Renault Introduces Logan Renault Eco2 Concept at Challenge Bibendum; Taking a Production Car from 120g CO2/km to 97g
|Some of the elements and attributes contributing to the enhanced fuel economy of the Logan Renault eco2 concept. Click to enlarge. Illustration: Hubert Vincent|
Renault is introducing the Logan Renault eco2 concept, which will contest the 2007 Michelin-organized Challenge Bibendum in Shanghai, China running from 14-17 November.
In May, Renault introduced the Renault eco2 appelation for its most fuel-efficient and “ecological” products. Renault eco2 vehicles meet three global standards: they are produced in an ISO-14001-certified plant, their CO2 emissions do not exceed 140 g/km (or are biofuel-compatible) and, in addition to being 95% reusable at the end of their life, at least 5% of the plastics they contain have been recycled. (Earlier post.)
The Logan Renault eco2 Concept was manufactured at the Pitesti plant in Romania, which has been ISO 14001-certified since 2005, while the finished vehicle contains 8.3% of recycled plastics and is 95%-reusable by weight. The vehicle has a low CO2 emissions rating of 97 g/km.
Powered by a 1.5 dCi (63kW/85hp) engine which runs on B30 biofue1, Logan Renault eco2 Concept incorporates a variety of technical enhancements and innovations, all of which are paths for future vehicle development at Renault.
The powertrain is based on the 1.5 dCi (85hp) engine launched at the end of 2007 and homologated at 120g CO2/km. The final drive ratio has been lengthened 8% to reduce fuel consumption while ensuring a level of mid-range acceleration that is suitable for ordinary use. This enhancement enabled a saving of 4g of CO2/km.
Renault also re-calibrated the injection system by introducing seven-hole nozzles (instead of five as is the case with production models) and widening the piston bowl for enhanced fuel spray and combustion. This modification produced a saving of 5g of CO2/km.
Finally, by optimizing the play between certain moving parts and using low-viscosity lubricants (5W20 plus additives instead of the standard 5W30), Renault reduced internal engine friction. The gear oil is also less viscous. This work helped cut CO2 emissions by a further 2g/km.
Analysis of the most cost-effective solutions enabled Renault to identify six points which, together, produced significant aerodynamic gains.
A flexible splitter under the front bumper to reduce underbody turbulence combined with a spare-wheel fairing to optimize the flow of air underneath the car.
The front air intakes were modified to reduce the drag caused by air-cooling airflow.
Wheel fairings to reduce lateral turbulence.
A rear lip spoiler to reduce the vehicle’s overall drag performance.
VORTEX generators (small, drag-reducing, roof-mounted features that channel airflow to reduce rear drag, a particularly effective solution on three-box cars.
A slightly lower ride-height.
Altogether, Renault reduced the drag coefficient by some 20%, from 0.36 for the production Logan to 0.29, a score that makes Logan Renault eco2 Concept one of the most aerodynamically efficient three-box sedans. All the work aimed at reducing drag produced a CO2 gain of 5g/km.
Logan Renault eco2 Concept is equipped with new Michelin Energy Saver 185/65R15 low rolling resistance tires. This brought a CO2 gain of 2g/km (NEDC homologation cycle).
The use of low-friction rear bearings led to an emission gain of around 1g of CO2/km. The camber and toe settings were also optimized. Work on the running gear helped us make CO2 emission gains of 3g/km.
The active control alternator ensures that the battery is charged only as required (12.8 Volts instead of 13.5 Volts). The battery consequently doesn’t have to be charged so frequently, which leads to lower fuel consumption. Measures taken to reduce the effect of energy-hungry parts helped reduce CO2 emissions by 4g/km.
The sum of all the work that went into Logan Renault eco2 Concept achieved record low CO2 emissions of just 97g/km (NEDC combined cycle) equivalent to fuel consumption of 3.8 liters/100km (62 mpg US).
Furthermore, the extra-urban phase of the NEDC driving cycle returned UTAC homologated fuel consumption of just 3.4 liters/100km (69 mpg US), equivalent to CO2 emissions of 88g/km.
Driving style can also play a significant role when it comes to curbing fuel consumption and CO2 emissions. The dashboard of Logan Renault eco2 Concept features a gearshift indicator which enables drivers to make an active contribution to the optimization of fuel consumption.
By taking full advantage of this aid, drivers can bring Logan Renault eco2 Concept’s CO2 emissions performance below the homologated score of 97g/km.