Does It Make Any Sense That The Tesla ‘Cybercab’ Only Seats Two? Let’s Talk About It

Last night Tesla showed off a number of future products, including the autonomous two-door, two-passenger “Cybercab.” The company promises to sell the car for $30,000, offering owners a chance to be driven around in a steering wheel-less car with two Lamborghini-style doors and camera-based AV software that promises to drop you off at your destination. There are a number of elements about the Cybercab that any self-respecting journalist should be skeptical about, but right now I want to focus on one thing: How does a two-passenger cab make any sense? Well, it just might.

Here’s a bit from our Cybercab-reveal article:

Tesla headlines the Cybercab as “faster” and “more affordable.” Why? Well, you won’t be paying a human driver to sit in the seat to haul you around. Beyond that, it notes that the design relies solely on cameras for its self-driving ability. Tesla has long eschewed the use of more expensive radar or LIDAR sensors in its autonomous driving program.

Tesla also states you’ll be able to “call it once” and keep the vehicle “as long as needed,” whether you’re taking short trips or using it all day. Contrast that to a contemporary rideshare or taxi, which is only yours for as long as your trip lasts.

And here are a few photos:

The first thing some might say in reply to my headline is: “Well, most of the time a New York taxi cab is only transporting one or two people, anyway; three-wide is tight, and nobody wants to sit up front.” OK, sure. I buy that the average taxi ride probably involves shuttling only one or two folks around. But here’s the thing: I’m not sure I fully understand the benefit of a two-passenger taxi has over a five-passenger. But let’s talk about it.

Let’s have a look at some other taxi cabs from around the world, starting with two of what one could argue are the ultimate. The first is called the Toyota JPN Taxi, and, after riding in one in Hong Kong, I wrote a deep-drive on it earlier this year comparing it to its contemporaries. This is a phenomenal taxi cab layout:

Just look at how perfect the packaging is on this machine. There’s a short hood to house the entire engine/drivetrain, but everything aft of the cowl is passenger space. The rocker panels are low, allowing for easy ingress/egress, and that low floor, combined with a tall roof and an overall boxy shape, maximizes interior volume.

One one side there’s a sliding rear door for when you’re in tight spots, and on the other side there’s a conventional door. There’s tons of interior seating space, with the floor being perfectly flat thanks to a front-drive design:

And look at all the space for cargo:

Have a look at the side profile one more time:

Let’s compare that to one of the other benchmarks in taxicab design, the London Black Taxi, which Matt Hardigree drove, as mentioned in his article “I Drove A London’s Black Taxi And Discovered Why They Are Some Of The Best Purpose-Built Vehicles On Earth.”

The London Electric Vehicle Company (LEVC) “TX” has a seating configuration that’s arguably even more impressive than the Toyota JPN’s. Up front, partitioned off from the rear, is just the driver’s seat; the passenger’s door offers access to a nice flat luggage space:

And then there are not three, but six seats in the back!:

You’ll notice that the overall shapes of the London Black Taxi and the Toyota JPN are similar, and that’s because this footprint maximizes the ratio of interior volume to footprint — a key metric in cities that are already jam-packed with cars. Whats more, both designs offer excellent wheelchair access.

Especially relative to the best taxi cabs out there, it seems to me that the Tesla Cybercab design really doesn’t make any sense. Here’s what transporting five people would look like using Cybercabs:

Here’s what it’d look like using a London cab:

That doesn’t seem to make sense, but let’s talk about it some more.

Even if you look at the Cybercab as a private car and not an actual taxi, it’s definitely cool looking, and if it can drive itself, that’s amazing. But the market for two-passenger vehicles is so small. Typically two-passenger cars are sports cars, and you know what people typically enjoy doing to sports cars? Driving them.

So this isn’t going to take the place of a sports car, it’s not going to work as a family car, and as a taxi cab it would probably work for most taxi rides, but does it offer a significant benefit over a four-door taxi cab with a similar footprint? I mean, maybe it’s lighter and more aerodynamic, but how much of a consumption delta is there really between this and, say, a car shaped like a five-passenger Prius? And is that Vehicle Demand Energy delta associated with this sleek shape going to outweigh the fact that you now need multiple of these to transport groups of three or more?

I’m honestly curious about this. It’s likely that most taxi rides limit their efficiency by some amount by offering too much space when only one or two people are usually being transported. Why carry around extra weight and cost when you usually don’t have to? But most of an electric vehicle’s weight and cost is in its batteries, so upon first glance, I’m really not seeing how a five-passenger design isn’t the better call, here. If this were a tandem car, then I get it — two seats reduce the frontal area (though aerodynamics really only dominates at higher speeds, and I’d guess most taxis drive an average of 30 mph or so). But this? I’m curious if Tesla had some data to back up why this makes sense:

It doesn’t even look that small (in part, because a somewhat-long wheelbase is going to be needed for batteries). And if it’s a two-seater just to save money, surely scissor doors aren’t the move, right?

I’m always careful not to just knee-jerk react to Elon Musk creations, because that happens far too often in media. But I do have to call out when I don’t understand something, and I’m a bit confused here. Surely Elon Musk — a man who is all about optimization — has date to prove that this is optimal, right?

Then again, the Cybertruck is far from an “optimal” truck design, but it’s actually useful, and it fits into a category of vehicle for which there is lots of demand. But the Cybercab? It seems both suboptimal as a taxi and limited in its appeal as a private vehicle.

Or don’t. Maybe there’s no point in talking about the overall design when the whole thing relies on a car being able to drive itself — something that isn’t possible yet for the vast majority of the country.

Update: I called fellow engineer Huibert Mees just now to chat about this. He buys that a two-door design could offer significant cost and weight advantages, and if most cab rides are just shuttling around one or two people, that could mean it’s theoretically a better tool for the job the majority of the time. But it’s not clear whether the cost and weight and whatever incremental aero benefits (and again, aero really only dominates at highway speeds) outweigh the practical detriment of not being able to carry more than two people. 

What’s more, the technically correct answer isn’t always the actually correct answer, as human beings are irrational. Maybe most people commute to work by themselves, but they still want to have room for four in case friends or grandchildren or whoever come over. Ditto with cab companies, who might rather have a single car that can do more.Then there are people who have larger families, and on and on — you can see how a two-passenger car might have limited appeal.

The result is that a two-passenger vehicle could theoretically end up being more expensive than a four-door simply because its volume limits is ability to reduce cost to the same degree. It could fall short in economies of scale. So at that point, you’ve got a car that’s more expensive, maybe negligibly slipperier through the air, and definitely lighter, but perhaps not to the point where it matters that much. 

Again, this is all just theory, and again, you’d hope that someone ran the calculations. They basically calculated the efficiency gain of going with a two-door versus a four-door, considered what percentage of cab rides involve more than two people, and ultimately determined that it’s more efficient to go with the lighter two-door design and to occasionally send two cars for parties of more than two. 

Oh, and it’s worth noting: That comparison to current taxi cabs above only makes a little bit of sense, because naturally a two-passenger human-piloted vehicle isn’t going to suffice unless there’s just one client, and they’d have to sit up front next to all the equipment. A two-door cab makes way more sense on a self-driving car than on a human-driven one, even if it’s not 100% clear that it makes the most amount of sense over, say, a similarly-short four-door. I’d love to see the data on all this.