The domestic car is probably one of the easiest
offenders to tackle, so I'm going to start there.
First, nitrogen dioxide, which when released into
the atmosphere, becomes nitric acid, is a simple
enough one to cure. Nitrogen doesn't just spring
into existance, after all. If it doesn't enter
the system, it won't leave the system. But how to
stop it from entering the system in the first
One way (and it's not necessarily the best or the
most efficient for this purpose) is to simply have
a charged mesh at the front of your air intake.
The electrons around oxygen are much easier to
displace than those around nitrogen, leaving the
oxygen pairs charged and the nitrogen pairs
Then, place a junction in the air intake, with one
of the paths having a charged plate next to it.
The charged air molecules (including the oxygen)
will turn down that path, leaving the nitrogen and
other uncharged particles to go the other way.
This would greatly enrich the oxygen to the engine
and almost eliminate the nitrogen content, thereby
eliminating any nitrogen-based waste products.
Then, there's the waste heat the engine is producing.
That, in itself, isn't a problem. The problem is
that that is energy you can't use, and therefore
you end up burning additional fuel to make up for
Heat is a real problem, since it's a natural
result of any exothermic reaction. (That's why it
is -called- an exothermic reaction! :) However,
both Classical Physics and Quantum Physics come to
our rescue. (Phew!) In classical physics, you must
always satisfy the conservation of momentum AND
the conservation of energy, where momentum (M) and
kinetic energy (ke) are defined as: M = m.v, ke =
m.v^2 (where m = mass and v = velocity).
Because momentum is a function of velocity, whereas
kinetic energy is a function of velocity squared,
not all values are going to work. Some situations
are simply impossible. All you have to do is make
the engine a system where the "surplus" components
needed to satisfy both equations are nearly zero.
The better you can do that, the less waste heat
you will produce.
Now, we get into the quantum physics. These systems
are not continuous. They operate in fixed-size
steps, called quanta (greek for 'enough'). The
energies of any given region will be quantized and
can never have any values outside of that. To
ensure that we get the results we want, rather
than some alternative solution to the classical
equations, we must ensure that the solution we
want satisfies the conditions imposed by quantum
mechanics, and that ALL alternative solutions to
the classical equations would violate these
Now, we move from the engine to the exhaust
system, where turbulence and other chaotic effects
reside. Grooved surfaces break up turbulence, and
may improve the flow of air.
On the theme of air-flow, we now go onto
aerodynamics. Near-vertical front & back, uneven
underbody and sod all stream-lining. A brick would
be only marginally worse. You need to push the air
away without transferring 90% of your engine's
output to it. If you have the car's sides
deformable, and push the air left or right, you
can meet all those requirements and improve
handling AND performance, at the same time.
("Classical" aerodynamic aids rely on "ground
effect" - read: sucking the car to the road. But
this seriously throws all efficiency to the wind.
On the other hand, using the air to "pull" a car
to the left or right would not reduce efficiency,
whilst still assisting the car in turning.)
Last, but by no means least, I'll tackle gearing.
An engine is tuned to produce optimal performance
within a particular rev band. (In racing, this band
is extremely narrow.) The driver then uses the
gears to keep the car, as far as possible, within
that band and (ideally) at the point of peak
performance. The more gears you have, and the
closer they are together, the better you can do
this, and the better the millage. (This is why
manual cars, which have 4 or 5 gears, all do better
than automatics, where 3 gears is normal. You just
can't keep the car at it's optimal point, on only
However, even 5 gears is a very small number. What
you -really- need is a continuous gear ratio, with
the car's engine at a fixed number of revs. Then
you can tune the car to that spike, and you are
always going to get the best out of the engine.
How to do that, though? Simple. The gear ratio is
simply the ratio of the radii of the two wheels
used for the gears. If one of those wheels is
expanding/contracting, depending on the speed of
its rotation, you'd have continuous gears. An
overly-simplistic way to do this would be to have
one "wheel" simply be wheel segments that are
pulled together by some sort of spring. Inertia
will force the segments apart, when you accelerate,
and the restoring force of the spring would force
the segments back closed, when you brake.
This is by no means a "perfect" car, and it is
doubtful it would even work, as written above. But
these ideas demonstrate that there are ways to
improve the design of vehicles, at negligable cost
or effort, in a way that would improve efficiency
and reduce pollution.
At this point, I'd like to shut up and encourage
others to contribute their own thoughts on how to
improve vehicle design. (Comments on the above
ideas are also welcome.)