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| ==Political and economic considerations== | ==Political and economic considerations== | ||
| Cost savings versus conventional rail are designed to come from a combination of several factors. Its small profile and elevated nature mean that it can travel for most of its journey down the median of the ] |
Cost savings versus conventional rail are designed to come from a combination of several factors. Its small profile and elevated nature mean that it can travel for most of its journey down the median of the ], with small detours when the highway bends too much. The low profile reduces tunnel boring requirements and the light weight of the capsules versus a train reduces track costs. It is assumed in the design paper that there would be less right-of-way opposition and environmental impact as well due to its small, sealed, elevated profile versus that of a rail easement.<ref name="AlphaSpaceX"/> | ||
| The Hyperloop alpha-design whitepaper suggests that {{USD|20}} of each one-way passenger ticket between Los Angeles and San Francisco would be sufficient to cover initial ], based on amortizing the cost of Hyperloop over 20 years with ridership projections of 7.4 million per year in each direction and does not include operating costs (although electric costs would be covered by solar panels). No total ticket '']'' was suggested in the alpha design.<ref name="AlphaSpaceX" /> | The Hyperloop alpha-design whitepaper suggests that {{USD|20}} of each one-way passenger ticket between Los Angeles and San Francisco would be sufficient to cover initial ], based on amortizing the cost of Hyperloop over 20 years with ridership projections of 7.4 million per year in each direction and does not include operating costs (although electric costs would be covered by solar panels). No total ticket '']'' was suggested in the alpha design.<ref name="AlphaSpaceX" /> | ||
Revision as of 20:21, 16 August 2013
A hyperloop is a proposed mode of high-speed transportation developed by the entrepreneur and SpaceX founder Elon Musk. Musk envisioned the system as a 'fifth mode' of transportation: an alternative to boats, aircraft, automobiles, and trains. Musk stated that it "could revolutionize travel".
A hyperloop employs an elevated tube through which capsules move. The tube is partially evacuated to reduce friction. The capsule rides on a cushion of air forced through multiple openings at the capsule's bottom, further reducing friction. The capsules would be propelled by linear induction motors placed at intervals along the route.
According to the initial "Alpha" design released on August 12, 2013, a hyperloop would enable travel from the Los Angeles region to the San Francisco Bay Area in 35 minutes, meaning that passengers would traverse the proposed 354 miles (570 km) route at an average speed of just under 598 mph (962 km/h), and a top speed of 760 mph (1,220 km/h). The suggested route runs from the northern San Fernando Valley to the Hayward/Castro Valley area, paralleling the Interstate 5 corridor for most of its length. The "Alpha" proposal estimates a US$6 billion budget for a passenger-only version of the system, while a version allowing for transportation of both passengers and cars would cost US$7.5 billion.
History
Musk first mentioned that he was thinking about a concept for a "fifth mode of transport", calling it the Hyperloop, in July 2012 at a PandoDaily event in Santa Monica, California. He described several characteristics of what he wanted in a hypothetical high-speed transportation system: immunity to weather, cars that never experience crashes, an average speed twice that of a typical jet aircraft, low power requirements, and the ability to store energy for 24-hour operations. Musk estimated at the time that the cost of the San Francisco-Los Angeles Hyperloop would be about US$6 billion, one tenth the cost of the proposed high-speed rail that would serve those cities.
Musk has likened the hyperloop to both a ground-based Concorde and a "cross between a Concorde and a railgun and an air hockey table", while noting that it has no need for rails. He believes it could work either below or above ground.
From late-2012 until August 2013, an informal group of engineers at both Tesla and SpaceX worked on the conceptual foundation and modeling of Hyperloop, allocating some full-time effort to it toward the end.
A high-level alpha design for the system was published on August 12, 2013, in a whitepaper posted to the Tesla and SpaceX blogs. Musk has also said he invites feedback to "see if the people can find ways to improve it"; it will be an open source design, with anyone free to use and modify it. The following day he announced a plan to construct a demonstration of the concept.
