Maglev

Maglev (derived from magnetic levitation) is a transport method that uses magnetic levitation to move vehicles without making contact with the ground. With maglev, a vehicle travels along a guideway using magnets to create both lift and propulsion, thereby reducing friction by a great extent and allowing very high speeds. In itself, maglev technology includes no moving parts.

Maglev trains move more smoothly and more quietly than wheeled mass transit systems. The power needed for levitation is typically not a large percentage of its overall energy consumption; most goes to overcome drag, as with other high-speed transport. Maglev trains hold the speed record for trains.

Compared to conventional trains, differences in construction affect the economics of maglev trains, making them much more efficient. For high-speed trains with wheels, wear and tear from friction from wheels on rails accelerates equipment wear and prevents high speeds. Conversely, maglev systems have been much more expensive to construct, offsetting lower maintenance costs.

Despite decades of research and development, maglev transport systems are in operation in just three countries (Japan, Korea and China). In April 2004, Shanghai's Transrapid system began commercial operations. In March 2005, Japan began operation of its relatively low-speed HSST "Linimo" line in time for the 2005 World Expo. In its first three months, the Linimo line carried over 10 million passengers. South Korea became the world's fourth country to succeed in implementing maglev technology with the Incheon Airport Maglev beginning regular operation on February 3, 2016. While the Transrapid in Shanghai was primarily based on german technology, China has started its own program for low speed maglev with the Changsha Maglev in operation in Changsha and the S1 Line in Beijing under construction. In Japan a new high speed maglev line, the Chuo Shinkansen is planned to become operational in 2027, with construction starting 2017.

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