|CO2 emissions of the C 180 in comparison to its predecessor [t/car]. Source: Mercedes-Benz. Click to enlarge.|
Over the course of its entire life cycle—from its manufacture through 200,000 kilometer of driving to its recycling—the new Mercedes-Benz C-Class (earlier post) produces around 10% fewer CO2 emissions than its predecessor at the time of its market exit (compared to the time of its launch in 2007 the improvement is much higher, at around 28%). The C 180 (115 kW) with manual transmission was taken as the base variant of the new C-Class at market launch for the lifecycle analysis; it was compared with the corresponding preceding model. The analysis was validated by TÜV SÜD Management Service GmbH.
Over the entire lifecycle of the C 180, the lifecycle analysis yields a primary energy consumption of 521 gigajoules (corresponding to the energy content of around 16,000 liters of gasoline); an environmental input of approx. 35 tonnes of CO2; around 19 kilograms of non-methane volatile organic compounds (NMVOC); around 25 kilograms of nitrogen oxides (NOx); and 37 kilograms of sulfur dioxide (SO2). For CO2 emissions—and likewise for primary energy consumption—the use phase dominates with a share of 78 and 74% respectively.
Production of the new C-Class results in a higher CO2 emissions than in the case of the predecessor (7.3 t vs. 6.5 t); however, CO2 emissions over the entire lifecycle are however clearly lower for the new C-Class (34.5 t vs 38.3 t).
Over the entire lifecycle, the new C-Class shows advantages compared to its predecessor in terms of CO2, NOx, NMVOC and CH4 emissions, as well as in the impact categories of global warming potential, acidification, eutrophication and summer smog. Emissions of sulfur dioxide are on a par with those of the preceding model.
In terms of carbon monoxide (CO) emissions during the operation of the vehicle, a significant improvement was achieved over the 2007 predecessor. It was not possible, however, to achieve the very good figure shown by the preceding model at the time of market exit, Mercedes-Benz said. The CO emissions of the new C-Class during operation are 76 % below the level stipulated by the Euro 6 standard that comes into effect in 2015.
|Selected result parameters for the C 180 compared with its predecessor from 2013 [unit / car]. Click to enlarge.|
Because of the shifts in the materials mix of the vehicles, the material resources requirements for manufacturing also changed. For example, the iron demand is less because the share of steel is less, while the bauxite demand increases because of the higher light alloy share. Where energy resources are concerned, lignite, hard coal and uranium figure principally in car production.
The new C-Class shows a slightly higher level in this respect than its predecessor. Natural gas and crude oil are strongly influenced by fuel consumption during the use phase.
In total, through the production and use phases, substantial savings are achieved owing to the significantly reduced fuel consumption of the new C-Class.
Compared with the predecessor, primary energy savings of 8% (2013) and 25 percent (2007) are achieved over the entire life cycle. The fall in primary energy demand by 45 GJ (2013) and 170 GJ (2007) corresponds to the energy content of about 1,400 and 5,300 liters of gasoline respectively.
The new C-Class. The new C-Class, features a lightweight design concept with weight savings of up to 100 kg (220 lbs); excellent aerodynamics; and new, economical engines (along with a hybrid model).
The aluminium hybrid body is around 70 kg (154 lbs) lighter than a conventional steel body. The overall weight savings of up to 100 kg delivers numerous benefits: the lightweight construction of the new C-Class cuts fuel consumption by up to 20% without any loss of performance, while at the same time allowing a lower center of gravity, which in turn gives rise to the vehicle’s sporty and agile handling.
|The new C-Class. Click to enlarge.|
Compared with the predecessor, total aluminium content in the new C-Class has increased from less than 10% to almost 50%.
The C 180 with manual transmission shows a drop in fuel consumption in comparison to its predecessor from between 7.6 and 7.4 l/100 km (31 mpg US and 31.8 mpg) at the time of the market launch in 2007 or from between 6.4 and 5.8 l/100 km (36.8 and 40.6 mpg) at the time of discontinuation in 2013 to between 5.5 and 5.0 l/100 km (42.8 and 47 mpg)—depending on the tires fitted.
This corresponds to a reduction in fuel consumption of up to 32%. The diesel variant also ensures a very high level of efficiency. The fuel consumption of the C 220 BlueTEC with manual transmission stands at 4.2 to 4.0 l/100 km (56 mpg to 58.8 mpg)—depending on the tires.
A package of measures ensures the fuel efficiency of the C-Class. These extend to optimization measures in the drive system, energy management and aerodynamics, as well as to tires with optimized rolling resistance, weight reduction through lightweight construction techniques and driver information to encourage an energy-saving driving style. Mercedes highlights the most important measures as including:
For all gasoline and diesel drive systems: Friction-optimized downsizing engines with turbocharging, direct injection and thermal management; gasoline engine with Camtronic (C 180).
The start/stop system as standard for all engine variants.
Regulated fuel pump and oil pump that adjust their output according to the required load.
Electric water pump, which makes on-demand operation possible (C 180 and C 200).
Use of tires with optimized rolling resistance.
Friction-optimized 6-speed manual transmission and 7-speed automatic transmission 7G-TRONIC PLUS.
Fuel-economy rear axle differential with tapered roller bearings with reduced power loss and low-friction oil.
Aerodynamic optimization courtesy of an optimized underfloor panelling concept comprising extensive panelling of both the engine compartment and the main underfloor, radiator shutter and wheels.
Wheel bearings with substantially reduced friction.
Weight optimization through the use of lightweight materials.
Intelligent alternator management in conjunction with an efficient generator ensures that consumers are powered from the battery during acceleration, while during braking part of the resulting energy is recuperated and fed back into the battery.
Highly efficient refrigerant compressor with magnetic clutch, which avoids losses caused by the drag power.
Optimized belt drive with decoupler.
The diesel hybrid model will features a second-generation hybrid module consisting of the combustion engine, the electric motor, the 7G-TRONIC transmission, the combined power electronics with DC/DC converter and the high-voltage lithium-ion battery.
|Fuel efficiency measures in the new C-Class. Click to enlarge.|