Maglev train

High-speed maglev comparison with conventional high-speed trains

• Speed: Maglev allows higher top speeds than conventional rail. While experimental wheel-based high-speed trains have demonstrated similar speeds, conventional trains will suffer from friction between wheels and track, thereby increasing maintenance costs at such speeds, unlike levitated maglev trains.
• Maintenance: Maglev trains currently in operation have demonstrated the need for minimal guideway maintenance. Vehicle maintenance is also minimal (based on hours of operation, rather than on speed or distance traveled). Traditional rail is subject to mechanical wear and tear that increases rapidly with speed, also increasing maintenance. For example, the wearing down of brakes and overhead wire wear have caused problems for the Fastech 360 rail Shinkansen. Maglev would eliminate these issues.
• Weather: In theory, maglev trains should be unaffected by snow, ice, severe cold, rain, or high winds. However, as of yet, no maglev system has been installed in a location with such a harsh climate.
• Acceleration: Maglev vehicles accelerate and decelerate faster than mechanical systems regardless of the slickness of the guideway or the slope of the grade, because they are non-contact systems.
• Track: Maglev trains are not compatible with conventional track, and therefore require custom infrastructure for their entire route. By contrast, conventional high-speed trains such as the TGV can run, albeit at reduced speeds, on existing rail infrastructure, thus reducing expenditure where new infrastructure would be particularly expensive (such as the final approaches to city terminals), or on extensions where traffic does not justify new infrastructure. John Harding, former chief maglev scientist at the Federal Railroad Administration, claimed that separate maglev infrastructure more than pays for itself through higher all-weather operational availability and nominal maintenance costs. These claims have yet to be proven in an intensive operational setting, and they do not account for the increased maglev construction costs. However, in countries like China, there are discussions of building some key conventional high-speed rail tunnels/bridges to a standard that would allow them to be upgraded to maglev.
• Efficiency: Conventional rail is probably more efficient at lower speeds. But due to the lack of physical contact between the track and the vehicle, maglev trains experience no rolling resistance, leaving only air resistance and electromagnetic drag, which can improve power efficiency. Some systems, however, such as the Central Japan Railway CompanySCMaglev use rubber tires at low speeds, reducing efficiency gains.
• Mass: The electromagnets in many EMS and EDS designs require between 1 and 2 kilowatts per ton. The use of superconductor magnets can reduce the electromagnets' energy consumption. A 50-ton Transrapid maglev vehicle can lift an additional 20 tons, for a total of 70 tons, which consumes 70–140 kilowatts (94–188 hp). Most energy use for the TRI is for propulsion and overcoming air resistance at speeds over 100 miles per hour (160 km/h).
• Weight loading: High-speed rail requires more support and construction for its concentrated wheel loading. Maglev cars are lighter and distribute weight more evenly.
• Noise: Because the major source of noise of a maglev train comes from displaced air rather than from wheels touching rails, maglev trains produce less noise than a conventional train at equivalent speeds. However, the psychoacoustic profile of the maglev may reduce this benefit: a study concluded that maglev noise should be rated like road traffic, while conventional trains experience a 5–10 dB "bonus", as they are found less annoying at the same loudness level.
• Magnet reliability: Superconducting magnets are generally used to generate the powerful magnetic fields to levitate and propel the trains. These magnets must be kept below their critical temperatures (this ranges from 4.2 K to 77 K, depending on the material). New alloys and manufacturing techniques in superconductors and cooling systems have helped address this issue.
• Control systems: No signaling systems are needed for high-speed maglev, because such systems are computer-controlled. Human operators cannot react fast enough to manage high-speed trains. High-speed systems require dedicated rights-of-way and are usually elevated. Two maglev system microwave towers are in constant contact with trains. There is no need for train whistles or horns, either.
• Terrain: Maglevs can ascend higher grades, offering more routing flexibility and reduced tunneling.