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Next-Gen Tesla Roadster Electric Range To Be Outrageous

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TMC Staff

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May 19, 2017
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There’s a magical number that Musk says will be surpassed. The upcoming, all-new Tesla Roadster will have the highest electric range of any production EV ever made. In fact, it’s electric range will exceed 1,000, but not in miles. With the recent range upgrades for the Tesla Model S and Model X, the question of...
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Roadster is all about crazy range and acceleration.
To make it really go to 4000 kph crazy quickly, of those 3 motors probably none can be anything other than a big fat induction unit such as seen in Model S/X, probably even the extra bulky and lossy Performance version.
To stick one PMSR motor in there, such as the S and X now receive, acceleration will be someone restricted at higher speeds as the slip limit for 211 kW is not all that fast, even on the front wheels.
It's a trade-off, though. More efficient motors will save good weight while still achieving targeted range.
In Model S/X, the motors and new inverter probably added around 6% in range for the non-P versions such as could have been the lone front motor, the other 2% coming from min/max voltage changes, bearings, HV cabling, etc. Let'say 1000km is the target and they never considered to PMSR motors, but now WOULD, then in stead of the previously necessary 200 kW with all-Performance motors, they could suffice with 188 kW. 12 kWh in cells weighs 48 kg and then there are some connectors and fuses. Say, 60 kg to be saved. On top of the ~20 kg in the motor itself, so 80 kg. That 80 kg is ~4% of the car. Losing (round number, no clue what it might be) 50 kW or so by taking a lighter front motor would drop peak power from 1,000 kW to 950 kW, some 5%. So it actually might all work out.
But then, we have to be real here. When tesla came out with the number, which is after they put the first Roadster prototypes together, they really knew all about the tech that's not being implemented in S/X.

200 kWh to achieve 1,000 km EPA never was really impressive for a smaller car. Old Roadster was way more efficient than Model S, but New Roadster would be way lossy. This would be partially explained by the 4x bigger battery adding weight and then completely by having only super lossy Performance induction units to choose from.

But say they make a slightly slower version, 3x that PMSR motor with some clever clutches to allow some to be turned off. Smaller battery, say 120 kWh. That all would save good weight, 400-500kg or so. 633 kW in a lighter car, that is going to be bonkers still. I can see around 2 seconds to 60 mph still be possible. Heck, even 400 kph max is still possible with that sort of power although there may not be a gearing that allows for both the top speed and the low speed torque needed.
A car lighter and lower than a Model 3, using the same motor but in the front, should achieve a lower consumption figure. In stead of 150 Wh/km, let's go for 140 Wh/km which is quite conservative. With 112 kWh usable, that would make for 800 km of range on the EPA cycle. Not too shabby, huh?
Tester report that even the 3PD lack a bit of the punch of an SP100DL and that that's due to the motor being a different technology. But if you roughly double that power and reduce the weight, I'm sure all will be fine :-D

Now putting that 800km 120 kWh Light Roadster on the track...
We know these PMSR motors are quite able to deal with continued pushing, much better than the motors in P100DL cars.
With a car lighter than the 3PD, having double the power to the road and even less heating issues (better inverters), wider tires, track focused suspension, 400-500 kg lighter than the Big Roadster, it may well track (much) faster.
Now, Tesla is not in the business of making the best car they can. They focus on making cars the way they like them. All but completely ignoring knowledge and trends in the market. So I don't think they'll make a Roadster with 3 (let alone 4) of their cheapest most efficient motors. 4 motors is well established as the best way to get track performance, but they feel they've done enough showing a working prototype that felt really quick to those who got a 0-60 ride in it.
Tesla barely cares about on track performance. Proven by Randy Pobst's involvement actually delaying Track Mode. They were going to launch it as he got to test it and then it turned out to not be all that great. That's right, they were to roll out Track Mode without due diligence asking a pro driver. And then he got only a few hour with the engineers, on track. Then it was released to cars.

An ambitious hacker/mechanic may well be able to shed that 400-500kg off the Roadster they'll sell, and make it work efficiently without any Tesla assistance. Lap it faster than the original thing, while getting better economy and 800 km of range to boot. But Tesla won't care. I hope they prove me wrong and FOR ONCE go for a best effort. Not just a one trick pony that goes quick straight on while dumping a godawful amount of waste onto the environment to get a silly 3-figure range whatever the economy. But in stead of saving the world, they are more likely to actually try and stick cold thrusters into the back seat to make the (needlessly heavy) 200 kWh actually fly for a few seconds. And I do believe it could be done. But imagine they make the lighter version first and stuck the thrusters into that one. How that would play out for 3D thrust performance boost...
 
