28 Jun 2011
Rüsselsheim. Models with especially low CO2 emissions tend to have weak to medium-powered engines. Low consumption and low emissions usually go hand-in-hand with low to mediocre performance. Opel is taking a different approach – with powerful ecoFLEX models. While the low-CO2 competitors in the compact class generally offer outputs of around 77 kW/105 hp, the new Astra ecoFLEX is equipped with a 96 kW/130 hp 1.7 CDTI turbo-diesel engine. It follows the successful Insignia ecoFLEX with 118 kW/160 hp and the Corsa ecoFLEX with 70 kW/95 hp in the range of dynamic Opel fuel-saving models.
The new five-door Astra ecoFLEX consumes just 3.7 liters diesel for 100 kilometers in the combined cycle. Its CO2 emissions of only 99 grams per kilometer make it the thriftiest and greenest Opel Astra ever. With 96 kW/130 hp, maximum torque of 300 Newton meters and six-speed manual transmission, the new green flagship of the compact class sets standards in performance and driving fun in Europe’s most important vehicle segment. Prices will be announced at market launch in the fall.
“The new Astra ecoFLEX is another milestone in Opel’s strategy for leading the industry in reducing fuel consumption and environmental effects while providing our customers with great performance and driving pleasure”,” says Karl-Friedrich Stracke, CEO of Opel/Vauxhall. “We will continue to pursue this strategy, which includes the launch of four new ecoFLEX models over the next six months, as well as the revolutionary electric Ampera that we will start to deliver by the end of the year”
In addition to the Astra ecoFLEX specific propulsion system with efficient thermal management, the package for the reduction of energy and fuel consumption – and thereby of carbon dioxide emissions – includes the intelligent recovery of electric energy through brake energy recuperation, active aerodynamic components and reduced rolling resistance. Altogether this has made it possible to reduce CO2 emissions (minus 20 g/km) and consumption (minus 0.8 liters/100 km) by 17 percent compared with the Astra 1.7 CDTI base model.
Newly developed engine management guarantees efficiency and dynamics
A new engine management system completely designed by Opel engineers for the 1.7-liter common-rail unit guarantees maximum efficiency. The maximum torque of 300 Nm is available at 2,000 - 2,500 rpm. The reduced compression ratio – combined with a new multiple injection system that carries out up to eight injections per cycle at 1,800 bar – improves the combustion process and reduces consumption. Also contributing to this is a new variable geometry turbo charger that provides especially precise boost-pressure control thanks to its additional positioner feedback sensor.
Cylinder pressure sensors enable precise combustion control
A modified reciprocating piston system also reduces consumption thanks to its lower friction. Synthetic diamond coating on the tappets and piston pins as well as friction-optimized piston rings also contribute to a further reduction of friction and thereby of wear on moving engine parts.
Together with the electronically-controlled variable mixture preparation, a weight-saving plastic intake manifold ensures efficient combustion. Cylinder pressure sensors in the glow plugs (Cleantech Combustion Technology) enable very accurate combustion control so that the center of combustion is always at a clearly defined position to the crankshaft.
At the same time, the low-voltage glow plugs ease the load on the generator during cold starts. To speed up the warm-up phase of the engine, an oil cooler bypass reduces pressure loss. This also saves fuel, as the engine’s operating temperature is more quickly reached. A switchable water pump ensures optimized engine heating.
Electronically-controlled exhaust gas recirculation with additional cooling function also contributes to the optimum temperature level for the low-emission combustion process. In addition, the NOx emissions are also reduced. Optimized platinum coating of the pre and main catalysts and the precise fine-tuning of both parts as well as their position close to the engine bring the emission control system to operating temperature more quickly, thus increasing efficiency.
Opel’s Start/Stop system reduces engine idling times
The Start/Stop system developed by Opel reduces engine idling times and consequently fuel consumption as well as the emission of greenhouse gases and noise – a big advantage for all road users, especially in city centers. The system automatically turns off as soon as the driver shifts to neutral and takes his/her foot off the clutch (Autostop phase). When it’s time to move on, the driver simply shifts into first gear and drives off. The Opel engineers have made sure that the engine immediately starts up when the driver steps on the clutch pedal. A high-performance battery ensures the electric system’s maximum reliability and that the engine immediately starts at all times.
For reasons of safety and passenger comfort, temperature controls and the brake booster vacuum control remain active during the Autostop phase. When deemed necessary, for instance in slow-moving stop-and-go traffic, the driver can manually deactivate the system with the “eco” switch located on the center console.
Exclusive six-speed manual transmission and energy recuperation system
While all low-CO2 competitors are equipped with five-speed transmissions, the Opel Astra 1.7 CDTI ecoFLEX has a friction-reduced six-speed manual transmission especially tuned to the new engine. Another standard ecoFLEX component is the shift indicator. The illuminated gauge between the speedometer and rev counter shows the driver the ideal moment to shift up, while an additional graphic assist function helps the driver to adopt a fuel-saving driving style.
To ensure optimum electrical energy management, Opel introduces a braking energy recuperation system which recovers kinetic energy via the generator in engine overrun mode, converting this to electrical energy and feeding it into the battery. This happens automatically when the driver takes his/her foot off the accelerator pedal or presses the brake pedal. When the battery is sufficiently charged, the generator output is greatly reduced and the electrical energy consumers are powered in a fuel-saving manner by the buffered electrical energy. This relieves the engine from having to drive the generator when accelerating and thus reduces consumption and emissions.
In addition, a clutch only activates the air conditioning compressor when it is actually needed. The standard LED daytime running lights also reduce energy consumption.
Active aeroshutter in the radiator grille and tires with low rolling resistance
For improved aerodynamics, the Astra ecoFLEX features an active aeroshutter integrated in the radiator grille. While it remains open to maintain optimal temperature at low speeds and when the engine is running under high thermal load such as on inclines and when in towing mode, the aeroshutter automatically closes at higher speeds and directs driving wind around the car. This results in improved aerodynamics, lower fuel consumption and lower CO2 emissions. The Astra’s 12 mm-lower chassis and 215/60 R 16 or 215/50 R 17 ContiEcoContact 5 tires with reduced rolling resistance further contribute towards lowering fuel consumption.
Opel ecoFLEX models combine driving fun with low consumption
The new Astra 1.7 CDTI ecoFLEX seamlessly joins the range of Opel’s especially low CO2 and powerful diesel models. These include:
Opel is investing around one billion euro in the development of new, cleaner propulsion systems. The wide spectrum of activities ranges from downsizing and optimizing the engine range, offering liquefied petroleum gas and natural gas vehicles to developing completely new alternative powertrain systems. The introduction of Start/Stop is also a part of this – by the spring of 2012, the company will offer 34 vehicle-engine combinations with this technology, including all Astra diesel and gasoline models with manual transmission.
Opel is the first European carmaker to introduce an electric vehicle suitable for everyday use with the launch of the Ampera (111 kW/150 hp, 40 g/km CO2 and 1.6 l/100 km – provisional data pursuant to ECE R101) at the end of this year.
At a glance – measures for CO2 reduction in the Astra 1.7 CDTI ecoFLEX:
Images may show optional equipment.