Volvo C30 news - Volvo gives C30 the slip - 2007

You probably haven't seen many Volvo C30s out on the road yet, but that could change - in central London at least - as the curvy-backed hatch has become the latest car to sneak under the 120g/km emissions watershed thanks to a bunch of minor modifications.

That CO2 figure looks like becoming the manufacturer's holy grail, and this green new C30 - called the Efficiency, predictably - will join the BMW 120d, Mini Cooper D and a handful of other candidates to roam freely around the City o' London next year.

Volvo has greenified the C30 by following the VW BlueMotion template: shunning hybrid drivetrains and regenerative braking in favour of slippier aerodynamics, longer gearing and low friction tyres.

The C30 is also gets Volvo's new Powershift diesel transmission, a dual-clutch automatic gearbox similar to VAG's DSG effort. Coupled to the aero modifications - which include more streamlined 16-inch alloys, impressively - this helps the C30 Efficiency achieve 62.8mpg (a jump of 5mpg over the stock 1.6-litre C30 turbodiesel) and sneak below 120g/km of CO2.

No, it's not the most sexy eco-technology around, but this BlueMotioning (we'll let VW have it, they got there first) approach is all good news.

We'd expect more manufacturers to follow suit, but sadly we can't see a streamlined, skinny-tyred Hummer on the horizon any time soon. Pity.