Related proposals
In 1812 the British mechanical engineer and inventor George Medhurst wrote a book detailing his idea of transporting passengers and goods through air-tight tubes using air propulsion.
In 1869 the Beach Pneumatic Transit was an early attempt to build a one-block-long demonstration prototype of an underground tube transport public transit system in New York City. The system worked at near-atmospheric pressure, and the passenger car moved by means of higher-pressure air applied to the back of the car while somewhat lower pressure was maintained on the front of the car.
In the 1910s, vacuum trains were first described by rocket pioneer Robert Goddard.
Swissmetro was a proposal to run a maglev train in a low pressure environment. Increasingly detailed studies beginning in 1987 found the project to be technically and economically feasible. The preliminary feasibility study done by Dornier Consulting GmBH in 1987 under commission from the Swiss Department of Transport resulted in a positive report in 1988; this led the Department to partially fund a followup study by the Swiss Federal Institute of Technology in Lausanne (EPFL) that also returned a positive result. In 1994, the main study was directed by Elektrowatt AG who worked with EPFL and was completed in 1998. Concessions were granted to Swissmetro in the early 2000s to connect the Swiss cities of St. Gallen, Zurich, Basel and Geneva; however, the vactrain was never built due to lack of political support. EPFL maintains the Swissmetro archives.
Theory and operation
Developments in high-speed rail, and high-speed transport more generally, have historically been impeded by the difficulties in managing friction and air resistance, both of which become substantial when vehicles approach high speeds. The vactrain concept eliminates these obstacles by employing magnetically levitating trains in tubes kept at a complete vacuum, allowing for theoretical speeds of thousands of miles per hour. The high cost of maglev, however, and the difficulty of maintaining a vacuum over large distances, has prevented this type of system from ever being built. The Hyperloop can be viewed as a modified vactrain, employing more cost-effective solutions to the same problems the latter was designed to solve.
The Hyperloop operates by sending specially designed "capsules" or "pods" through a continuous steel tube maintained at a partial vacuum. Each capsule floats on a 0.5–1.3 millimetres (0.020–0.051 in) layer of air provided under pressure to air-bearing "skis", similar to how pucks are suspended in an air hockey table, thus avoiding the use of maglev while still allowing for speeds which wheels cannot sustain. Linear induction motors located along the tube accelerate and decelerate the capsule to the appropriate speed for each section of the tube route. With rolling resistance eliminated and air resistance greatly reduced, the capsules are able to glide for the bulk of the journey. In the Hyperloop concept, an electrically-driven inlet fan and air compressor are placed at the nose of the capsule "actively transfer high pressure air from the front to the rear of the vessel," resolving the problem of high speed transport in a tube that is not a hard vacuum wherein pressure builds up in front of the vehicle, slowing it down. A fraction of the air is shunted to the skis for additional air pressure, augmenting that gained passively from lift due to their shape.
Capsules will reach a top speed of 760 mph (1,220 km/h) so as to maintain aerodynamic efficiency, and passengers will experience a maximum inertial acceleration of 0.5 g, well less than a commercial airliner on takeoff and landing. At those speeds, there would not be a sonic boom; with warm air inside the tubes and high tailwinds, the pods could travel at high speeds without crossing the sound barrier.
Notional route
The notional route for the Los Angeles to San Francisco system used in the alpha design document would begin around Sylmar just south of the Grapevine, approximately follow the I-5 highway to the north, and arrive at a station near Hayward on the east side of San Francisco Bay. It is planned to be built near the interstate in order to keep prices for the building area down. Several conceptual extension routes were also shown in the alpha design document, including Sacramento, Anaheim, San Diego, and Las Vegas. This routes will be built if the hyperloop will also transport cargo.
