The iconic hybrid car is still the cleanest for its size, but is outranked by nine smaller models from Peugeot, Citroën, Ford, Smart and other manufacturers in a new environmental rating system.
The researchers also studied cars due to launch shortly, and claim that petrol and diesel cars with new emissions-cutting technology will soon outpace the Prius on a size-for-size basis. They also say that conventional technology will overtake the Prius over the next 12 to 18 months, and consumers won’t have to pay a premium for it.
The research, based on publicly available data, points to the huge improvements manufacturers – under pressure from regulators to reduce emissions – are making on non-hybrid cars with diesel or petrol engines.
Rather than focusing on tailpipe emissions only, the ranking also takes into account cars’ overall environmental 'footprint' – including raw materials, production, and end-of-life costs – based on their length, width and weight.
Though the Prius is the best-selling hybrid in the world, and still one of the lowest-emission cars on the road, it's also larger and somewhat heavier than many rival low-emission vehicles because of its large battery and transmission.