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10 things we learned about tunnels and Tesla from Elon Musk's TED interview

10 things we learned about tunnels and Tesla from Elon Musk's TED interview


Including why Musk wants to beat Gary the Snail

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Elon Musk is the head of a spaceflight company, an electric car manufacturer / solar energy effort, and a brain-computer interface project. Recently, though, he added a tunnel boring company to that already crowded plate. This past weekend he spoke about The Boring Company, as he’s calling it, for the first time in public with Chris Anderson, the curator for TED Talks.

It wasn’t a hard-hitting interview — while Anderson got Musk to share some details about the tunneling project, he also teed up many of the billionaire CEO’s favorite talking points, and his followups were often “whoa” or “wow.” You can watch the full video above, but here are our 10 biggest takeaways from the conversation.

Musk wants the tunnels to span the country on a deep level

Musk said that there’s “no real limit” to the depth of his proposed tunnels. “The deepest mines are much deeper than the tallest buildings are tall, so you can alleviate any arbitrary level of open congestion with a 3D tunnel network.” This, Musk said, is how to get around the most popular rebuttal so far: that underground tunnels will simply spread the congestion to a new place without completely solving the problem of traffic. Musk thinks it will be possible to create “any arbitrary number of tunnels, any number of levels” in order to reduce congestion on the surface.

There needs to be a massive cost reduction before a tunnel network gets built

Anderson mentioned that this project sounds expensive, and Musk agreed. “We need to have at least a 10-fold improvement in the cost per mile of tunneling,” Musk said. He thinks there are two things that will allow The Boring Company to achieve that kind of cost reduction.

One is to cut the typical diameter of a tunnel “by a factor of two or more” to 12 feet. “A single-lane tunnel would have to be 26 or 28 feet in diameter to allow for emergency vehicles and ventilation for combustion engine cars,” Musk said.

A CGI rendering of the The Boring Company’s concept, where cars would avoid traffic by being pulled underground on “electric skates.”
A CGI rendering of the The Boring Company’s concept, where cars would avoid traffic by being pulled underground on “electric skates.”

“But if you shrink that diameter to what we’re attempting, which is 12 feet, which is plenty to get an electric skate [this is what Musk is calling the contraptions that will grab the cars from the surface and move them through the tunnels] through, you drop the diameter by a factor of two and the cross-sectional area by a factor of four. And the tunneling cost scales with the cross sectional area, so that’s roughly a half order of magnitude right there.”

Next, Musk said that he wants to make his boring machines carve out tunnels and reinforce the walls being created at the same time. (Those are currently separate steps.) Musk thinks this could double the efficiency of the process which, combined with smaller tunnels, gets him to a place where he can reduce the cost by a factor of eight.

Musk then amended his short list by adding one more goal. Current tunneling machines don’t operate near their thermal or power limits, and he believes he can beat that. “If you can jack up the power to the machine substantially, I think you can get at least a factor of two, maybe a factor of four or five improvement on top of that,” he said.

The goal for The Boring Company is to beat Gary the Snail from SpongeBob SquarePants

Musk said current tunnel technology literally doesn’t even operate at a snail’s pace. So he’s put a target on the back of the most well-known snail in pop culture: Gary the Snail from SpongeBob SquarePants. “Currently he’s capable of going 14 times faster than a tunnel boring machine,” Musk said. “We want to beat Gary. He’s not a patient little fellow. That will be victory. Victory is beating the snail.”

“Victory is beating the snail.”

Hyperloop technology could be used in underground tunnels

Since Musk is now associated with two different kinds of tunnel technologies — one being the underground transportation system, the other being the above-ground hyperloop — Anderson asked him to reconcile the two. Musk said that some hyperloop tech could be used underground since the tunnels are already designed to withstand five or six atmospheres — far more than what’s needed to create the vacuum required for hyperloops to work. Musk believes underground hyperloops would be ideal for certain routes, like Washington, DC to New York City. “There’s no real length limit,” he said.

Musk isn’t leaving Tesla anytime soon

The Boring Company is only taking up “maybe 2 to 3 percent” of Musk’s time. “This is basically interns and people doing it part time,” he said. Anderson then asked if Tesla has done enough for the electric vehicle market to make Musk comfortable with moving on. Musk said he sees himself staying with the company “as far into the future as I can imagine,” because “there are a lot of exciting things that we have coming” including the Model 3 and the Tesla semi truck.

He still has aggressive timelines for Tesla’s self-driving tech

Musk is known for playing fast and loose with the timelines for his grandest ideas. In the interview, he said Tesla is “still on track for being able to go cross country from LA to NY by the end of the year, fully autonomous” with one of its cars, “from a parking lot in California to a parking lot in New York, no controls touched at any point during that journey.”

From a parking lot in California to a parking lot in New York without touching any controls

He also thinks Tesla’s tech is about two years away from allowing a driver to sleep through entire rides. “The real trick of it is not ‘how do you make it work 99.9 percent of the time,’ because if a car crashes say one in a thousand times then you’re probably still not going to be comfortable falling asleep,” Musk said. Instead, he thinks the chance of a crash would have to shrink to one in 100 or 1,000 lifetimes in order for people to be comfortable enough with autonomous technology that they’d be willing to nap in a self-driving car.

Musk says shared autonomous cars are “100 percent what will occur”

A future full of self-driving cars might change how we think about ownership. Musk doesn’t think owning a car will be completely out of the picture, but he believes sharing will play a big role.

“Absolutely this is what will happen: so there will be a shared autonomy fleet where you buy your car, and you can an choose to use that car exclusively, you could choose have it be used only by friends and family, only by other drivers who are rated five stars, you can choose to share it some times but not other times. That’s 100 percent what will occur, it’s just a question of when.” 

Musk has driven a prototype of the Tesla semi, and it’s apparently really fun

The Tesla big rig will be unveiled later this year, so it’s no surprise to hear that the company’s got a working version that, apparently, Elon’s already driven. “When I was driving the test prototype for the first truck, it’s really weird, because you’re driving around, and you’re so nimble, and you’re in this giant truck,” Musk said. “I drove it around the parking lot. I was like ‘This is crazy.’ Driving this giant truck and sort of making these mad maneuvers.”

Citing the impressive torque associated with electric motors, Musk said the forthcoming Tesla semi truck can “out-torque” any diesel truck. “If you had a tug of war competition, the Tesla semi will tug the diesel semi uphill.”

Tesla will announce its new Gigafactories this year

Musk thinks that about 100 of his battery-producing Gigafactories might be enough to help shift the world toward completely sustainable energy, and in working toward that goal, he firmed up plans to announce “somewhere between 2 and 4 Gigafactories later this year. Probably 4.” He didn’t say where they’ll be, only that “we need to address a global market.”

Musk played down his connections to Trump

Anderson didn’t push Musk hard on his association with Donald Trump, but he did (kind of) ask Musk to address the criticisms of that relationship. Here’s Musk’s full answer:

First of all I’m just on two advisory councils where the format consists of going around the room and asking people’s opinion on things. So there’s like a meeting every month or two. You know, that’s the sum total of my contribution. But I think to the degree that there are people in the room who are arguing in favor of doing something about climate change or you know other certain social issues — you know, I mean, I’ve used the meetings I’ve had thus far to argue in favor of immigration and in favor of climate change. And if I hadn’t done that, there wouldn’t — that wasn’t on the agenda before. So maybe nothing will happen, but at least the words were said.