Content
Introduction
Hyperloops have first been mentioned as a potential transportation technology in 1810 and have become one of the most infamous future transportation technologies, ever since Elon Musk, founder of Tesla, brought it back to the public’s attention in 2013 [1]. Proponents believe that hyperloops are the solution to many of today’s transportation problems - especially for distances of up to 1,500 kilometres - while opponents consider the costs, technical hurdles, and required efforts too large to be balanced out by the potential benefits [2]. Development efforts are particularly concentrated in Europe and Asia, leading almost 80% of all active hyperloop projects [3] involving both public (e.g. Technical University Munich, Technical University Delft, Massachusetts Institute of Technology, etc.) and private stakeholders (Virgin Hyperloop, Hardt, Hyperloop Transportation Technologies, etc.) [3].
The following sub-chapters will further discuss hyperloops, their technical characteristics as well as potential benefits and disadvantages.
Technologies
Urban
As the pods need a substantive amount of time to accelerate and de-accelerate, Hyperloop transportation systems (HTS) are not applicable for short distance and thus urban travel [4].
Long Distance
There are different technical solutions to create hyperloops, most of which combine technologies known from high-speed railways, aviation and aerospace applications [3]. Hyperloops always refer to low-drag, low-pressure tunnel systems - either over- or underground - that contain pods, driving through the tubes at supersonic speeds. This would make hyperloops two to three times faster than high-speed trains and ten to 15 times faster than regular trains [5]. Most developments rely on a quasi-vacuum being built up by pumps within the tunnel [6]. The vacuum is critical to reach subsonic or near-sonic speeds as air or frictional resistance would slow the pods down. In order to maintain the vacuum, all stations must consist of three parts: an arrival chamber which is de-vacuumed when a pod enters the station, an embarking zone with normal atmospheric pressure as well as a departure chamber where the vacuum is re-created before the pod is led back into the tube system. All of these components are separated by hermetic doors [6]. However, maintaining a vacuum still represents a big challenge especially over large distances and with multiple station gateways between start and destination [1], [2], [4].
So far, most prototypes are powered by linear induction motors. The pods hover through the airless tunnels, either on air cushions or on magnetic fields. If the tunnels are built above the ground, they will be equipped with solar panels to produce energy for the hyperloop [1].
HTS are currently considered an auspicious alternative to short-haul flights, promising less travel time and less fuel consumption per passenger revenue kilometer as well as high safety standards [4], [5], [6]. Developers envision recreate the atmosphere found in outer-space within the tubes with a pressure 99% lower than on the earth’s surface. Airplanes consume significant amounts of energy to reach low-pressure altitudes. By creating and maintaining a low-pressure atmosphere within the tubes, the pods could reach high speeds without consuming much energy. According to studies conducted by the National Aeronautics and Space Administration (NASA) hyperloops would be five to six times more efficient than short haul flights and approximately twice as efficient as rail transportation [5]. However, a comprehensive hyperloop solution fulfilling the promises of high speeds and low costs and withstanding the reality check is yet to be designed, built and tested [4], [6].
Business Models
It seems to be a little too early in the development process of hyperloops to define potential business models. However, there are some potential use cases to be mentioned here.
Elon Musk planned to build a “Chicago Express Loop”, a tunnel system for high-speed busses connecting the city center of Chicago with the Chicago o’Hare airport. The project was to be executed, financed and run by Musk’s tunnel-building company “The Boring Company” with a planned operation starting in 2021. The busses were planned to reach a maximum speed of 200 km/h, carry eight to 16 passengers at a time and serve in 30-second intervals for 20 hours per day. Musk also envisions the pods to be mobile online shops and entertainment systems, providing travellers with a memorable experience [7]. But the Chicago Express Loop was never inaugurated, let alone built [8].
Instead, Musk built the “Vegas Loop”. A high-speed tunnel system connecting the convention centers in Las Vegas that cost $40 million. While the Vegas Loop was inaugurated in April of 2021, it does not fulfil its initial promises yet: the entrepreneur promised autonomous Teslas with top speeds of 240 km/h, transporting up to 4400 passengers per hour. In reality, person-driven Teslas operate in the tunnel at top speeds of merely 65 km/h as the tunnel’s length and width are insufficient for the cars to go faster [9].
