Renault has showcased two future innovations based on its Eolab prototype, both of which are scheduled to appear in production cars in 2015.
All were unveiled at an Innovations@Renault event in Paris, where the company’s Co-operative Innovations Laboratory (LCI) – a think tank that unites engineers, designers and customer survey specialists – gave a behind-the-scenes peek into how Renault powertrains and propulsion systems might evolve in the next few years.
Renault has developed a new, more efficient and more compact electric motor and a modern turbocharged petrol engine adapted for use with LPG (liquified petroleum gas), both of which are scheduled for introduction next year.
Looking further ahead, Renault and its partners are looking at a mild hybrid diesel prototype (HYDIVU project), a diminutive two-stroke diesel engine (POWERFUL project) and a small electric delivery vehicle based on the Twizy (VELUD project) as the basis for clean, low-cost urban mobility.
The new, compact electric motor – designed and made entirely by Renault – delivers similar performance to those in use today but is around 10 per cent smaller. It is a synchronous unit with a wound rotor and delivers 65 kW and 220 Nm of torque. It was designed by Renault’s motor engineers in France and manufactured in Renault’s Cléon plant.
Renault’s new dual-fuel petrol/LPG engine promises 25 per cent lower fuel bills and 10 per cent lower CO2 emissions than a comparable petrol-only power unit. It is a three-cylinder engine featuring a turbocharger, engine Stop&Start, brake energy recovery and an eco-mode, and it complies with EU6 emissions regulations. Achieving the right balance between turbo boost and LPG pressure while allowing maximum use in LPG mode with no input from the driver presented a severe technical challenge for Renault engineers.
The HYDIVU (Hybrid Diesel for LCVs) research prototype aims to reduce fuel consumption and therefore running costs for high-mileage business users. It is based on the Master van powered by Renault’s ENERGY dCi 165 Twin Turbo diesel engine, and has been engineered in conjunction with a number of European partners.
It integrates a 48-volt (10-12 kW) starter motor and alternator-type electric motor mounted on the gearbox to deliver additional torque and reduce the load on the combustion engine. Its positioning, as close as possible to the wheel, promotes greater efficiency by allowing maximum recovery of energy during deceleration and braking. This ‘free energy’ is stored in the 48-volt battery to be used as extra torque on demand.
The power unit also features what Renault calls Downspeeding – longer gear ratios which reduce engine revolutions when cruising to lower fuel consumption – while the twin turbos with variable geometry have been specially adapted to this concept.