Renault is to debut its lowest CO2 emitting production car today at the Brussels Auto Show. The new 98 gram CO2 per kilometre Clio dCi 86 Renault eco² achieves a 17g per km reduction in CO2 emissions (15% overall) compared to the current engine.

Renault say that the efficiency gains have been realised through a series of aerodynamic, engine and
tyre improvements. Combined fuel economy on the variant is raised to 76.3 mpg (an increase of 12.1 mpg) and drag co-efficient reduced from 0.725 to 0.69 CdA.

Renault claims the car has a theoretical range of 923 miles between fill-ups.

The car will cost the same as the current 115g/km variant and will be available to order in France from 9th February and later this year in UK.

Renault says it is committed to attaining a leadership position in CO2 emissions by 2015, not only by cutting the CO2 emissions of its diesel and petrol ranges, but also through the development of its electric vehicle range.

Renaut's engineers focused particularly on fine-tuning the dCi 86 powerplant in order to achieve the greatest possible improvement in CO2 emissions levels, without unduly affecting performance.

This included:

  • Longer gearing across all the transmission ratios: the torque and the flexibility of the dCi 86 allow this to be achieved without any significant impact on performance;
  • Reduction of frictional losses in the engine and gearbox with the introduction of low-viscosity lubricants;
  • Dedicated engine mapping focused on reducing fuel consumption and CO2 emissions

Improvements to aerodynamics included:

  • Flexible lip under front bumper extended by 15mm;
  • Front wheel arch liner extension flaps;
  • Specific underbody enclosure for rear axle

Reduced rolling resistance measures included the fitment of Michelin 185x60 R15 low energy consumption tyres.

Taken together, these changes bring about a 5 per cent improvement in CdA, taking it from 0.725 to 0.69 and directly benefiting the vehicle's CO2 emissions.