Renault has unveiled a diesel particulate filter that allows for active regeneration when the car is at a standstill.

The system, being shown at the Geneva Motor Show, will be the world's first regenerating particulate filter with exhaust post-injection and will cut harmful emissions.

Most particulate systems have relied on engine post-injection, meaning that the engine temperature needs to increase significantly before the system can work properly.

The new filter, which will become available in versions of the Clio and Modus 1.5 dCi diesel engines, works with exhaust post-injection. This allows for the particulate filter to be regenerated at all engine speeds, even when the car is idling.

This makes it ideal for inner-city traffic conditions, when cars frequently move at low speeds and stop at traffic lights.

Meanwhile Manchester engineering firm Per-Tec has developed an electrostatic diesel particulate reduction device that begins working as soon as the vehicle is started up.

The technology will help drivers of diesel vehicles when they face charges to drive into the proposed central London Low Emission Zone if their engines do not meet required emissions standards.

Ÿ Adfero Ltd