ajdelange

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I guess I should have added that "rated range" is what is displayed next to the battery icon if you select "miles" for the battery charge display. Otherwise it displays SoC in %. Much more useful IMO.

The estimated or projected range based on instantaneous or average consumption is displayed in a box on the Energy graph on the main display screen.

Rated range depends on driving conditions only through their effect on the battery SoC. If you drive x miles uphill fast you will deplete more battery than if you drive those x miles gently on level ground and the displayed miles will go down faster. Estimated range, conversely, depends on the rate at which you are consuming power. If you set averaging for miles and drive down hill the whole way you won't use any energy and the estimated range will be infinite (represented as 999).
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I need to make a correction - in using the Model X as a surrogate for the CT I forgot to factor in the efficiency penalty that the CT would have over the Model X due to the difference in cd values. The Model X has a cd of .24 and the CT should have a cd of .30 (per Elon’s tweet). I don’t have a source, but as best as I can glean from different examples (see link) this would equate to about a 15% penalty in efficiency. (This would not be the percentage difference between the two values but the measured effect.) So with a 200 kWh battery, all other things being the same, the range would be calculated as 495 miles (200 kWh / 404 Wh per mile) and with the 16% efficiency gain from the 4680 cells the calculated range would end up at 575 miles.

https://aia.springeropen.com/articles/10.1186/s42774-020-00054-7/tables/2
 
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CompMaster

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I'm curious if Tesla will do what Ford did. Range is estimated with with a 1 thousand pound payload. If so the 500+ should definitely easily got beyond 610+ when not loaded.

 

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625 miles is 1000 km by my math of 1 mile = 1.6 km
Yes, but you are forgetting to factor in the "bottom end" reserve that will programmed into the range calc to keep you from discharging to zero!!!!!!!

Make that 15 miles and we're golden!:cool::ROFLMAO:
 

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I'm curious if Tesla will do what Ford did. Range is estimated with with a 1 thousand pound payload. If so the 500+ should definitely easily got beyond 610+ when not loaded.

I finally watched the MKBHD video and realized Ford did figure it out (reference to other thread) but not in the way that anyone has said explicitly.

How much power does the F-150 lightning have? Enough to power a house. The beauty of this is that very few will actually question it. The ICE crowd isn't interested in pack size or efficiency. Make me feel like I can give up my dinosaur juice. (Insert V2G, add asterisks to the bottom of everything) and voila there's a story anyone can tell.

Someone in Ford marketing deserves a cookie for threading the needle.
 

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I'm curious if Tesla will do what Ford did. Range is estimated with with a 1 thousand pound payload. If so the 500+ should definitely easily got beyond 610+ when not loaded.

Two things

1. At non-stop highway speeds, once you have accelerated to a steady speed carrying 1,000 lb of payload makes very little difference. At highway speed the overwhelming amount of energy usage is from aerodynamic drag and this aerodynamic drag increases even faster with each little bit of extra speed you drive at.

2. Do you have a link to any document, tweet or video by Ford that the estimate included 1,000 lb payload?
 

Crissa

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They said the 1000 pounds thing in front of a few reporters/influencers. But Ford didn't write it down anywhere.

-Crissa
 

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Well argued first post.

I'm generally wondering what the Wh/km use is for all three CT drivetrains and how they compare. Hopefully we'll get some more details soon on the production CT.

In regards to effective on-road range though at some point a "single charge non-stop range" becomes mute if you need to stop a few times for health reasons anyway (stretch, bathroom, food etc) at which time you can also plan a fast charge and not add any overall travel time to the journey.

Given most CT customers don't have the need for excessive single charge range, and if so only rarely within the lifetime of the vehicle, the question then becomes what the positives or negatives of having more range onboard are and so what is the maximum useful and economic single charge non-stop range a vehicle should have. To get a better understanding I think it can be broken into three consumption profiles: sealed road, un-sealed remote roads and overlanding/offroading.

Typically sealed road use also implies some sort of civilization along the route where charging options might be reduced, but at least still available. My logic is that sealed roads are mostly made to support traffic, and traffic flows between locations with populations, which in turn generally have power available for charging. For example what is the longest direct route to the nearest fast charging option available using a sealed road in the US? 300-500miles (Alaska?)? I'd say here in Australia, especially atm, that can be up to 1500miles with WA having the loneliest Supercharger in the world atm (1 in the whole state which is 4x size of Texas at 2.5million sqkm). If we include destination chargers though, on-road you could be back down to 300-500miles as well in Australia. Typical cases will be in the 100-200mile range.

That leads to the next point which is how far is it comfortable to travel each day, we need to sleep too. Sleep time also makes destination chargers feasible. I'd say a 600mile battery would cover 99% of useful day to day trips for 99% of CT users. Anymore and it's likely that the added battery weight is actually become a negative for the vehicle in increased tyre and drivetrain wear, energy use and even secondary things like road wear etc. (Believe it or not tyre rubber particle emissions is also a negative environmental thing).

Accordingly I'd assume that the upper useful range limit for an EV, with decent access to superchargers would be more in the 300mile (500km) range, with more "outback" locations in the 500mile (800km) range. In particular in remote areas a return trip to a charger actually will become more common, meaning effective one-way range is halved. But we're talking edge cases in remote outback areas, so I'm guessing maybe 5% of customers that would apply to, and then only infrequently? It would be inefficient for any manufacturer to accommodate them in a vehicle design.

