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FREQUENTLY ASKED QUESTIONS AND ANSWERS
ABOUT MAGLEV
- How much will it cost to travel by
Maglev compared to airplanes? Will it be faster or slower,
more comfortable?

- Why is Maglev better than the High-Speed
Trains already operating in Europe and Japan?

- How will Maglev change my life, other
than making it easier to take trips?

- Why are superconducting magnets used
in the Japanese and M-2000 Maglev systems? What are the
advantages and disadvantages of superconducting magnets?

- What is a superconducting magnet?
How is it different from ordinary magnets?

- Are superconducting magnets really
dependable? Will it be safe to travel by Maglev?

- What happens if the electric power
is cut off to a Maglev guideway? Will the vehicles on it
crash?
- Are there any health or environmental
hazards from the magnetic fields of a Maglev vehicle?
 
- Why don't we already have Maglev
systems? If they are as good as you say, why aren't they
being built?

- You state that Maglev vehicles can
deliver trailers and freight containers over long distances
at high speed and low cost. What about personal autos?
Q. How much will it cost to travel
by Maglev compared to airplanes? Will it be faster or slower,
more comfortable?
A. The average cost for air travel is about 13 cents
per passenger mile. This includes labor, airplanes, fuel,
and other costs, and corresponds to a ticket price of about
$600 round trip, for a coast-to-coast flight. Some tickets
cost less, some more, for a particular flight, depending on
the discount offer, date of purchase, age, and so on. The
13 cents per passenger mile does not include government subsidies
for airports, highway access, FAA operations, etc.
M-2000 Maglev operational costs for vehicles, energy, and
labor total about 4 cents per passenger mile, not including
the amortization cost for the guideway. Projecting guideway
amortization cost is difficult since it depends on ridership
and whether the guideway carries freight as well as passengers.
For a M-2000 guideway cost of 10 million dollars per 2-way
mile, that carries only passengers, amortization cost is about
10 cents per passenger mile, assuming a 30-year payback period
and 10,000 passengers daily. If the guideway carries 1000
trailers daily and allocates 3 cents per ton mile (30 tons
per trailer} of revenue to guideway amortization, the passenger
share for guideway amortization is zero cents per passenger
mile. Total cost for passengers is then only 4 cents per passenger
mile, about 1/3 of that for air travel. If M-2000 guideways
carry both passengers and truck type freight, Maglev will
be much cheaper than air travel.
Although jet aircraft speed is greater than Maglev (500 mph
compared to 300 mph) the actual trip time will be much less
for Maglev. First, access to Maglev stations will be much
easier and faster than airports. With the M-2000 National
Maglev Network, over 70% of the population will live within
15 miles of a Maglev station, which they could reach in a
few minutes. Second, the departure frequency of Maglev vehicles
will be much greater than for aircraft. Most airports have
only a few flights daily to a given destination: Maglev stations
will typically have dozens. Third, Maglev schedules will not
be upset by bad weather or congestion, which is often the
case for air travel.
Finally, because Maglev vehicles are much cheaper than airliners
-a few million dollars per vehicle, compared to a 100 million
dollars or more for an airliner - and because their operating
cost is very low, Maglev travel will be much more comfortable
than air travel. There is no need to pack riders in like sardines
to save money -passengers will travel in first class style,
for lower cost than economy air. Moreover, the vibration and
noise experienced on airliners are completely absent on Maglev
vehicles.
Q. Why is Maglev better than the
High-Speed Trains already operating in Europe and Japan?
A. Maglev is better than high-speed trains for many
reasons. First, rather than the point-to-point service between
city centers characteristic of high speed rail, Maglev will
have many more stations, distributed so that people have easy
and fast access to the Maglev Network. Second, individual
Maglev vehicles will hold 100 people at most, compared to
the 500 to 1000 people on a high-speed train. This enables
more frequent and convenient service. Third, Maglev vehicles
travel at 300 mph, compared to 180 mph for high-speed trains.
The faster Maglev vehicles, plus their ability to accelerate
and decelerate much more quickly, cut the travel time for
Maglev by at least a factor of 2, as compared to high speed
rail. Fourth, the Maglev noise is much less than steel wheels
on rail. Finally, Maglev vehicles travel on elevated guideways,
