Renault 2014 power unit - side view 17 April 2014
If we compare the component installations on Renault's and Mercedes' power units, it is easy to see how different their concepts are. One of the fundamental requirements of a turbocharged engine is to reduce the temperature of the charge air (the blue part of the turbo) - the cooler this charge air is, the more power the engine will produce. Unlike Mercedes, Renault have the hot side of the turbo (shown in red) bolted directly to the cold side (in blue). There is heat insulation between them, but there will inevitably still be a lot of heat transfer between the two parts, meaning that a larger intercooler and more airflow will have to be used to reduce the charge air temperature. Mounted to the cold side of the turbo is the MGU-H, which will drive or be driven by the turbo through a central shaft. With this packaging both turbo elements will be driven simultaneously (whereas Mercedes' solution offers the possibility of driving the two elements independently).