Hyperloop technology is one of the most novel innovations in surface transportation. The concept is similar to the message tubes used in hospitals and large office buildings, with passenger or cargo pods operating at jetliner speeds inside evacuated tunnels. Hyperloop promises low emissions and downtown to downtown transportation between cities, but is it practical? After much hype, Richard Branson’s Virgin enterprise is divesting itself of hyperloop investment, and Elon Musk’s prototype tunnel in California has been dismantled. Is there a future for this technology? Jim Anderton comments.
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Moving people with greater speed and efficiency on land has always been about rail versus road. Putting trains into tunnels is a concept that goes back to Napoleon, and urban mass transit systems have made good use of the technology for well over a century.
It’s an intriguing idea, and one which thanks to Elon Musk and Virgin’s Richard Branson, absorbed a huge amount of consumer media attention. Small test panels have been built, and of course the basic engineering principles are obvious.
One of the big attractions of hyperloop is that the fundamental concept of moving capsules through vacuum tubes has been seen by millions of people in small-scale messaging applications in hospitals and office buildings.
From an engineering perspective, however, there are big questions that no one seems to be asking. I worked with moderate vacuum applications in vacuum impregnation systems for electronic components, and sealing large vacuum vessels is more difficult than it looks in applications where it’s necessary to open and close the vessel frequently.
Pumping down a large volume of air is no mean feat either. Operating vacuum pumps on the scale necessary to run a major transit system would be a major engineering challenge and will be both expensive and energy intensive. The tunnels themselves will be an engineering challenge, placing major demands on running from hoop stress to control of thermal expansion.
This will be very expensive as well. And of course, jet speed operates by the same basic economics in a hyperloop as it does in the air. To make it viable and popular, it has to operate over a long enough distance that the time differential from conventional transportation justifies the added cost.
Nobody flies 100 miles, and there are plenty of people that would drive or take a train to travel 400. More than that, and the jet makes sense. The hyperloop could too, except that building and maintaining hundreds of miles of tunnels and maintaining reasonable level of vacuum for commercial operations would be mind-bogglingly expensive, if it’s even technically feasible.
Running a system from an airport to an urban centre might be workable, but then there simply wouldn’t be enough time and space to exploit the high-speed capability of the hyperloop, making TGV or maglev alternates more sensible.
I just don’t see how this technology can possibly make economic sense. Reducing air pressure does increase travel speed, and Mother Nature very conveniently provides that soft vacuum up there, 30,000 feet up. And the major problem with air travel isn’t in the airliner, it’s in the hassle of getting to and from the airport and in airport security itself.
Autonomous flying taxis under development right now could take away the hassle of getting to the airport, and I expect that future scanning technologies will largely remove the bottleneck presented by the TSA in today’s terminals.
Is there any room for a hyperloop? Maybe, in a scaled-down form, perhaps for mail and small packages, like a scaled-up version of the systems used in hospitals today.
Elon Musk’s test hyperloop tunnel in California has been dismantled. Richard Branson has sold Virgin’s stake in their hyperloop project. If this technology has a future, it isn’t likely in moving people.
Musk continues to develop tunnel-based transportation projects with The Boring Company, so reducing traffic congestion by moving people underground is still in active development. But in the end, the basic rules of engineering design always prevail, and in my opinion, sucking the air out of the tunnel never really made sense.