something that the much heavier trains cannot do. Elevated
Maglev guideways enhance safety and reduce environmental impact,
compared to an on-grade rail track.
Q. How will Maglev change my life,
other than making it easier to take trips?
A. Maglev will dramatically change the way people
live in the 21st Century, with effects far beyond those associated
with personal trips. First, and very important, with Maglev
people will live much farther from their work place and from
city centers, while still being able to travel to them in
a short time. Spreading population over a much larger area
than is possible with present transport systems will greatly
reduce the cost of owning a home, and allow people to enjoy
nature much more.
Second, sending trailer trucks by Maglev instead of on highways
will cut the costs of goods, increase highway safety, reduce
congestion and delays, and make the highways last much longer.
Third, Maglev will greatly reduce pollution, extend oil resources
and help keep oil and gas prices reasonable, and lessen the
rate at which carbon dioxide is released into the atmosphere.
This will help slow global warming.
Fourth, Maglev because of its potential for greatly reducing
the cost of launching payloads into orbit will open up space
to much greater usage, colonization, and eventually tourism.
Q. Why are superconducting magnets
used in the Japanese and M-2000 Maglev systems? What are the
advantages and disadvantages of superconducting magnets?
A. Superconducting magnets are used in the M-2000
and Japanese Maglev Systems for the following reasons:
- Superconducting magnets enable Maglev vehicles to operate
with much greater clearances above the guideway, than are
possible with room temperature magnets. With superconducting
magnets, the gap between the Maglev vehicle and the guideway
can be 6 inches. With room temperature electromagnets or
permanent magnets, the gap is only about 3/8 of an inch.
Large gaps improve safety, allow greater construction tolerances,
decrease construction costs, and reduce sensitivity to ground
settling and earthquakes.
- Superconducting magnets enable the levitated vehicle to
be inherently and passively strongly stable against external
forces (winds, grades, curves, etc.) that act to displace
the vehicle from its normal suspension point. Attractive
force suspensions based on room temperature electromagnets
are inherently unstable, and require constant, fast response
servo control of the magnet current to operate safely.
- Superconducting magnets let Maglev vehicles levitate much
heavier loads than are possible with room temperature electromagnets
or permanent magnets. Heavier load capacity lets Maglev
vehicles carry freight, water, mining ores, etc., to generate
large revenues.
- Superconducting magnets have much lower power requirements
than conventional room temperature electromagnets.
The only disadvantage of superconducting magnets is their
need for refrigeration. However, the power for the refrigerator
is small compared to the power to overcome air drag on the
vehicle. Accordingly, operating cost for superconductors is
a minor perturbation.
The superconducting magnets on Maglev vehicles are not complicated
to construct or operate. Thousands of superconducting magnets
now operate routinely and reliably around the world in MRI
devices, high-energy accelerators, and other applications.
Q. What is a superconducting magnet?
How is it different from ordinary magnets?
A. The main difference between superconducting magnets
and conventional room temperature electromagnets, is that
they use low temperature, zero electrical resistance conductor
wire in the magnet winding, instead of room temperature, non-zero
electrical resistance conductor. Conventional electromagnets
use aluminum or copper conductor, while superconductor magnets
use niobium-titanium-copper wire (or other superconductor,
depending on application). Also, conventional electromagnets
often use iron cores to reduce the current and I2R losses
in the conductor winding.
Because superconductors have no electrical resistance, very
high currents and current densities are practical, resulting
in much more powerful electromagnets than are possible with
room temperature conductors. While room temperature permanent
magnets have no current windings or I2R losses, their inherent
physical characteristics limit their magnetic field capabilities
to much less than those of superconducting magnets.
Superconducting magnets require good thermal insulation to
keep the superconductors cold. They also have to be cooled
with helium (for low temperature superconductors) or nitrogen
(for high temperature super conductors) compared to conventional
electromagnets which are cooled by ordinary water.
Q. Are superconducting magnets
