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by semi-extrinsic 3063 days ago
> If Tesla made a van, I would have strongly considered it

I'm certain the reason they don't is that it would either have a sub-100 mile range (like the actually existing Nissan NV200e electric van), or it would have a 10 000 lbs curb weight and cost well north of $200k.

I mean, at highway speeds air resistance is what you're spending your gas/electricity on fighting against.

For a Model S, measured drag coefficient and projected frontal area imply that to maintain 70 mph for one hour you're spending 10 kWh.

For a Ford Transit van, the drag coefficient doubles and the projected area increases by a whopping 5x, so you're looking at 100 kWh spent to maintain 70 mph for one hour.

This implies an electric full-size van with the range of a Model S would require at least 600 kWh of battery capacity installed, giving a battery weight alone of 7500 lbs (3500 kg)!!!

2 comments

I think the answer is simpler than that; minivans aren't sexy. Tesla is focused on gobbling up potential BMW and Audi buyers who have the budget for a fully loaded X5 or Q7 and aren't willing to give up the sex appeal (at least until kids 2-3 come along).

A Ford Transit van is a pretty big leap for someone who wants a vehicle to cart around kids, pets and their associated gear.

The 2017 Chrysler Pacifica offers a drag coefficient of 0.30 vs. 0.24 for the Model X. Given Tesla's aggressive reduction in drag and frontal area on the Model X (with respect to other SUVs) I expect they could get away with a much more modest bump in battery capacity if minivans became the next hot ticket.

You're right that minivans aren't sexy. And that the Model X has significantly better aerodynamics than a X5 or a Q7. But it doesn't match the carrying capacity of either.

I mean, with a Q7 you can carry your three kids with just two seat rows, so you can still fit two strollers and enough luggage for a three week holiday in the trunk. With a Model X, not so much. And thanks to the fancy doors, forget about compensating with a roofbox.

It's more comparable to a BMW X4 or a Mercedes GLC Coupe. And even then, the Model X is almost 90 inches wide, same as a H1 Hummer, as opposed to 77 inches for the "bigger" Q7.

From an engineering standpoint it seems like it is just a weight and packaging problem to me.

The Pacifica PHEV weighs about 5,000lbs depending on configuration. I think the only deficit it really has to the Model X is drag co-efficient but Chrysler was working with a given shape. Given a unique platform not shared with a gas variant they could design for a specific co-efficient as needed.

I don't really know the specs of the Model X, however Google says it weighs maybe 300lbs more than the Pacifica. Those aren't unsurmountable differences - especially if the price range is going to be 80k+.

I think the biggest difference is that Tesla knows it won't sell enough vans to make it worth their development time :)

> I think the only deficit it really has to the Model X is drag co-efficient

No, the projected area is also worse. Air resistance is proportional to drag coefficient multiplied by projected area. Since both are worse, the best estimates I could find is that the Pacifica has almost twice the overall air resistance of a Model X.

It's not as bad as the 6x difference between a Model S and a Ford Transit, but it would still mean almost half the range at a given battery capacity.

Conversely, an electric Pacifica with the range of a Model X would be about 1000 lbs heavier.