By now, people are used to surprises from Elon Musk of Tesla Motors and Space X fame. A car, a rocket … and now something that’s like a “cross between a Concorde, a rail gun, and an air hockey table,” Musk said at the D11 Conference in May.

And, Musk being Musk, it’s fast — designed to travel an insane 800 mph, making the San Francisco-to-Los Angeles run in just 30 minutes. It’s called the “Hyperloop,” and it’s a magnetic levitation vehicle (possibly more like a car than a train) traveling friction-free in a vacuum tube.

It sounds like a new idea, but it isn’t. Early subway trains ran on compressed air. A physicist named R.M. Salter came up with what he called the Very High Speed Transit System in 1972, and described it as “electromagnetically levitated and propelled cars in an evacuated tunnel.” And a Colorado-based company called ET3 has been plugging away at just such a concept, with Chinese collaborators, for more than a decade.   That's the ET3 pod below.

Generally, ideas like this have foundered because of a lack of money. Having ready cash isn’t billionaire Musk’s problem, so he may be able to make this work where others have failed. I like the fact that he plans to make the technology open-source, and is inviting collaboration to improve the design.

Musk’s concept, skeletal as it is right now, sounds quite a bit like ET3’s. But Tesla Motors spokeswoman Shanna Hendriks denies any collaboration. “There is no coordination between ET3 and Elon at this time,” she said. “Elon will be issuing a blog post about his idea for Hyperloop on August 12.”

Oster says about Musk, “Let him announce what he’s going to in his own way. There’s a lot of misinformation out there. I can’t comment on Hyperloop, but he’s going to be speaking more about it next month.”

Musk claims his Hyperloop will be able to do the six-hours-by-car San Francisco to Los Angeles run in half an hour. “What you want is something that never crashes, that’s at least twice as fast as a plane, that’s solar-powered and that leaves right when you arrive, so there is no waiting for a specific departure time,” Mr. Musk told Bloomberg last year.

And that’s pretty close to what ET3 has in mind. Daryl Oster, founder and CEO, said in an interview that he envisions something like “space travel on earth.” Lightweight five-seat passenger capsules (weighing just 400 pounds) that “look something like Red Bull cans” travel inside five-foot diameter air-free tubes at initial speeds of 370 mph or more. Airlocks (shades of Star Trek!) at the stations keep the vacuum in place.

Oster thinks a heady 4,000 mph is possible with the system, which means that if an international link is built, across the Bering Strait, New York to Beijing in two hours is possible. The electric vehicles are automated, and hooked into freeway-like networks. The vacuum tunnels can mostly run above the ground, but Oster said that for really high-speed travel—above 800 mph, for instance—they need to be underground.

The infrastructure could be built into highway medians or in existing state-owned right of ways.

Oster claims he can provide 50 times more transportation value per kilowatt-hour than proposed high-speed rail networks, and 50 times less carbon production than “the most efficient electric car or electric train.” He says he’s close to breaking ground soon on a $20 million three-mile test track, which will be located somewhere in the U.S.—California, Nevada, Colorado, Texas, Florida, South Carolina and some Canadian locations are possibilities. Why three miles? It takes a mile to get up to speed, a mile to coast, then a mile to slow down and stop.

ET3 is an international effort, with 256 licensees in 19 countries, Oster said. “We lived in China for five months getting the project off the ground there,” Oster said. “The Chinese are way ahead of everybody else with this technology.”

How can we not be intrigued by these lovely science-fiction visions of our transportation future? Here’s some ET3 video:

Related on MNN: Hyperloop would transport people at 4,000 miles per hour

Jim Motavalli ( @jmotavalli ) writes about cars, technology and the environmental world to anyone curious enough to ask.

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