Renault Shows Three Advanced-Engine Prototypes

Renault SA has unveiled three next-generation powertrain prototypes: a mild diesel hybrid; a 2-cylinder, two-stroke diesel; and a light-duty electric delivery system for urban applications.

The mild diesel hybrid combines a 48-volt starter motor/alternator built into the gearbox. The transmission is geared to allow a small twin-turbo diesel to run at lower speed, thus reducing internal friction. The system was designed to improve fuel economy for light commercial vehicles about 10% over long distances.

The two-stroke diesel is a 730-cc engine that capitalizes on the inherently superior efficiency of a two-stroke versus four-stroke design (nearly 50% compared with less than 35% for a four-stroke/4-cylinder diesel). The concept engine is half the size and weighs 88 lbs (40 kg) less than a conventional four-banger. Renault says the unit, which is fitted with a turbocharger and supercharger, generates as much as 67 hp and 107 lb-ft of torque.

The company's third concept is an electric urban delivery vehicle based on Renault's little Twizy EV. The Twizy adds a trailer able to hold as many as 15 adjustable load boxes occupying one cubic meter. Renault describes the system as a zero-emission alternative for urban deliveries.