death, because they breathe harmful
substances, making air pollution one of the
the world’s biggest environmental problems.
Smog is big trouble in China. Sixteen of
the world’s most polluted cities are located in
the world’s most populous nation, which
itself is home to a total of 1.4 billion people.
In Beijing, pollution exceeds international
threshold values of unhealthy air more than
half of the year. On the worst days, the air is
worse than chain smoking.
China’s extremely unhealthy air is due to
a combination of emissions from different
sources. From power station chimneys,
carbon dioxide is emitted, the exhaust pipes
of cars fill the air with nitrogen dioxide, and
ammonia vapour the result of the use of
artificial fertilisers. Several of the gases also
combine in the air, producing even more
toxins. In late 2016, a US-Chinese study
showed that cities with both heavy industry
and heavy traffic are tormented by extramany extremely harmful sulphate
compounds, which form based on sulphur
dioxide, when large quantities of nitrogen
dioxide are present.TINY PARTICLES – MAJOR PROBLEMS
But in recent years, the toxic gases in the
atmosphere have been overshadowed by a
much more worrying type of pollution:
microscopic particles which are so small that
they can enter deep into the lungs, passingHYDROGEN ELECTRICITY
Pug-in electric cars are more common than hy-
drogen-powered models, which need new pump-
ing infrastructure to supply us with fuel.Battery-electric today,
hydrogen fuel cell laterREACH
Modern hydrogen-powered cars
drive about 500 km on a tank of
fuel or about the same as many small
ordinary cars.REACH
Cheaper models can manage about
200 km per charge, while luxury
EVs can drive over 550 km.REFUELLING
Hydrogen stations are rare. The
refuelling of a hydrogen-powered
car typically takes the same time as an
ordinary car.REFUELLING
Using special fast chargers, half a
charge can be completed in a few
minutes. A full charge can take up to
two hours, or even overnight.ENVIRONMENT
The exhaust is pure water, but
hydrogen production takes place by
methane fission in natural gas. The
residual product is CO 2.ENVIRONMENT
Electric cars have no exhaust, but
even today much of their power
comes from coal-fired electricity.VS
Soon
SMOG REDUCTION:
100 %
In Mexico City and Beijing, the
authorities regulate the right to
drive in the city based on license
plates. If the last number of its
license plate is even, a car is
allowed into the city centre on
even dates – and vice versa for
license plates ending in odd
numbers. But so far, the rule has
just led to families buy two cars
with different license plates.LICENSE PLATE RULE
BACKFIRED
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