But Elon Musk is not the only one believing in the potential of hyperloops. There are numerous start-ups, especially in the United States of America and Europe, that are working tirelessly to make hyperloops the next big thing in the transportation industry. The Dutch company “Hardt” is planning to employ hyperloops with a maximum speed of 700 km/h for goods transportation in 2025 and for people transportation in 2028. They plan to build five international trajectories, connecting Amsterdam to other regions in the Netherlands as well as Brussels, Paris, and Dusseldorf [1], [10].
Another important figure in the hyperloop realm is Richard Branson, founder of Virgin Hyperloop. They were the first ones to conduct a manned test drive in a hyperloop tunnel. Although the pod only reached a maximum speed of around 140 km/h, they plan to start commercial operations by 2030 [10]. Virgin Hyperloop also plans to inaugurate a hyperloop transportation system in India, connecting the cities of Mumbai and Pune and thus potentially creating a new economic mega-region. The Indian government supports the public infrastructure project and certification is expected by 2025. Such infrastructure projects not only create new jobs - in this case an estimated 1.8 million and socio-economic benefits, mounting to as much as $36 billion over its lifetime. It also expands the working and living opportunities for society, granting citizens access to a larger pool of jobs, housing, healthcare institutions, education, and much more [11], [12].
However, the success of these projects largely depends on international and national institutions’ willingness to invest [10].
Political Topics / Constraints
Hyperloops are currently highly debated in technology, society and politics. For one thing, opponents say that hyperloops do not offer any explicit advantages compared to high-speed trains. The realization of hyperloops is defined by numerous conflicts of objectives. On the one hand, they require extreme investments in research and development and the required infrastructure but on the other hand, hyperloops cannot successfully transform the mobility of the future if they are not affordable to the majority of society. Some experts expect the construction costs to outweigh the potential economic benefit that could be brought about by HTS [4], [5], [11]. The design of tubes and capsules poses another conflict: wider tubes decrease the drag forces of the capsules inside but the larger the tubes, the more operational energy and infrastructure costs increase [4].
For another, the technical challenges remain considerable. Hyperloops are still defined by many unknowns and research literature on critical technologies like magnetic levitation and electric propulsion are currently too immature for the proposed speed range [4]. The list of theoretical as well as practical question marks is long: depressurizing the tube and maintaining a vacuum over long distances with multiple stations between start and destination, the influence of weather, climate, earthquakes, or thermal movements, on the circumstances within the tunnels, understanding aerodynamic phenomena inside the tubes, etc. So far, there is no substantial evidence proving the promises made by stakeholders. No company has been able to conduct a test drive in the proper environment for over 0.5 kilometers as there are no full-scale tube systems and testing facilities. This further limits the progress of testing and development [3], [4].
Although it is widely believed that HTS will be the most energy efficient means of transportation, evidence is yet to be found. The vacuum pumps that many prototypes employ consume a vast amount of energy. Most developers of HTS plan to equip the tubes with solar panels for the system to create its own energy [6]. However, there are no detailed insights into the feasibility of renewable energies as a sufficient power source for this energy-intensive transportation system [3], [5].
In addition, hyperloop routes must be developed individually, according to the regional environment, topography and circumstances: flat landscapes are far more suitable for the application of HTS than landscapes defined by hills. Dense urban spaces, high land values as well as protected landscapes further complicate the development of HTS and significantly influence the implementation costs [2], [4], [5], [11]. This is the reason why some experts recommend pursuing the development of supersonic planes instead, as this would not require building an entirely new global infrastructure [2]. Furthermore, hyperloops still face a lack of support within society. So far, there has only been one manned test-drive conducted by Virgin Hyperloop, a hyperloop development company founded by business mogul Richard Branson. While the test is labelled a success, the pod only reached a maximum speed of 140km/h instead of the 700km/h that are planned for this mode of transportation [10]. It has yet to be found out whether humans are affected by those high speeds and the vacuum within the tunnel.
