Tokyo Motor Show - Mercedes-Benz

What will make it to the showrooms?
A method of cleaning sooty particulates of nitrous oxide (NOx) out of the exhaust fumes of diesel cars.

After the exhaust gases have passed through the car’ catalytic converter they are injected with a substance called Adblue – a chemical created from urea – which removes 80% of the NOx they contain.

Mercedes has tested the idea on the new S-Class and claims it makes it the cleanest diesel engine in the world, capable of meeting all present and future emissions legislation, including the tough new standards to be imposed by Japan and California.

Adblue is already available in 700 service stations in Europe and is being used daily by 5500 trucks. Mercedes plans to have the system in operation in the S-Class next year.

It is also looking at combining its V6 turbodiesel engine with a small electric motor to make the S-Class even more fuel-efficient and clean.

The motor is housed in the automatic transmission case and includes a stop-start mechanism to switch the engine off when the car is stationary and restart it at a touch of the accelerator.

Mercedes claims the diesel-electric hybrid S-Class would be the most economical luxury car in the world, capable of around 37mpg. Performance does not suffer, either: the company talks of a 7.2sec 0-62mph time and a 155mph top speed.

What’s the best bit?

It’s still an S-Class.

And the worst?
Adblue is currently scarce, if there are only 700 European service stations selling it.

Any other developments?
Mercedes is also working on fuel cell cars and revealed its latest prototype, the F600 HyGenius, at Tokyo.

It is said to be 30% more powerful than previous fuel cell cars (Mercedes quotes 115bhp and 235lb ft of pulling power), 60% more energy efficient and to have a hydrogen cell 40% smaller than the norm.

‘It competes with conventional engines on acceleration, speed and the range it can cover on a tank of fuel and speeds development of fuel cells towards market introduction,’ Mercedes says.

Any gossip?
The HyGenius also has some clever safety features – front seats that can easily be turned into supports for rear-facing child seats, and cameras in the door mirrors that eliminate blind spots – and neat touches such as cupholders that can keep drinks warm or cold.

It is also said to produce enough electric power to supply several homes.