It looks like SLATE has pathetic EV efficiency. (and a rant).

[Luxrage]

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The 1988 facelift of the Renault Espace was championed by the press at the time for reducing the drag to .32. Touches like the flush mount side windows and low profile door handles do for drag reduction.

Edit: As a benchmark for the slate, according to a hyper-miler website I was looking at, a 2001 ranger has a Cd of .49

 

[atebit]

mi/kwh is highly variable based on driving style, up/down elevation, weather, etc. Any “expected” quoted value would be at best highly subjective IMHO.

 

[Daemoch]

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Classic example:
0.42 !

 

[zipn]

mi/kwh is highly variable based on driving style, up/down elevation, weather, etc. Any “expected” quoted value would be at best highly subjective IMHO.

I disagree to the same extent the conventional MPG ratings on a vehicle sticker is variable. it all depends on the testing. If EVs had a standardized test routine that all followed similar to the EPA's MPG, then they could be equally compared.

What's more variable is the range and also charge time as any measure of efficiency. It relates to the electronics and the battery size, but not in any way a measure of the ability to go a few miles on a single kWh. Sadly, those are the metrics manufacturers love to shout about.

Until there's a standardized miles/kWh test routine, the best I think we can do it take the manufacturer's max advertised range / advertised battery size and see how it compares to other makes and modes using the same formula. The Slate's smaller battery is rated 52.7 kWh with an expected range of 150 miles. 150 miles / 52.7 ... That's the same as ~2.8 miles/kWh.

Using that simple equation, as I originally posted, I think the SLATE should o be better considering its smallish size and supposedly lighter weight with the smaller battery option . I acknowledge that trucks aren't the most aerodynamic designs, but EVs have been improving year over year yet the brand new SLATE falls on the crappy side of miles/kWh. SLATE should do better.

 

[Driven5]

If EVs had a standardized test routine that all followed similar to the EPA's MPG, then they could be equally compared.

The EPA already specifies the same standardized test routines for EV's as they do for ICE's, to produce the MPGe rating. The standardized test routines are also used to determine a rated range, for equal comparison. Slate simply has not made it to this point in the process yet.

 

[danielt1263]

Until there's a standardized miles/kWh test routine, the best I think we can do it take the manufacturer's max advertised range / advertised battery size and see how it compares to other makes and modes using the same formula. The Slate's smaller battery is rated 52.7 kWh with an expected range of 150 miles. 150 miles / 52.7 ... That's the same as ~2.8 miles/kWh.

But that's the very problem I pointed out... We don't know the "manufacturer's max advertised range" because slate has not said what that is.

They have posted that the usable range is 150 miles. If that assumes working the battery from 80% to 20%, then it would mean the max range is actually 250 miles (giving 4.7 miles/kWh). But maybe they are making some other assumption in order to determine "usable range" we just don't know.

 

[zipn]

But that's the very problem I pointed out... We don't know the "manufacturer's max advertised range" because slate has not said what that is.

They have posted that the usable range is 150 miles. If that assumes working the battery from 80% to 20%, then it would mean the max range is actually 250 miles (giving 4.7 miles/kWh). But maybe they are making some other assumption in order to determine "usable range" we just don't know.

I'm hoping Slate is under-estimating the range. Better to under-promise and over-deliver. Unfortunately we only have what they say to go on right now, and right now, I think it looks pretty inefficient for a small, lighter-weight EV. I don't see much of anything in their information on the design of the truck that addresses efficiency.

 

[AZFox]

I don't see much of anything in their information on the design of the truck that addresses efficiency.

(source)

FWIW, the DOE has a page that explains how vehicles are tested.

https://www.fueleconomy.gov/feg/how_tested.shtml

 

[zipn]

(source)

FWIW, the DOE has a page that explains how vehicles are tested.

https://www.fueleconomy.gov/feg/how_tested.shtml

That's the numbers, but no discussion about design and engineering to improve efficiency. For example, the side mirrors, the front facia, the choice of tire, etc.

 

[AZFox]

That's the numbers, but no discussion about design and engineering to improve efficiency. For example, the side mirrors, the front facia, the choice of tire, etc.

Maybe someday, but for now they should focus on getting the design completed, the plant built, and production started.

 

[sodamo]

To me the mileage question is rather minor, almost a distraction. My day to day driving will be well within the limits. The only reason to even question would be a very very attractive price for the extended battery, but just guessing, I‘m 99% in for the Standard at 150. Now if that got tweaked to say 175, wow.

 

[KevinRS]

That's the numbers, but no discussion about design and engineering to improve efficiency. For example, the side mirrors, the front facia, the choice of tire, etc.

They aren't going to open source, in real time the design and work they are doing on the truck. If they did that, a chinese company would copy it and beat them to market with an imitation.
You can see the flat door handles that are somewhat similar to those on Teslas to see that they are doing some aerodynamic work.

You can't compare mileage on an electric truck to an electric car.
The maverick hybrid gets at best 37 mpg, and that's the best you can get in a truck.
The prius hybrid gets up to 57.
The form factor makes a huge difference.

 

[danielt1263]

Unfortunately we only have what they say to go on right now...

And that's exactly my point. What they have said right now is 150 miles usable range. You said yourself that in order to do your calculation, you need the max range. I'm telling you, you don't know the max range because they haven't announced it.

 

[AZFox]

And that's exactly my point. What they have said right now is 150 miles usable range. You said yourself that in order to do your calculation, you need the max range. I'm telling you, you don't know the max range because they haven't announced it.

They've announced estimated Combined EPA Range.

The usable portion of the battery is the portion of the battery that hasn't been reserved (deliberately made unusable) in order to protect the battery's long-term health.

"Usable range" means maximum range the usable portion of the battery will allow you to travel.