Furthermore, the current railway communication systems are based on the LTE-network which is not compatible with the planned top speeds of HTS [3].
Building the tube systems below the surface - which might be required in certain topographies - would also complicate maintenance and emergency evacuation and affect capital costs [5].
Moreover, hyperloops do not fit into regulatory guidelines of any transportation mode existing today and so far, legal and risk aspects have not been evaluated sufficiently: only 12% of all Hyperloop studies conducted in the EU have explored such issues [3], [11]. Policymakers must therefore deem hyperloops worthy of being pursued and start developing regulatory frameworks and technical standards. An improvement of development progress also depends strongly on collaborations between private and public entities [3]. Institutions of the EU do not seem to want to rule out hyperloops categorically - despite the above mentioned challenges and limitations. At the beginning of 2020, they agreed to set up regulations and standards to move forward with hyperloops in Europe [1]. In the United States, the Department of Transportation decided in July 2020 that hyperloop could be governed under the authority of the Federal Railroad Administration. This is a decisive decision for hyperloop development in the US as it made such projects eligible for federal funding [13].
All in all, HTS currently do not have a sufficient scientific foundation to make statements about the technology’s feasibility and potential. There are no reliable estimations on the required investments for infrastructure, electrification and maintenance which significantly influences the technology’s affordability and profitability [4].
Consumer Perspective
The impact of hyperloop transportation on passengers is one of the least examined aspects of HTS. A first manned test-drive was conducted by Virgin Hyperloop in 2020, but at a top speed of only 140km/h which is far from the promised maximum speed [10]. Passenger safety and comfort must obviously be a top priority in the development of HTS but until now, developers cannot know how acceleration and deceleration - especially in curves - as well as vibratory effects influence the passengers. Being locked into a pod within a tube with no possibility to see the outside could also create psychological distress and motion sickness [3], [5]. Furthermore, current pod design shows that passengers are not meant to walk around in the vehicle during transit and most prototypes are planned without facilities which can negatively influence passenger comfort [6]. The fact that HTS are entirely secluded from other transportation infrastructure as well as wildlife and other external influencing factors could potentially make it a particularly safe mode of transportation [5] but the success of this new technology widely depends on consumer acceptance [3].
Sources
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[8] Chicago Tribune (2020, October 14). Elon Musk's plan for express transit to O'Hare went nowhere, but Boring Co. Says concept could happen in Vegas. Chicago Tribune. Retrieved from https://www.chicagotribune.com/business/ct-biz-elon-musk-hyperloop-las-vegas-20201014-asq4yai5qvdkhlhxfzyahq6sm4-story.html
[9] Knecht, J. (2021, April 12). Teslas, die durch Tunnel tröpfeln. auto motor sport. Retrieved from https://www.auto-motor-und-sport.de/tech-zukunft/mobilitaetsservices/tesla-boring-company-las-vegas-convention-center-loop-kritik/
[10] Janczura, S. (2021, January 6). Hyperloop: Warum die fliegenden Holländer allen davon rasen. Retrieved from https://www.ingenieur.de/technik/fachbereiche/verkehr/europas-erster-hyperloop-ist-fertig/
[11] Wadke, R. (2020, November 1). Pune-Mumbai Hyperloop Project will be the largest privately-funded transport infrastructure'. The Hindu Business Line. Retrieved from https://www.thehindubusinessline.com/news/national/pune-mumbai-hyperloop-project-will-be-the-largest-privately-funded-transport-infrastructure/article32998400.ece
[12] Variyar, M. (2020, October 30). Hyperloop in Mumbai-Pune, Bengaluru may be ready by 2029, says Virgin Hyperloop One. CNBC TV18. Retrieved from https://www.cnbctv18.com/india/hyperloop-in-mumbai-pune-bengaluru-may-be-ready-by-2029-says-virgin-hyperloop-one-7344571.htm
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