OK, I also had this same thought. . . 620 miles = approx 998 km. Therefore, saying it will exceed 1000 km range seems like a ridiculously weak statement. 1001 km range would be 622 miles. Big freakin deal. But the implication of the tweet is that it could beat that number by a substantial amount.

How substantial? Well, we now have a Model S with 100 KWh battery and 370 miles range. If the Roadster has a 200 KWh battery (as stated) and is equally efficient as the Model S, that would imply. . . 740 miles!

Matching the efficiency of the S is not a given; there are a lot of variables that can affect the efficiency. What this crude calculation does show, I think, is that exceeding the original 620 mile estimate by a significant amount (let's say, by 10% or more) is not a crazy thing to contemplate.
 
My MS gets 280 “usable” miles on a 100% charge which is 335 claimed by Tesla. If the Roadster gets north of 500 in real world use I will be totally thrilled with the car.

I’ve had dozens of cars and none of them (Porsche, Ferrari, MB, BMW, etc.) has made me happier than my two MS’s. If the Roadster is close to as promised I can’t imagine how awesome it will really be. I was happy to plunk down the deposit and haven’t regretted it once. Even the wait is good by me - it will be even sweeter after a long and painful wait!
 
My MS gets 280 “usable” miles on a 100% charge which is 335 claimed by Tesla. If the Roadster gets north of 500 in real world use I will be totally thrilled with the car.

I’ve had dozens of cars and none of them (Porsche, Ferrari, MB, BMW, etc.) has made me happier than my two MS’s. If the Roadster is close to as promised I can’t imagine how awesome it will really be. I was happy to plunk down the deposit and haven’t regretted it once. Even the wait is good by me - it will be even sweeter after a long and painful wait!
Are you in it for the tech experience or the greenliness? The Roadster with 200 kWh will be anything but green, of course. No emission while driving, but at production...
Can't you take a 15 minute charging break halfway through a day of driving for the benefit of Mother Earth, so your battery can be half in size? It would make the car more sporty to drive as well, that's a lot of weight.
 
No! Keep the big battery.
I drive a lot- it will ”pay itself off” re: greenliness
Would throw me a basic calc for that? Or is it just a trade-off between convenience and the environment, as for many ICEV drivers?

Those who drive new ICEV's for only a few years of course cause less pollution than those driving similar new BEV's, let alone big battery ones. Used car drivers pollute much less as they are effectively recycling and accepting a lower luxury factor. BEV wins big time of course in the used car space. Only emissions are brake and tyre dust. Both are a bigger concern to me than CO2. Older ICEV cars pollute other nastiness I don't need.
 
Cloxxki, you are right about used cars. And it is a trade-off. I charge from solar so the car will be very green from that point of view, your points about brakes and tyres are well-made.
I like the big battery for range (and crazy power), the extra weight is only a small contributor to range loss.
I keep my cars in good nick, so the Roadster 2020 will be a fab used car for someone down the line.
But no, I can't defend my statement with numbers. Only a qualitative feeling that the environmental costs of manufacture will be spread out over many years of many kms of solar-powered driving.
 
Some napkin calculations...

6 x 20 min. = 2 hours
(swag) 60mph...
2hr x 60mph = 120 miles

(swag) 10% buffer
(100-10)% * 200kWh = 180 kWh

180 kWh / 120 miles = 1500 Wh/mi.

Yah, I think a 6 session day with 20 min./session is viable for a Roadster if it's anywhere near a modern P100D in terms of efficiency and near a modern P3D in terms of temperature management.

I hope the brakes are up to the task though.
 
Would throw me a basic calc for that? Or is it just a trade-off between convenience and the environment, as for many ICEV drivers?

Those who drive new ICEV's for only a few years of course cause less pollution than those driving similar new BEV's, let alone big battery ones. Used car drivers pollute much less as they are effectively recycling and accepting a lower luxury factor. BEV wins big time of course in the used car space. Only emissions are brake and tyre dust. Both are a bigger concern to me than CO2. Older ICEV cars pollute other nastiness I don't need.

If you're concerned with cO2, get a bev and solar. Almost all emissions are from mfg only. Then, think how long that car will last if it's built out of aluminum... :)
 
If you're concerned with cO2, get a bev and solar. Almost all emissions are from mfg only. Then, think how long that car will last if it's built out of aluminum... :)
You are totally right. And with Roadster, there is so much CO2 emitted in production, it could as well have been running on motor oil. It's not going to get great mileage anyway. Lot of theoretical range, though.
Anyone pretending to have a green supercar will be called out by your truly. No such thing.

Many on this forums want it both ways. Zero emissions, happy butterflies anywhere and guilt free battery range.
I don't worry about CO2 at all. LIfe on Earth was better when CO2 was high. First temps rise, then CO2 does.
If someone worried about CO2 in a genuine way, they'd take the bus and replant deforrested areas.