“Hang on! You haven’t mentioned magnetic levitation”

The German company, Transrapid, which made the maglev train for Shang-
hai, China (figure 20.33), says: “The Transrapid Superspeed Maglev System
is unrivaled when it comes to noise emission, energy consumption,
and land use. The innovative non-contact transportation system provides
mobility without the environment falling by the wayside.”

Magnetic levitation is one of many technologies that gets hyped up
when people are discussing energy issues. In energy-consumption terms,
the comparison with other fast trains is actually not as flattering as the
hype suggests. The Transrapid site compares the Transrapid with the Inter-
CityExpress (ICE), a high-speed electric train.

Fast trains compared
at 200 km/h (125mph)
Transrapid 2.2 kWh per 100 seat-km
ICE 2.9 kWh per 100 seat-km

The main reasons why maglev is slightly better than the ICE are: the
magnetic propulsion motor has high efficiency; the train itself has low
mass, because most of the propulsion system is in the track, rather than
the train; and more passengers are inside the train because space is not
needed for motors. Oh, and perhaps because the data are from the maglev
company’s website, so are bound to make the maglev look better!

Incidentally, people who have seen the Transrapid train in Shanghai tell
me that at full speed it is “about as quiet as a jet aircraft.”

Notes and further reading

page no.

119 A widely quoted statistic says “Only 1% of fuel energy in a car goes into
moving the driver.”
In fact the percentage in this myth varies in size as it
commutes around the urban community. Some people say “5% of the energy
goes into moving the driver.” Others say “A mere three tenths of 1 percent of
fuel energy goes into moving the driver.” [4qgg8q] My take, by the way, is
that none of these statistics is correct or helpful.

The bicycle’s performance is about the same as the eco-car’s. Cycling on
a single-person bike costs about 1.6 kWh per 100 km, assuming a speed of
20 km/h. For details and references, see Chapter A, p262.

The 8-carriage stopping train from Cambridge to London (figure 20.4) weighs
275 tonnes, and can carry 584 passengers seated. Its maximum speed is
100mph (161 km/h), and the power output is 1.5 MW. If all the seats are occupied,
this train at top speed consumes at most 1.6 kWh per 100 passenger-km.

Figure 20.33. A maglev train at Pudong International Airport, Shanghai.

“driving without wheels;
flying without wings.”

Photo by Alex Needham.
Figure 20.34. Nine out of ten vehicles in London are G-Wizes. (And 95% of statistics are made up.)