Timely capsules

Imagine a rapid transit system that takes you from San Francisco to Los Angeles in 30 minutes for less than $30 one way; or lets you commute from Houston to San Antonio in under 20 minutes for a mere $15. A crowd-sourced California startup believes it can build such a transportation system—based on Tesla and SpaceX founder Elon Musk’s Hyperloop concept. The hope, which some say is impractical, is that within 10 years it could connect major cities with safe and affordable public transportation.

In December, Hyperloop Transportation Technologies (HTT), a crowd-funded research and development company formed in 2013, released a 76-page report documenting its research into the engineering, safety, cost, and other issues that must be addressed to make Hyperloop a reality.

“When the California ‘high speed’ rail was approved, I was quite disappointed, as I know many others were too,” wrote Musk in 2013. “How could it be that the home of Silicon Valley and JPL … would build a bullet train that is both one of the most expensive per mile and one of the slowest in the world?”

The proposed San Francisco to Los Angeles “bullet train” would cost an estimated $200 million per mile to build. The HTT report estimates “that it’s absolutely feasible” to build a Hyperloop line between these two cities for $20 million to $45 million per mile.

Hyperloop isn’t a train. It’s a tube-based system in which magnets and electric compressor fans propel capsules containing up to 28 passengers each. Its projected cruising speed is as high as 700 miles per hour—almost as fast as a supersonic plane.

Hyperloop would be above the ground on pylons, and the tubes could come in prefabricated sections—features that HTT researchers believe will keep construction costs down. Lower construction costs would mean affordable ticket prices for fast, inexpensive intercity travel.

Critics have challenged Musk’s claims about the low costs of the project and have raised concerns about safety during emergency stops. One other caution: Passengers wouldn’t be able to leave their seats during trips, meaning any “bathrooms” would have to be built into the seats.

Elevating efficiency

Ever notice how very tall office buildings have lots of elevators? That’s because, with the high demand of a bustling office tower and only one car per elevator shaft, you need lots of shafts.

But all that may be about to change. Elevator manufacturing giant ThyssenKrupp AG is rolling out a cable-free elevator that would allow multiple cars to run in the same shaft, much like the trains that move airport passengers from the terminal to the gate. Since the ThyssenKrupp design also allows cars to move sideways and diagonally, buildings with such elevators might need only two shafts, one for going up and the other for descending.

Reducing the number of elevator shafts would not only improve the economics of skyscrapers (less space for elevators means more leasable space), it would allow architects and developers to design even taller buildings.

“Skyscraper heights are always limited by the fact that the shafts take up more and more space” the higher buildings go, said Daniel Levinson Wilk of the Fashion Institute of Technology, who studies the history of elevators, in The Wall Street Journal. —M.C.