Considering the price of petrol, anything that saves fuel has to be a good idea, right? Well Volvo certainly seems to think so as it forges ahead with its fuel saving stop/start technology.
The system Volvo calls ‘Geartronic’ is now fitted to the D3 turbo diesel in Europe.
The 2.0 litre D3 turbo diesel with the Geartronic automatic and stop/start technology cuts CO2 emission by 10g/kmand uses 0.4 litres less fuel per 100km, compared to a standard automatic transmission car with the same engine.
In cars with manual gearboxes the engine restarts when the driver depresses the clutch pedal. In the automatic, the engine restarts when the driver moves his or her right foot from the brake pedal to the accelerator.
The power train with start/stop is now available in the D3 versions of four Volvo models in Europe, the S60, V60, V70 and S80.
Volvo Cars New Zealand general manager Steve Kenchington says the technology is not available to us yet as it has only just been introduced in Europe. “Fuel efficiency is important to us and we will certainly be looking at stop/start with automatic transmissions when we can source it.”
Reducing CO2 emissions from conventional powertrains is an important part of Volvo’s drive towards zero emission strategy.
“It is the most effective way to cut CO2 throughout our model range in the short term. This work is running parallel with our innovative focus on electrification technologies,” says Peter Mertens, Volvo Car Corporation senior vice president of R&D.
Seamless response
“We have focused on achieving the same response as you get with today’s conventional automatic gearbox. The action is so seamless, that it feels like the car starts accelerating immediately when the engine restarts,” he says.
The technology uses brake pressure measurement to trigger when to stop and start the engine. The start/stop system is programmed to shut down the engine immediately when the car reaches a standstill. An electric pump keeps oil pressure up in the automatic gearbox while the engine is stopped. The system also includes an upgraded starter motor to cope with the increased number of starts.
The 2.0 litre D3 turbo diesel produces 120kW and 400Nm of torque. The five-cylinder diesel was introduced in the new S60 at the start of this year and is now available throughout Volvo’s model range.
It is, in principle, the same engine as the 2.4 litre diesel, but its displacement has been reduced with a shorter stroke to optimise fuel consumption.
The piezo-electric fuel injectors minimise consumption with exceptionally rapid and precise injection pulses under high pressure which results in extremely efficient combustion.
