A new report today exposes the real green cars - and there's not a hybrid in sight in the top 10, according to researchers at Cardiff University.
Conventionally engined superminis dominate the top ranks. The scientists gave half their score based on each cars' emissions of CO2, NOx and other pollutants; the other half of the score was calculated from vehicles' construction, energy costs, recyclability and size. The higher the score, the cleaner the car:
• 1st Smart Roadster - 66.2 points
• 2nd Smart Fortwo Cabriolet - 59.8
• 3rd Citroen C1 1.0 - 40.1
• 4th Peugeot 107 1.0 - 38.6
• 5th Citroen C1 1.4 HDI - 31.3
• 6th Fiat Panda 1.2 Dualogic - 28.4
• 7th Ford Ka 1.3 - 27.5
• 8th Toyota Yaris 1.0 - 27.2
• 9th Fiat Panda 100hp - 23.6
• 10th Pegueot 206 1.4 - 23.5
• 11th Mini Cooper D - 23.3
• 12th Toyota Prius 1.5 - 23.2
The report authors at research agency Clifford Thames and Cardiff University acknowledge that it's difficult to compare differently sized cars, but it applied the same methodology to all models in its survey. Some of the models have since been discontinued, including the cleanest, Smart's defunct Roadster.
Although the petrol-electric Prius appeared in twelfth position, it was held back by its whole-life environmental impact, researchers said. The message here is - small and lightweight is the best way to reduce environmental impact.
Dr Paul Nieuwenhuis from Cardiff Business School predicts that hybrid tech and clean-fuels know-how is not enough for the industry to hit Europe's proposed 130g/km CO2 targets, that will be debated at the European Parliament in Brussels on 16 October 2007.
Weight loss is crucial if the industry is to hit these ambitious fleet averages. Nieuwenhuis claims there will be numerous hidden benefits from a gradual greening of all cars large and small. 'Large luxury cars tend to lose value quickly compared with small hatchbacks,' he said. 'This is due to the fact that used car buyers tend to be less affluent, thus less able to afford the high running costs of heavy cars.
'If luxury cars were smaller and lighter, their appeal to the used market would rise, thus boosting residual values. This would impact on the overall lifecycle costs of luxury cars, making them generally more economically competitive. Not only would customers benefit, but so would manufacturers as higher residual values would boost their brand image.'