How does Mercedes-Benz define "BlueEFFICIENCY"?

This term refers to a whole package of energy management measures which, when combined and coordinated, have resulted in consumption of 0.9 L/100 km for the C 180 KOMPRESSOR and 0.6 L/100 km for the C 200 CDI.

What is energy management?

Energy management is a method of systematically reducing energy losses or recovering energy and then providing it once more as required. This is a process in which developers from various areas analyze the interactions of their respective components and coordinate them in terms of an overall energy budget.

How does energy management work in the case of the C-Class BlueEFFICIENCY models, for example?

By systematically reducing air resistance through low rolling resistance tires, smart weight reduction, and optimized dynamics, we were able to approach the next stage of downsizing for the Mercedes-Benz C 180 KOMPRESSOR. Because we simultaneously reduced friction inside the engine in this process, we were able to offer our customers engines with the same power output in spite of the smaller displacement.

Another crucial component is the regulated auxiliary steering pump, a beautiful example of smart energy management. In conventional hydraulic steering systems, the pump has to constantly maintain maximum volume flow, independently of the driver's steering requirements. We've built in an additional valve, so that we can now regulate the flow requirements according to the driving situation, thus saving 0.14 L/100 km.

What exactly does this mean for customers?

For one thing, customers will be driving a vehicle with the same high level of comfort and safety that is typical of a Mercedes. One very good example of this is the weight package, which lightens the vehicle by 20 to 30 kilograms without any sacrifices in terms of noise comfort. One element of this package is the newly developed windshield, which contains a soundproof layer of plastic foil. That enabled us to reduce the windshield thickness and thus cut the weight by approximately 1.2 kilograms. We've achieved additional fuel savings by using ultramodern simulation processes. When we redesigned the bulkhead insulation we adjusted the strength of the material to the actual noise conditions. As a result, we were able to reduce the weight of the covering of the entire bulkhead area by 20 percent.

How do customers benefit from the BlueEFFICIENCY package?

In addition to creating the engine and weight packages I've already mentioned, we've also systematically refined the aerodynamics of the C-Class, whose Cd value of 0.27 already makes it the market leader in its segment today. Here too, the combined effect of several measures — ranging from the aerodynamically optimized side mirrors to the headlight coverings and the smooth underbody — has improved the model's Cd value to 0.25. This reduction of 0.02 corresponds to fuel savings of 0.07 L/100 km in the prescribed testing cycle.

The seemingly small effect is due to the relatively low average speed of approximately 33 km/h in this driving cycle. But because we look closely at the way our customers use their vehicles, we know that they travel at an average speed of over 50 km/h in the annual mean. Under these real-life conditions, the aerodynamics package of the BlueEFFICIENCY models results in fuel savings of more than 0.15 L/100 km. And when a customer drives at an average speed of 120 km/h on the highway, he or she saves as much as 0.3 L/100 km.

How will the BlueEFFICIENCY package be visible to the customer?

The only visible difference in the BlueEFFICIENCY models will be the aerodynamics package, especially in the changed design of the side mirrors. In addition, the BlueEFFICIENCY models will have a shift recommendation display on the control panel when they're launched on the market. Via this display, the engine control unit will notify the driver as soon as another gear — the next-highest one, as a rule — would be more fuel-efficient in a given driving situation. This will enable even drivers who are not skilled at estimating fuel consumption to achieve fuel savings of up to ten percent.