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20 December 2009
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With the present situation regarding public
transport in many places, it is acknowledged that the private car is a must for
probably most families. However, the present mindset of buying the biggest and most
luxurious car, to impress the neighbours, is little short of irresponsible.
A small to medium-sized petrol car with catalytic converter is cheaper to
buy, to tax, to insure, to run, causes less pollution and is every bit as
comfortable for the length of average trips - and it is
still just as easy to be caught in a radar trap! As I said earlier, anything
over 2 litres for an ordinary 5-seater family car is wasteful and, if local
roads dictate that you must have 4-WD, there is still a choice of
good ones at this level. There is prestige to be gained by showing people
that you prefer an environmentally responsible vehicle, rather than a de-luxe
limousine or a sports car.
There are few electric cars available or
suitable. In any case, if there were a large fleet of them, they
would have to be charged from the electricity supply, which is generally not
dimensioned for the extra load, and which usually burns fossil fuels less
efficiently than a conventional car.
They are not environmentally acceptable. Wide-scale trials in California
have shown that electric cars are not acceptable to the public either;
owners of them rarely renew their vehicles with another electric vehicle and
many stop using them within a matter of months, they are so inconvenient.
A new type of electric car is in development in the USA, in which the
battery is complemented by a small petrol-electric generator. Note that
this is not a hybrid car, because the only drive to the wheels is the
electric motor. The battery, whether charged from the grid or the
generator, has an autonomy of the order of 50-80 km, so this is probably
good for many commuters, with the advantage over "conventional" electric
cars that, as long as there is some petrol in the tank, the driver will
never be stuck with a flat battery. Initial price estimates indicate
that it may be quite costly for a car of its dimensions and performance,
mainly because of an expensive Li-ion battery with such a respectable
autonomy. It remains to be seen what the fuel consumption will be as a
non-plug-in car, compared with hybrids.
There are several models, from small coupés to medium
saloon cars to SUVs and people carriers, made in mass production with typical
consumptions of less than half that of a comparable
conventional car. Most of them come from Japan but production is also
starting in the USA. They have been in production for some years and the
technology has been mastered. The American motoring magazine, Motor Trend,
mostly directed towards cutting-edge enthusiasts' sports car, has named a
hybrid car its
Car of the Year 2004; this link is well worth reading, if only to
show the direction that the car is heading. The car in question in this link
has a town consumption of only 3.96 l/100 km! This means that its 45 litre
tank of lead-free petrol will take you an astounding 1,100 km before you
have to refill - all around Nicosia! Because the widespread adoption of
such cars would help solve various countries' commitments towards reducing
carbon dioxide emissions, there are various subsidies or tax relief
available for owners. In Cyprus, the subsidy for such cars is nearly €1,200.
The two major contenders, at this time, are the Honda
Civic Hybrid and the Toyota Prius, each of which has a different basic
concept. This makes the former better for the person having to travel
much along the motorways, while the Prius is better for town driving. My
experience with a hybrid is given in detail at
this site.
Theoretically, the "chip-oil" car could be anywhere. This is a standard car with a modified diesel engine designed to
use vegetable oils as fuel. The used oil is collected from crisp factories,
hotels, restaurants and other sources. It is carefully filtered and refined
and then thinned down with a small quantity of kerosene. Of course, it emits
just as much pollution as any other diesel car; the difference is that 90
per cent of the fuel is from non-fossil fuel sources and the carbon dioxide
is therefore renewable to the same extent. It is uncertain whether the
collection, treatment and distribution of used vegetable oilwould
be commercially viable, because the quantities of raw materials is
relatively small and would suffice only for a fraction of the cars on the
road. However, cars with the modified diesel engines
can run equally well on conventional diesel oil, so that the vegetable oil
could be used when it was available.
Other biofuel oils can be used in such cars, such as palm, hemp,
colza (rape, canola), sunflower and even olive. However, production in
most countries is insufficient to provide sufficient oil without
compromising food availability. Most vegetable oils solidify at
temperatures around freezing. This makes their use impossible in cold
climates, unless mixed with large proportions of conventional diesel
fuel or unless they are cracked into lighter fractions.
Nobody can predict the car of the future. The
hydrogen-powered fuel-cell car is being much hyped as one possibility,
although it is unlikely to be in full production in less than 12 or 15 years
from now. Although the protagonists claim that this is the way that private
cars will go, there are still many unanswered questions. Some of these
issues have been evoked in the essay on
Hydrogen.
It is shown that it would seem very doubtful whether this type of vehicle
would work unless the people accepts the notion of
nuclear power stations to provide the massive energy for electrolysis. However, there are severe doubts as to whether the
hydrogen fuel-cell cars will ever become a mainstream solution, because:
-
the fuel cells are expensive and their
longevity has not been proven in a transport environment
-
the hydrogen has to be of very high purity
to avoid "poisoning" the fuel cells; the cost of purifying the hydrogen
will be at least as high as producing it in the first place
-
current fuel cells require platinum in
their construction; there is insufficient platinum in the world to
supply more than a fraction of the number of cars and, if they did
become popular, the price would rocket as platinum reserves became
depleted
-
it is uncertain whether the 5 to 10 minute
interval between starting the car from cold and driving off would be
acceptable to the consumer
-
because fuel cells work at a much lower temperature than internal
combustion engines, the exhaust water vapour may condense and freeze in
cold weather.
-
the overall efficiency ("well-to-wheels") from the energy
required to make the hydrogen to the propulsive energy available at the
car's wheels is no higher than with a conventional car and lower
than a hybrid petrol-electric car. We need higher efficiencies for our
future transport.
-
it is uncertain whether the price of such a
car could be brought down to acceptable levels (the experimental cars
that are running in the USA and Europe cost over $1 million each, at the
moment)
In the shorter term, it would certainly be the
hybrid car that would offer the best solution. By 2010/2015, there will
probably be tens of models with very advanced technology available on the
market at attractive prices.
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