And then that leaves us with the third area where range can become critical. Overlanding and off-roading. Here trips are complicated because charging sources are even less, and off road use (especially in sand) can be especially high (up to 3-4x as high than onroad). If you have 600mile on-road range, you could easily be looking at 200mile of sand driving range. That's only 100miles in and a 100miles back out to a charger. The only real way to overcome this is decent tyre choice which in turn reduce onroad consumption. Unlike onroad where halving your speed can more than double your range in EV, off road vehicle speeds are not as significantly impacted by aerodynamic drag. Off road is still a bit hard for an EV IMHO.

Given the above, I'm pretty confident even in outback Western Australia a 500mile range CT will get me by in 99% of use cases, 600mile range would be just icing on the cake and maybe make it 99.5% :)
 

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Yes, but you are forgetting to factor in the "bottom end" reserve that will programmed into the range calc to keep you from discharging to zero!!!!!!!

Make that 15 miles and we're golden!:cool::ROFLMAO:
As you know, I'm simply converting the actual distance based on math.... not the distance a car can go.
 

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A 600-mile battery pack would weigh... well, rather alot. More than the one in the Model S P100 did.

-Crissa
 

ajdelange

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I need to make a correction - in using the Model X as a surrogate for the CT I forgot to factor in the efficiency penalty that the CT would have over the Model X due to the difference in cd values. The Model X has a cd of .24 and the CT should have a cd of .30 (per Elon’s tweet). I don’t have a source, but as best as I can glean from different examples this would equate to about a 15% penalty in efficiency.
Drag is proportional to drag coefficient so the penalty for these numbers is 0.30/0.24 = 5/4 = 1.25 i.e 25%. Now that's per unit of frontal area. I think the CT is going to have greater frontal area than the X. If it is say, 20%, the drag penalty would be (5/4)*(1.2) = 1.3 or 30%. The drag component of consumption (Wh/mi) will increase by this amount. As drag is going to be larger relative to rolling resistance, slip and drive losses and as it goes as the square of velocity it will emerge as dominant at lower speed and the penalty for driving fast will be higher.



So with a 200 kWh battery, all other things being the same, the range would be calculated as 495 miles (200 kWh / 404 Wh per mile) and with the 16% efficiency gain from the 4680 cells the calculated range would end up at 575 miles.
If you assume that you pick up 16% increase in efficiency from the batteries but lose 30% to drag it's clear that you will not pick up any range at all. Now drag is not the only force here so that you would not be losing 30 - 16 = 14% at lower speeds. I think we can give the Tesla engineers credit for understanding these things better than we do. The TriMotor will have an EPA range of 500 miles (or a little over - they need to beat Lucid) and will deliver on road performance commensurate with that. Becuse of the higher drag coefficient and frontal are the speed penalty will be more dramatic than it is with the X.
 

ajdelange

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I'm generally wondering what the Wh/km use is for all three CT drivetrains and how they compare. Hopefully we'll get some more details soon on the production CT.
Everyone is wondering that but in North America we are wondering in Wh/mi. About the best we can do at this point is make an assumption that the battery is unlikely to be more than 200 kWh and using the proclaimed TriMotor range of 500 miles calculate that consumption is going to be around 400 Wh/mi (247 Wh/km). Most people seem to be comfortable with that number though ABRP uses 490 (or something close to that). This would imply 245 kWh of battery. That seems a lot. Going the other way a 180 kWh battery would imply 360 Wh/mi. So it's likely going to be 400 ± Wh/mi.

There will be some variation between the models but as has been pointed out weight has a minor effect. The TriMotor battery will be heavier increasing Wh/mi a bit but the larger battery will exhibit less loss and 3 motors will be more efficient than 1 or 2 offsetting this though doubtless not exactly.
 

ajdelange

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1. At non-stop highway speeds, once you have accelerated to a steady speed carrying 1,000 lb of payload makes very little difference. At highway speed the overwhelming amount of energy usage is from aerodynamic drag and this aerodynamic drag increases even faster with each little bit of extra speed you drive at.
Much of limited access road driving these days involves speeding up and slowing down often, alas, to the point of having to come to a complete stop or crawl. In such cases intertial load is, if briefly, the biggest load. Also in hilly terrain you have to put potential (gravitional) energy into the load. That can be appreciable. But we have regen! Much of the inertial and potential energy we invest is returned to us if we can keep our feet off the friction brake pedal. Regen isn't 100% efficient so more weight does impose a penalty but it is a small one.

Now if you take your anvil collection up to your mountain cabin it's going to cost you kWh but, provided you take it home with you when you leave you will get most of that back. There is somewhere a quarry located at elevation. Their product (rocks) get hauled to a processing plant at lower elevation. The trucks are electric. They are never charged.
 

JBee

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There will be some variation between the models but as has been pointed out weight has a minor effect. The TriMotor battery will be heavier increasing Wh/mi a bit but the larger battery will exhibit less loss and 3 motors will be more efficient than 1 or 2 offsetting this though doubtless not exactly.
Thanks for the info on wh/mile. :)

When I was doing some numbers before they mentioned the Cd in 2019, I came up with 375Wh/mile from my fluid dynamics modelling. It will depend how well they can get that flat front grill to separate airflow around the body (it creates a vortex that makes the front appear round) and then get the air to stay laminar around the side windows and across the rear wings. The wheel wells and flares are another issue, but lowering the car helps a fair bit, making the air suspension essential to meet the range forecasts.

Why do you think that a trimotor will be more efficient that a dual? I was under the impression that like in the M3 they'd use a combination of PM motor in the front for cruising on-road (because it's more efficient) and induction in the back for extra traction and performance?
 
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