Proponents claim the concept will be faster than air travel, transporting travellers directly from one city centre to another at speeds of up to 1,000 km/h (620 mph).
This would cut travel time from Pune to Mumbia in India—one of the first proposed hyperloop routes—to just 25 minutes. Hyperloops could also end up being safer than air travel, since the technology does not need moving parts or flammable fuel.
And if powered by renewably produced electricity, they would effectively have zero emissions. As it stands, though, the concept still faces significant challenges. One of these is that there is still no consensus on exactly how hyperloop systems should work.
The more than two dozen teams working on hyperloops around the world are divided on whether to use electromagnetic or electrodynamic suspension systems, for example, or whether pod propulsion should be by linear induction or linear synchronous motors.
A lack of standardisation on these areas could make it hard to connect hyperloop networks as well as hampering cost reductions that could come from manufacturing economies of scale.
Another problem for the concept is that there is no regulation around issues such as safety and certification. Also, hyperloops will require the construction of hundreds of miles of vacuum tubes. In built-up areas the tubes will have to go underground.
But to build the tunnels needed for these tubes will require a step change in tunnel boring capabilities. The Boring Company, which Musk founded specifically to create hyperloop tunnels, is aiming to create a tunnel boring machine that can move 10 times faster than a snail.
That may not sound like a lot, but it is still 40 or 50 times faster than what The Boring Company can achieve today.
Finally, because of the high speeds it will achieve, “you need thousands and thousands of tests before you can transport passengers with the hyperloop in a safe way,” said Pieter Becking, team captain at Delft Hyperloop, a Dutch development organisation.
Despite these challenges, hyperloop advocates remain convinced that the technology will work and that it could become widespread in time to help achieve global climate goals.
US-based Virgin Hyperloop, one of half a dozen or so companies developing hyperloops for commercial gain, trumpeted the first-ever passenger trial for the concept in November last year, whisking four passengers at up to 173 km/h (108 mph) along a 500 m (1,640 ft) tube.
And last month, Hyperloop Transportation Technologies (HyperloopTT), another US company, unveiled the first complete commercial Hyperloop system design.
“The world’s first full-scale hyperloop system integration is taking place at the HyperloopTT facility in Toulouse, France,” said company chief executive Andres De Leon. “In the coming months, testing will take place at all levels.”
Based on current rates of progress, we are “three to five years away from seeing a fully functioning system, assuming everything moves forward with the permitting and regulatory process,” he said.
However, it will still take a while to build the infrastructure. Becking said a timeframe of 15 years before hyperloops start to become widespread “is ambitious, but we think it’s definitely possible.”
Based on this prediction, by around 2035 hyperloops should start replacing short and mid-haul flights on routes such as Bangkok to Chiang Mai or Amsterdam to Paris. It remains to be seen if this will have an impact on emissions, however.
In theory, hyperloop’s zero-carbon energy use could lead to significant carbon emissions reductions, with HyperloopTT claiming up to a 143 million-ton saving from a system connecting Chicago, Cleveland and Pittsburgh in the US.
But in practice, the airline industry may have already largely eradicated its carbon footprint by the time Hyperloops enter operation. In February, British Airways said it could start using sustainable aviation fuel (SAF) on transatlantic flights as early as next year.
The company is aiming to blend conventional jet fuel with SAF produced from agricultural waste by LanzaJet, a US company whose investors include British Airways’ parent company IAG and the oil giant Shell. The airline hopes to cut carbon emissions by 70 per cent.
Also in February, the Dutch airline KLM trialled the use of SAF on a flight from Amsterdam to Madrid. And aircraft maker Airbus last year revealed three concepts for hydrogen-based zero-emission commercial planes that it said could enter service by 2035.
“I strongly believe that the use of hydrogen, both in synthetic fuels and as a primary power source for commercial aircraft, has the potential to significantly reduce aviation’s climate impact,” said Airbus chief executive Guillaume Faury in a press release.
Curbing aviation’s carbon emissions is not easy. But it is unlikely to be any more challenging than creating Hyperloops from scratch. And the global airline industry can afford to throw significant resources at the problem.
For this reason, it is unlikely that hyperloops could win out over air travel based on emissions alone. Supporters believe the big attraction for hyperloop users will be the ability to travel straight between city centres more quickly than jets can fly between airports.
Some say it’s high time to have such a mode of transport. “Hyperloop is a solution to a world that might be suffering from environmental collapse,” said John Grant, senior lecturer in sustainable construction and climate change at Sheffield Hallam University in the UK.
“If you’ve got an infrastructure that’s in a tunnel when you’re being hit by earth-shattering climate events, it just strikes me as being money in the bank,” he said.