Lotus is attempting to answer the noise problem posed by hybrid vehicles by developing external sound systems.
Hybrid cars are very quiet and as such they can pose a risk to members of the public who do not hear them coming when crossing roads.
But a new invention from Lotus is using an external sound system to simulate the noise made by a car to warn pedestrians of the oncoming traffic.
The ‘Safe & Sound’ technology is being used on a hybrid technology demonstration vehicle and Mike Kimberley, chief executive of Lotus, said it was important to do everything to encourage green motoring.
"Our advanced external sound synthesis technology increases pedestrian safety, while retaining the car’s environmental benefits.
"We hope that legislators introduce minimum noise requirements for vehicles to encourage the adoption of technologies," he explained.
The technology works by taking a road speed signal from the vehicle.
A waterproof speaker is then positioned next to the radiator to let the sound expand from the front of the vehicle.