Britain's cleanest cars - Coupes & performance

What Car? Greenest Coupe and Performance Car: Smart Roadster

The ultimate sports car for the recycling generation has to be the distinctive, featherweight Smart Roadster.

Powered by the same 0.7-litre petrol engine as the original Smart (the Fortwo city car), the standard Roadster returns an astonishing 55.4mpg and produces just 121g/km CO2.

Even the higher-powered 101bhp Brabus version is only slightly more consumptive, with 126g/km and 53.3mpg.

The open-top Roadster is as nimble as its looks suggest, although that semi-automatic gearbox takes some getting used to. The bad news is that the UK's greenest sports car will bow out this year as Smart's financial strife takes its toll.

However, for now, there's no more enjoyable way to cut back on CO2 emissions.
Price: From £13,515
MPG: 55.4
CO2 emissions: 121g/km

Peugeot 407 Coupe 2.7 HDI
Mile-eating coupes often have V6 petrol motors, but they're no friend to the environment, producing high emissions and high fuel consumption.

This one scores highly by using a refined V6 diesel to provide power and half-decent economy. A particulate filter removes soot emissions.
Price: From £26,295
MPG: 33.2
CO2 emissions: 226g/km

Alfa GT 1.9 JTD
Coupes are an indulgence, but with the Alfa GT, the only sacrifice is space.

Economy is as good as a small hatchback's, at 45.6mpg for the 150bhp 1.9-litre diesel. Such thrift means the head-turning GT emits just 165g/km of CO2.

Although it's never going to be as fast as the 240bhp 3.2 V6 range-topper, the diesel still manages to dispatch the 0-60mph sprint in under 10sec.
Price: From £21,200
MPG: 45.6
CO2 emissions: 165g/km