really dependable? Will it be safe to travel by Maglev?
A. Superconducting magnets are highly reliable. High-energy
accelerators routinely operate with many hundreds of superconducting
magnets positioned along the path followed by particles that
travel in precise orbits along miles of evacuated tubes. If
only one of these many hundred magnets failed, it would shut
down the accelerator for a long period while the magnet was
repaired or replaced. Such a situation could not be tolerated,
and in fact, does not occur in practice. In the proposed superconducting
super collider (SSC), for example, over 10,000 superconducting
magnets would have been positioned along the 76-kilometer
circumference of the SSC. Failure of one of these magnets
would have shut down the SSC.
The M-2000 Maglev vehicles are designed with multiple (typically
16) superconducting magnets that operate separately and independently
of each other. The M-2000 vehicle will remain levitated and
operate safely even if several of its magnets were to fail.
Because the failure rate of superconducting magnets is very
low, the probability of two magnets failing in a period of
few minutes, the time needed to reach a stopping point, would
be less than once in a million years of operation.
Such a failure rate is much smaller than the engine failure
rate in jet aircraft. Furthermore, the Maglev vehicle would
continue to operate, while the jet aircraft would not. In
fact, it would take the simultaneous failure of at least 6
independent magnets to compromise levitation capability -a
probability that is infinitesimally small compared to other
modes of transport.
Q. What happens if the electric
power is cut off to a Maglev guideway? Will the vehicles on
it crash?
A. The M-2000 vehicles are automatically and passively
stably levitated as long as they move along the guideway.
The electric power fed to the guideway magnetically propels
the M-2000 vehicles and maintains their speed. If the guideway
power were cut off, the vehicles would coast for several miles,
gradually slowing down due to air drag. When they reach 30
mph, they settle down on auxiliary wheels and brake to a stop
on the guideway. When power is restored to the guideway propulsion
windings, the vehicles can magnetically accelerate back up
to their cruising speed.
Because the vehicles are automatically levitated and stabilized
for speeds greater than 30 mph, there is no chance of a crash
if guideway power is cut off.
Q. Are there any health or environmental
hazards from the magnetic fields of a Maglev vehicle?
A. There are no health and environmental hazards from
the magnetic fields around the M-2000 Maglev vehicle. The
magnetic fringe fields from the quadrupole magnets on the
M-2000 vehicles drop off much faster with distance than do
the fringe fields from dipole magnets. This rapid decrease
in fringe fields allows the magnetic fields in the passenger
compartment to be at Earth ambient level, ~ 0.5 Gauss. All
humans live constantly in Earth's magnetic field and are adapted
to it. They will experience no difference in field strength
when they ride in a M-2000 Maglev vehicle.
In fact, people presently experience stronger magnetic fields
than the Earth ambient value when they ride subways and electrified
trains, when they operate electrically powered equipment in
the home or when they walk down city streets. The magnetic
fields in M-2000 vehicles will be lower than in the above
examples.
Q. Why don't we already have Maglev
systems? If they are as good as you say, why aren't they being
built?
A. There is a tremendous investment, both in money
and human experience, in our present modes of auto, truck,
air, and rail transport. The US spends almost a trillion dollars
annually on these transport systems. Until recently, they
have functioned adequately.
Moving into a new transport mode like Maglev is difficult
and takes time, because of the large capital investments required,
and the need for people to acquire new job skills and change
their ridership habits. Such a shift requires demonstration
Maglev systems to convince the public that Maglev is real.
Such demonstrations are now at hand. Moreover, the increased
congestion, delays, and costs of transport on the nation's
highways and airways will help speed the transition to Maglev.
Q. You state that Maglev vehicles
can deliver trailers and freight containers over long distances
at high speed and low cost. What about personal autos?
A. It appears practical to transport autos by Maglev
over long distances. Such capability would be attractive for
vacationers, since it would be much faster and more comfortable
than driving hundreds of miles. To transport an auto from
New York to Chicago by Maglev, a distance of 800 miles, would
cost about 100 dollars.
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