How Elon Musk’s Hyperloop Could Change Public Transport

Imagine driving from Los Angeles to San Francisco in less than an hour without leaving the ground. It’s not exactly teleportation, but the next best thing.

From the man who gave us PayPal, Tesla and SpaceX, this is the Hyperloop, a whole new mode of transportation.

What it is?

The California High-Speed ​​Rail, a mass transit system due to be completed by 2029, will carry passengers between 24 stations on an 800-mile route at 200 miles per hour. The only problem? The train in question will be noticeably slower, more expensive and more dangerous than flying. The entire project will take years, and is widely regarded as a miracle.

Elon Musk has the best idea.

At the PandoDaily event in 2012, Musk proposed a «fifth mode of transportation» called the Hyperloop. He described the concept as being immune to weather and crashes, with an average speed twice that of a typical aircraft. low energy requirements and 24-hour work opportunities.

Musk was initially very vague in his description, but since then we’ve learned a lot about Hyperloop and the technology behind it — and it’s almost ready for testing.

How it works

Elon Musk’s Hyperloop will operate from San Francisco to Los Angeles, moving passengers at speeds up to 800 miles per hour. Instead of driving for five-plus hours, you would spend about an hour on a Hyperloop «pod» that would travel through a tube containing a very special environment.

Let’s talk about what this entails.

Musk and his team looked at several ways to make this technology work. The first was an enlarged version of the old pneumatic tubes used to send packages inside and between buildings. “In principle, you could use very powerful fans to force air at high speed through a pipe and move man-sized pods from Los Angeles to San Francisco,” Musk writes. «However, the friction of a 350-mile column of air moving at near the speed of sound against the inside of the tube is so great that it is impossible for all practical purposes.»

They also considered using a vacuum environment with electromagnetic suspension. According to Musk, “The problem with this approach is that it’s incredibly difficult to maintain a near-vacuum in the room, let alone 700 miles (round trip) of a big pipe with dozens of station locks and thousands of containers coming in and out every day. , All it takes is one leaking seal or a small crack somewhere in hundreds of miles of pipe and the whole system stops working.”

With this in mind, the team settled on a mid-range solution: a low pressure system where standard commercial pumps can easily overcome the leak. However, other problems begin to arise with the air in the capsule. Namely, the Kantrowitz limit — «nature’s law of maximum velocity for a given ratio of tube area to pod» — forces you to either move slowly or have a tube of enormous diameter. Otherwise, the capsule will behave like a syringe, pushing the entire column of air through the system. To get around this problem, Musk came up with a clever workaround: install an electric compressor fan at the nose of each capsule that actively transfers pressure from the front to the back of the vessel, cheating the Kantrowitz constraint.

It also solves another problem, which is how to hang the pods with as little friction as possible. If each pod produces and rides on an air cushion (think of an air hockey table), friction will stay low and the tube will be easier to build because it won’t have to hang the pods on its own.

In terms of power, Musk says the battery pack will work with an electric compressor fan, and an external linear electric motor (similar to the one used in the Tesla Model S) will speed up the suspension, elevating it every 70 miles or so.

Expenses

New infrastructure is always expensive. But according to Musk, the pods and motors are relatively inexpensive (several hundred million dollars at most) compared to the tube itself, which can cost several billion dollars. However, the Hyperloop is still outperforming the California High-Speed ​​Rail, which will cost several tens of billions of dollars.