Petrol or diesel: which should you buy? - Is the end nigh for petrol?

Diesel, it seems, is the new black. Since 1999, sales of diesel-powered cars in the UK have tripled.

Until April this year, 40% of new car registrations were diesel, and by 2009 the car industry reckons diesels will make up 60% of new cars sold.

Is this the end of the petrol car? A survey on whatcar.com suggests petrol-run cars will no longer be the first choice for car buyers - 62% of respondents will choose diesel and only 28% will go for petrol power when they next replace their car.

The rest said they will opt for greener forms of power and will go for hybrid or bioethanol-run cars.

The thirst for diesel is fuelled by the low carbon dioxide emissions, low tax and low fuel consumption diesel cars offer, combined with the way they now offer genuinely lively performance.

However, there are many other factors to consider if you're planning to ditch petrol - diesel may not be the cheap choice it seems on the surface.