Sub-100g/km carbon dioxide emissions is the new black and, as a French manufacturer, Peugeot likes to stay on top of the latest trends, writes Richard M Hammond.

Sub-100g/km carbon dioxide emissions is the new black and, as a French manufacturer, Peugeot likes to stay on top of the latest trends, writes Richard M Hammond. As a result, the latest incarnation of the 207 hatchback emits a mere 99g/km of CO2.

The current line-up hyper-efficient sub-100g/km CO2 emitting B-segment models from differing car-makers all have a lot in common, not least that they all started from an advantageous position in terms of an already economical engine.

Peugeot's 207 Economique makes good use of the range's 1.6-litre turbocharged diesel unit. In non-intercooled form the HDi engine produces 90bhp, but it's the 161lb/ft of torque that is of most use when it comes to wringing out as much economy as possible.

It's not strictly the same engine as on the standard 90bhp diesel cars, however. The Economique's unit uses an exhaust gas recirculation heat exchanger that cools the re-injected gases and has a remapped electronic control unit to minimise fuel consumption.

Drivers will notice the effect of these additions in terms of their fuel bills, but behind the wheel it's the gearbox's increased final drive ratio that will be most noticeable.

Rather than adjust individual gear ratios within the five-speed gearbox Peugeot has opted to raise the transmission's final drive ratio, meaning all of the gears are longer than in the standard 207.

This is where the high-torque output of the diesel unit proves its worth, effortlessly dealing with the long gears and allowing the 207 Economique to get up to speed without needing to be revved hard. At motorway cruising speed the revs stay low, meaning the 207 Economique makes a surprisingly refined long-distance cruiser.

In town, the long first second and third gears take a little more getting used to - particularly getting into the habit of holding first longer and not being able to crawl so readily in second. Despite this, the 207 loses none of its city car appeal and less frequent gear changes make for smoother progress in stop-start traffic.

Engine and transmission adjustments are not the only changes helping the 207 Economique towards its 99g/km performance. As is the norm for eco-friendly models, the bodywork has come in for some fine tuning, too. The standard model's drag coefficient of 0.30 has been reduced to 0.274 by fitting a modified front bumper and sidesills, smoothing out the underside with an under-tray round the fuel tank, a discreet but effective rear spoiler and ride height dropped by 5mm.

Already a distinctive and fashionable car, the changes have done little to affect the 207's kerb appeal. LED-effect rear lights are particularly contemporary and although alloy wheels are not an option - the model is shod with steel wheels and special aero hub caps instead - Peugeot is adept at making reasonably basic specification look stylish and feel very comfortable.

There are actually two specifications of the 99g/km 207 available, with the more expensive Economique+ boasting air-conditioning, a trip computer and electric, heated door mirrors. But despite its humble specification the Economique trim level doesn't disappoint in the comfort stakes.

A neat interior shows the hallmarks of having been designed with style and ergonomics in mind and the shapely seats are supportive and comfortable in the front and rear. Available in three or five-door form, the three-door actually performs quite well when it comes to access. There's space in the back for two adults and the three belts mean a trio of smaller frames can be carried. Bootspace is more than acceptable for a B-segment hatchback, too.

Annual road tax-free status and impressive real-world fuel economy are clearly the big attractions, but the fact the 207 Economique delivers them alongside the usual mixture of town-friendly dimensions, easy driving experience and family-friendly packaging makes the already popular 207 even more enticing. The Economique is missing some mod-cons, but the quality of what is present help make up for it.

PEUGEOT 207 ECONOMIQUE

Model: �13,495 on the road

Engine: 1.6-litre, 90bhp turbo diesel

Transmission: Five-speed manual, driving the front wheels

Performance: 0-62mph, 11.7 seconds; top speed, 115mph

CO2 emissions: 99g/km.

Economy: 74.3mpg combined