my house until well after my order for an i4 arrives, even if it is the end of the year.

You can get an interim car, sell it when you get your i4, and take any hit on the loss, Or you can opt for a different car completely and potentially regret not waiting every time you get in the driving seat.

Psychologists see one of the key transitions from childhood to adulthood as the ability to delay gratification. However, we move more and more to a society where we are encouraged to think like children and expect everything now! It is also a comment on the quality of our lives that one of the most important things in it is a car! Maybe we should spend the time while we wait for our new toy focussing on how to improve the quality of our lives :unsure:
 

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Talking about delayed gratification, the link below gives a glimpse at what to expect for the next few years. Interesting that BMW's has a more balanced approach between SUVs and cars (2021: iX3; 2022: iX, i4, iX1; 2023: i3 (saloon), i5, i7), whereas Audi, disappointingly, seems to be sitting on the GT and focus on SUVs for 2 years (2020: e-tron; 2021: GT; 2022: Q4 e-tron, 2023: Q6 e-tron, 2024: A6 e-tron). Mercedes also released a bunch of SUVs before coming back to cars (2021: EQA, EQB, EQC, EQS; 2022: EQV, EQE). Year of launch a bit approximate for the late 2021/2022 launches.
 

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Talking about delayed gratification, the link below gives a glimpse at what to expect for the next few years. Interesting that BMW's has a more balanced approach between SUVs and cars (2021: iX3; 2022: iX, i4, iX1; 2023: i3 (saloon), i5, i7), whereas Audi, disappointingly, seems to be sitting on the GT and focus on SUVs for 2 years (2020: e-tron; 2021: GT; 2022: Q4 e-tron, 2023: Q6 e-tron, 2024: A6 e-tron). Mercedes also released a bunch of SUVs before coming back to cars (2021: EQA, EQB, EQC, EQS; 2022: EQV, EQE). Year of launch a bit approximate for the late 2021/2022 launches.
Most people these days want a crossover or SUV. Easier to get in and out of. Better sightlines on the road. With an EV, the low center of gravity from a big battery makes the cost of a tall roof and tall seating position less of an issue.

That said, a sedan just plain has more performance potential, and crossovers rarely look good. That's why so many of the newest are modeled after the I-Pace. Ian Callum is the master.

My main issue with the i4 is the lack of physical buttons. It's just retarded.
 

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Most people these days want a crossover or SUV. Easier to get in and out of. Better sightlines on the road. With an EV, the low center of gravity from a big battery makes the cost of a tall roof and tall seating position less of an issue.

That said, a sedan just plain has more performance potential, and crossovers rarely look good. That's why so many of the newest are modeled after the I-Pace. Ian Callum is the master.

My main issue with the i4 is the lack of physical buttons. It's just retarded.
I just want to register my very subjective view that none of the current SUV or Crossover designs, including the i-Pace, will ever be a Sports Sedan. The mere fact you are sitting higher changes how the car subjectively handles, never mind the physical constraints on the compromise between controlling the roll vs the ride. I do agree that the lowering of the center of gravity based on the batteries reduce the actual risk of roll-over.
 

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Discussion Starter · #57 ·
My neighbor has an i-pace and while I don’t think it’s bad, it came and went very fast in Norway and it’s certainly not very sedan like (for our market). The air suspension is pretty nice! He already sold it and also wants an i4.
 
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