The following is a proposal I wrote for my second-year architecture project. I think it does a good job of summarizing the idea of maglev trains in the United States.
The future of human energy production will likely be decided in the 21st century. We are sure to run out of accessible fossil fuels within a few generations, but promising projects for alternative energy sources are already underway. Development of new energy sources depends on complex political, economic, and social forces, and change to more sustainable power will come gradually and unevenly throughout the world. Transportation is one of the key industries that will be greatly affected by this change. What follows is an examination of the merits, drawbacks, costs, and feasibility for an emerging form of transportation, magnetic propulsion, which may become the dominant form of human movement within the next few centuries.
Magnetic propulsion holds promise for the future of transportation for a number of reasons, but first we must examine its current technological state and how it is has thus far been implemented. Magnetic levitation is the effect of an object being supported only by magnetic fields. The first patents issued for magnetic levitation transportation systems were made in the early 20th century. By controlling the electric current within a magnet, the magnet’s repulsiveness or attractiveness to other magnets can be controlled. Magnetic transportation is primarily concerned with trains; unlike conventional trains that run on tracks, magnetic levitation (maglev) trains employ powerful magnets to float above a guide rail. Magnets are located within the train units and the track; the latter are switched on and off or alternate current as the train approaches to pull the vehicle forward, providing magnetic acceleration. This will be explained in further detail later.
Maglev trains have the primary advantage of speed, efficiency, and silence. They have the potential to relieve local and regional road and airport congestion, and the technology already exists and is in use today in several countries. Because the train makes no contact with the track at high speeds, the only drag occurs from air resistance, allowing for speeds upward of 580 kilometers per hour; theoretically, maglev trains could obtain speeds of up to 6,400 km/h in evacuated tunnels. Maglev trains would dramatically reduce travel times regionally. Additionally, the absence of rolling resistance eliminates the need for an on-board engine, increasing power efficiency. On-board train systems (lighting, climate control, etc.) are powered from the track through induction. Because the maglev train makes no contact with tracks, they produce little noise compared to conventional trains. The first official passenger maglev train opened in 1979 in Hamburg, Germany as part of an exhibition. Today, there are full service maglev lines running in Japan, China, and South Korea.
There are also several drawbacks to maglev transportation, including cost, infrastructure, and weight. Because maglev trains cannot operate on existing track, they require an entire new infrastructure system of tracks. The way the train interlocks with the track makes any kind of system other than point to point difficult to construct. Their high speeds usually necessitate that the tracks are elevated above roadways and other obstacles for safety reasons. However, trains can be designed to be used with existing railway stations and facilities if current track is built over. The capital costs involved with a maglev system are significant, and systems such as the one in Shanghai are not able to recuperate initial investment. A proposed Baltimore-Washington line would cost 69.3 million dollars per kilometer. High ridership could offset these costs. Finally, massive magnets are needed to support to large weight of a maglev train, which becomes a major design issue. Research is currently underway to increase the efficiency of magnets and how to use less power to support the magnetic fields.
Another issue with maglev transportation is the method of levitation. There are two types of magnetic levitation; electromagnetic suspension (EMS) and electrodynamic suspension (EDS), the latter of which is still experimental. In EMS, the body of the vehicle wraps around the steel guideway, where the train’s guidance magnets levitate the train horizontally and levitation magnets vertically. The train is pulled forward by a traveling electromagnetic field in the track. This system is inherently unstable, so on-board electronics must constantly monitor the train’s distance from the track and adjust for irregularities. On the other hand, this system can operate at any speed, simplifying the design of the track. Comparatively, EDS systems only work at minimum speeds of 30 km/h, requiring a secondary system built in to the entire track for low speeds (steel wheel is a possibility, used when entering and exiting stations). In this system, the train floats above the track via magnetic forces from the train and track. The repulsion between the train and track is stable and requires no automatic feedback. Alternating current in the track pulls the train forward.
In relation the electric highway project, magnetic propulsion could be applied as an alternative form of road transport or as an additional system integrated with the highway. As personal transportation, private vehicles could be fitted with normal wheels (or whatever form they may have in the future) in addition to a system that can hook into an automated maglev highway. A simpler proposal is to integrate a maglev system with highways as we know them today, providing an alternative for passenger and freight transport. Attaining high speeds, the maglev system would reduce the highway system to that of private transport for short distances. Maglev trains could take freight and people across large distances within a few hours, greatly reducing transportation costs. In conventional systems, maglev trains may be outrun by air transport, but maglev systems have the potential for much higher capacity due to frequency. As a public transportation system, maglev transit would likely become quite popular, especially in regional areas of the United States like the northeast and southwest, for its high speeds. International maglev trains, such as the proposed mid-Atlantic tunnel, would also greatly increase global interdependence. Maglev systems would be very energy efficient, not needing fuel of its own but electricity from power plants – perhaps wind, solar, and hydro power plants could be placed along the route of the maglev line to exclusively power it, especially in open country. As a very basic concept, magnetic propulsion technology could eventually be used to launch payloads into space.
The environmental and human benefits from local, regional, and national magnetic levitation transportation systems would outweigh the costs and technical hurdles that are currently associated with them. As the world runs out of economically recoverable oil (predicted to happen by mid-century), humanity will have to cope with less fuel or step up and increase power from alternative energy sources. Fortunately, the world currently gets 19% of its energy from alternative energy. Maglev transportation will efficiently use that energy to move commerce, goods, and people around the world.
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