Political and economic considerations
Cost savings versus conventional rail are designed to come from a combination of several factors. Its small profile and elevated nature mean that it can travel for most of its journey down the median of the I-5 highway, with small detours when the highway bends too much. The low profile reduces tunnel boring requirements and the light weight of the capsules versus a train reduces track costs. It is assumed in the design paper that there would be less right-of-way opposition and environmental impact as well due to its small, sealed, elevated profile versus that of a rail easement.
The Hyperloop alpha-design whitepaper suggests that US$20 of each one-way passenger ticket between Los Angeles and San Francisco would be sufficient to cover initial capital costs, based on amortizing the cost of Hyperloop over 20 years with ridership projections of 7.4 million per year in each direction and does not include operating costs (although electric costs would be covered by solar panels). No total ticket price was suggested in the alpha design.
Political impediments to the construction of such a project in California will be very large. There is a great deal of "political and reputational capital" invested in the existing mega-project of California High-Speed Rail. Replacing that with a different design would not be straightforward given the California political economy. Moreover, the alpha-level cost estimates of the Hyperloop itself are considered unlikely to "be immune to the hypertrophication of cost that every other grand infrastructure project seems doomed to suffer."
An alternative location, with a more amenable political and economic environment, has been suggested in Texas.
Building a successful Hyperloop sub-scale demonstration project could reduce the political impediments and improve the accuracy of cost estimates. Musk has suggested that he may be personally involved in building a demonstration prototype of the Hyperloop concept, including funding the development effort.
See also
- Maglev
- Pneumatic tube
- Ground effect train
- Kantrowitz limit
- Megascale engineering
- Cable transport
- Vactrain
- Atmospheric railway
- Swissmetro
References
- Garber, Megan (July 13, 2012). "The Real iPod: Elon Musk's Wild Idea for a 'Jetson Tunnel' from S.F. to L.A." The Atlantic. Retrieved September 13, 2012.
- ^ Musk, Elon (August 12, 2013). "Hyperloop Alpha" (PDF). SpaceX. Retrieved August 13, 2013.
- ^ Pensky, Nathan; Lacy, Sarah; Musk, Elon (July 12, 2012). PandoMonthly Presents: A Fireside Chat with Elon Musk. PandoDaily/YouTube.com. Event occurs at 43:13. Retrieved September 13, 2012.
- Gannes, Liz (May 30, 2013). "Tesla CEO and SpaceX Founder Elon Musk: The Full D11 Interview (Video)". All Things Digital. Retrieved May 31, 2013.
- Rose, Kevin (September 7, 2012). "Foundation 20 // Elon Musk". YouTube.com. Retrieved September 13, 2012.
- Staff; Musk, Elon (June 18, 2013). Tech Summit 2013: Tesla's Musk gears up for sales battle. Reuters Insider. Event occurs at 38:49-43:12. Retrieved June 21, 2013.
- ^ "Musk announces plans to build Hyperloop demonstrator". Gizmag.com. August 13, 2013. Retrieved August 14, 2013.
- Musk, Elon (August 12, 2013). "Hyperloop". Tesla. Retrieved August 13, 2013.
- Mendoza, Martha (August 12, 2013). "Elon Musk to reveal mysterious 'Hyperloop' high-speed travel designs Monday". The Globe and Mail. Retrieved August 12, 2013.
- Anderson, Chris C. (July 15, 2013). "If Elon Musk's Hyperloop Sounds Like Something Out Of Science Fiction, That's Because It Is". Business Insider. Retrieved August 14, 2013.
- "The Pneumatic Tunnel Under Broadway, N.Y.". Scientific American. March 5, 1870.
- ^ "The Future of Transport: No loopy idea". The Economist. Vol. Print edition. 2013-08-17. Retrieved 2013-08-16.
- "History". Swissmetro.ch. Retrieved August 14, 2013.
- Vance, Ashlee (13 August 2013). "Revealed: Elon Musk Explains the Hyperloop, the Solar-Powered High-Speed Future of Inter-City Transportation". Bloomberg Businessweek. Retrieved 13 August 2013.
External links
- Tesla Motors: Template:PDFlink
- SpaceX: Template:PDFlink