A solar-powered, city-to-city transportation system that runs at 800 mph and sells passenger tickets cheaper than Amtrak. That's the Hyperloop vision of Elon Musk, founder of Tesla Motors and SpaceX and co-founder of PayPal, who unveiled his concept Monday after more than a year of speculation about what he had in mind.
Musk had dropped hints over the last year about his concept, so there was more than a little anticipation. According to Musk, the Hyperloop would be cheaper to build, safer, more resistant to earthquakes and less "disruptive to those along the route" than other forms of transportation. He has also said the Hyperloop would never crash, was immune to weather, would go three to four times faster than a bullet train and would have an average speed twice that of an airliner.
He told news media that a Hyperloop connecting Los Angeles and San Francisco could be built as an elevation that follows I-5, so that farmers would have access to their land between the columns.
The Kantrowitz Limit
To ride on this train, you'd sit in an aluminum pod that is traveling through a low-pressured steel tube. The pods use magnetic linear accelerators to get started, with occasional boosts from external linear electric motors. Then the pods would float on air, propelled by a powerful fan at the front of the pod that pushes air to the rear. Solar panels on the top of the tube, Musk said, would generate energy "far in excess of the energy needed to operate" the system.
The electric compressor fan on the pod's nose would also be needed to overcome something called the Kantrowitz limit. This is a minimum tube-to-pod area ratio, Musk said, "below which you would choke the flow" because the pod would end up pushing the entire column of air in the system as if it were pushing fluid through a syringe -- thus slowing it down. The air-cushion part of the concept has been compared to the pneumatic tubes used to shuttle capsules of paperwork around in old buildings.
A Mere $6 Billion
Musk envisions Hyperloop pods leaving a station every half-minute, each containing 28 people, and that the cost for the system along the Los Angeles-to-San Francisco route would be a mere $6 billion. By comparison, the proposed high-speed rail system that is intended to run between San Francisco and Los Angeles at 200 miles an hour would cost $69 billion, and would not be completed until 2029 at the earliest.
Musk said that, given his day jobs of helping to create the electric car industry and the commercial space travel industry, he's too busy to actually undertake this Hyperloop project, but he hopes someone will. He has issued a 57-page PDF explaining what he calls this alpha version, and has promised to release an open-source design that can be used by anyone willing to undertake the project.
Joao De Sousa:
Posted: 2013-08-21 @ 3:31pm PT
Great stuff. Let's put it to work, in action.