Stop-start technology improves the Astra's fuel economy by 5mpg according to Vauxhall
Vauxhall has announced that its 2.0-litre diesel Astra will fitted with stop-start technology - improving emissions and economy without compromising performance.
Officially called the Vauxhall Astra 2.0 CDTi Start/Stop, the new model replaces the regular 2.0-litre diesel, and is available as both a five-door hatchback and Sport Tourer estate.
Want to know how stop-start works? Read our guide
The Astra Start/Stop works in much the same way as any other start-stop system - whenever you are at idle in neutral, it switches off the engine to save fuel.
The system then restarts the engine as soon as the clutch is depressed. Various modifications are required to make this work, including a high performance battery, tougher starter motor, and energy management system. But the pay-offs are improved fuel consumption and emissions, especially around town.
Despite this, the Astra can still sprint from zero to 60mph in just 8.5 seconds.
Read about more green car technologies here
Vauxhall reckons the hatchback achieves a 13% reduction in fuel consumption in urban driving, while the official combined figure rises from 57.6mpg to 62.8mpg. This is enough to see CO2 emissions fall from 129g/km to 119g/km, dropping the hatch into the lower £30 annual tax band - compared with the previous £95 a year.
The Sport Tourer estate, meanwhile, sees its official fuel economy improve from 55.4mpg combined to 60.1mpg combined.
Alongside the stop-start system, Vauxhall is also citing new CleanTech Combustion Technology as part of the reason for the improvements. This is a refinement of the fuel injection process, coupled with reduced friction camshaft bearings, boosting refinement as well as efficiency.
The new Vauxhall Astra Start/Stop replaces the previous 2.0-litre CDTi model with manual gearbox - those specifying an automatic gearbox are not able to take advantage of the new system.
It's priced from £22,430 in hatchback form, and £23,430 for the Sport Tourer, and comes in SRi, SE and Elite (hatch only) specification levels.
Almost all Vauxhall models are set to benefit from stop-start technology before Spring 2012.
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