|The coming ecoFLEX Corsa 1.3 CDTI emits 119 g/km of CO2 (equivalent to about 4.4 l/100km fuel consumption or 53 mpg US). Click to enlarge.|
In a press briefing in Berlin today, GM Europe outlined an environmental strategy that focuses in the short-term on reducing CO2 emissions through engine downsizing, systems optimization (through the use of technologies such as start/stop) and alternative fuels (including CNG and E85); and in the long-term on introducing new propulsion technologies.
The strategy includes the use of downsized ecoTurbo engines in ecoFLEX models in each Opel/Vauxhall model line, with new models making their debut at the Frankfurt motor show (IAA) in September. GM will also use the IAA for the introduction of its next-generation HydroGen4 (the European counterpart to the fuel-cell Equinox in the US), and for an Opel diesel-engine variant of the E-Flex architecture (currently embodied in the two variants of the Chevrolet Volt). E-Flex, said GM Vice Chairman Bob Lutz during the briefing, “is the top priority program for GM.”
GM Europe also announced that Cadillac will launch its BLS model as an E85 variant in fall 2007, and that Opel/Vauxhall and Chevrolet will offer E85 technology in their vehicles as of 2010.
ecoFLEX. GME Europe launched ecoFLEX as a broad environmental initiative earlier in June with the announcement of a campaign to encourage the scrapping of older cars which do not meet current environmental standards. EcoFlex also serves as the umbrella for GM’s shorter-term initiatives on improving fuel consumption and reducing greenhouse gas emissions through the use of downsized, turbo-charged engines and the optimization of a number of other vehicle systems.
Downsized Eco-Turbo and CNG (Compressed Natural Gas) engines are at the core of Opel/Vauxhall’s ecoFLEX models. Engines with larger displacements are being replaced by new Eco-Turbo units with smaller displacement.
The new engines operate at higher efficiency than the naturally aspirated units, leading to a significant reduction in fuel consumption and CO2 emissions. This reduction is achieved through less friction and increased thermal efficiency by shifting the operating points to higher loads.
The Eco-Turbo concept is used in both gasoline and diesel engines. For example, the 1.6 turbo gasoline-fueled ECOTEC in the Opel Astra (132 kW/180 hp) replaces the older 2.0-liter turbo (125 kW/170 hp), reducing fuel consumption by 14%. The new 1.7 CDTI turbo-diesel (81 kW/110 hp and 92 kW/125 hp) consumes 7% less fuel than the 1.9-liter diesel engines (74 kW/100 hp and 88 kW/120 hp) it replaces. There is no penalty in acceleration or top speed; the three new engines deliver slightly higher performance.
GM Europe (GME) is also successively adapting gasoline engines with larger displacements to direct injection. Current offers are the 2.2 DIRECT ECOTEC in the Opel/Vauxhall range, and the 2.0 turbo ECOTEC unit from the new Opel GT, which boasts a power output of 132 hp per liter. This engine also features “Cam-Phase” variable camshaft phasing, which together with other measures reduces fuel consumption by a further 3 to 10 percent. The 1.6 and 1.8 TwinPort ECOTEC engines also feature this technology.
Opel/Vauxhall will unveil more ecoFLEX models at the Frankfurt motor show in September. The premiere model is a Corsa 1.3 CDTI emitting 119 g/km of CO2, which will be launched in 2008.
Systems efficiency and start/stop. GME aims to further reduce fuel consumption in the short and mid-term through a number of technologies. These include:
The introduction of Electric Power Steering (EPS) across all model lines;
The use of start/stop systems;
A High Efficiency Alternator in cars without the start-generator system for start/stop;
A Variable Displacement Oil Pump (VDOP) that only pumps as much lubricant into the engine as needed;
Low-rolling resistance tires; and
Enhancements to vehicle aerodynamics.
E85 and CNG. In the mid-term, GM will increase the number of its models that run on alternative fuel. Cadillac will offer an E85 variant of its BLS as of this fall, followed by Opel/Vauxhall and Chevrolet Europe in 2010. Saab will feature its BioPower flex-fuel engines throughout the 9-3 model line s of this fall.
Opel currently offers two models with compressed natural gas (CNG) 1.6-liter engines: Zafira CNG and Combo CNG (Compressed Natural Gas). These consume 5.0/4.9 kg of gas per 100 km (corresponds to 138/133 g CO2/km respectively). Opel’s CNG cars offer low operating costs (50% below that of gasoline or diesel in Germany), beat the strictest exhaust standards by up to 80%, and offer a range of up to 380 km in CNG operation and ensure unrestricted use of the passenger compartment and trunk.
The 1.6-liter engine operates on CNG, biogas or any mixture of the two. Opel plans to introduce a more powerful turbocharged CNG (“TNG”) engine.
E-Flex. E-Flex—not to be confused with ecoFLEX—describes an all-electric drive architecture that can use a variety of sources to provide the electric power. GM introduced E-Flex in January 2007 at the Detroit auto show with the unveiling of the first variant of the Chevrolet Volt—a plug-in series hybrid that uses a small flex-fuel engine for a genset coupled with a lithium-ion battery pack. (Earlier post.)
At the Shanghai motor show, GM introduced a second E-Flex variant: a Volt that combines a hydrogen fuel cell with a lithium-ion battery pack. (Earlier post.) GM is co-developing both of these E-Flex models with the intent that they both go into production, Lutz said at the briefing.
Earlier, GM announced that it had awarded battery development contracts to both CPI and Continental for the E-Flex. (Earlier post.) One of those battery systems will end up as the production system, according to Lutz.
GM will unveil a third E-Flex application at the Frankfurt show in September: an Opel concept model that uses a diesel engine in combination with the electric drive system of the E-Flex architecture.