Magnet Milestones: Maglev Trains
Maglev trains are making history right now
By Amy Mast
Trains, once the way to move
people and cargo long distances
around the United States, are
enjoying a comeback. This year alone, the
U.S. government has promised $13 billion
to fund various high-speed rail projects.
Why? Trains are more energy-efficient
than air travel, are safer than commuting
in a car, and once they're up and running,
trains are one of the cheapest forms of
public transport around.
Maglev train.
One much-discussed type of train is the
maglev train, which uses magnets to
glide on a cushion of air at amazingly high
speeds – typically in the 150-250 mile per
hour range. The cushion of air means far
less friction and far more energy efficiency
than traditional rail trains.
This might sound like something from
a science fiction movie, but in fact, the
first-ever patent for a variation on a high-speed
train was granted in 1902. Similar
patents followed in ensuing years, but
engineers didn't hit on a truly workable
version of the train until the early
1960s, when a design for an engine was
developed that wouldn't require contact
with the tracks. This type of engine is
called a linear motor, and it's a concept
that's still being fine-tuned today.
Maglev trains are powered in a number
of ways, but as the name implies, all
use some form of magnets – whether
electromagnets or permanent magnets.
Superconducting maglev trains are in
the development stage. These trains
travel faster and are less expensive
to operate in the long run because
they employ superconductors,
materials that conduct electricity
without any friction, and therefore
use very little electricity.
Did You Know? The fastest high-speed train in the
world is in Shanghai. Though
the track is only about 18 miles
long, its top tested speed is 311 miles
per hour. Train operators call the
train's runs "flights."
The biggest obstacle to maglev
development is cost. Since these
superfast trains can't run on
traditional tracks, they require
the construction of all-new
infrastructure from scratch – a
daunting prospect in an uncertain
global economy. That said,
research on and proposals for new
projects pop up as fast as other
proposals are scrapped, primed
for the time when the funding
available matches the promise of
this potentially game-changing
technology.
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