Sales of Nissan cars in the US dropped in 2007. Announcing its yearly figures, the automaker revealed that it sold 1.057 million units in the US in the last business year. Demand for larger trucks such as the Titan pickup dropped and other big vehicles became less popular as consumers leaned towards greener, smaller models.

However, Nissan did announce increased sales in China, Russia and other emerging markets and a commitment to deliver top quality products, services, brands and management.

In the last month, Clean Diesel Technologies has announced huge increases in product sales - driven by the need for cleaner cars. The firm announced that first quarter product sales in this year exceeded the full product sales of 2007. It saw strong sales of its Purifier System that controls particulate matter emissions. A need for the technology was attributed to the London Low Emission Zone (LEZ) programme that requires firms to reduce emissions in the capital.

Clean diesel fuels offer improved efficiency, better fuel economy, reduced emissions and more power, it has been claimed. Gale Banks, the Chief Executive Officer of Gale Banks Engineering, said that diesel power means that fuel economy and performance are not "mutually exclusive". He was speaking at a reception sponsored by Robert Bosch LLC and said that "clean diesel provides guilt-free performance".

Ford is engineering the green cars of the future in its plant in Dagenham. The automaker continues to roll out big engines for large gas guzzling vehicles but behind the scenes it is also investigating some of the cars of the future. About 500 people in protective clothing create low-emission cars to be used all over Europe, the Guardian reported. Last year, Ford constructed over 150,000 low-emission diesel engines for Europe and it expects this to increase to 450,000 this year. The automaker also hopes to increase the consumption figures of the engines to 70 miles per gallon.

Increases in fuel prices are beginning to hit consumers and forcing them to look for other qualities in their motor cars. According to the Society of Motor Manufacturers & Traders (SMMT), consumers want efficient cars that "they can afford". As a result registration figures have shown an increase in the number of diesel cars hitting the UK market. Registrations for April showed that 45.4 per cent of new cars were a diesel model.