Vauxhall is introducing a range of greener vehicles, dubbed ecoFLEX, which it says offer lower CO2 emissions and better economy.
At the head of the eco charge is the recently tweaked Corsa 1.3 CDTi. In 74bhp form this now emits 119g/km of CO2 – down from 124g/km when the car was first released.
Vauxhall says it is also using smaller, more efficient turbocharged engines - subbed Eco-Turbo - in place of large units. For example, Vauxhall claims that the Astra’s 2.0-litre 168bhp turbo engine is being replaced with a 178bhp 1.6 turbo, saving a claimed 14 per cent of fuel and in turn reducing CO2 emissions by the same amount.
The sharp-eyed among you will, of course have noticed that this is nothing new; in fact, the engine change was announced in November 2006, when the Astra was facelifted.
Vauxhall is also to introduce stop-start systems, high-efficiency alternators, and widen the use of electric power steering, all of which save fuel.
A range of bioethanol-burning Vauxhalls will also be available from 2010, but if you can’t wait that long an E85 bioethanol version of the Cadillac BLS will be available from autumn 2007.
In the longer term, GM is still working on hydrogen cars – it will unveil its latest hydrogen concept, the HydroGen4, at the Frankfurt motor show in September.