Mercedes AMG Hyper-Hybrid Brings F1 to the Road

Mercedes-AMG is claiming to have brought current Formula One powertrain technology to the road by debuting its ONE two-seater sportscar.

To mark the 55th anniversary of the performance and sports car brand, the production version of the Mercedes-AMG ONE brings F1 hybrid drive technology to the road for the first time. The performance hybrid produces a total output of 1,048bhp from one combustion engine and four electric motors, with a claimed top speed capped at 219mph.

Despite the performance, hybrid system claims  a combined weighted fuel consumption of 32.4mpg (27mpg US) with combined weighted CO2 emissions of 198 g/km. The development was carried out in close cooperation with the race engineer experts at Mercedes-AMG High Performance Powertrains in Brixworth, England. The car will also officially be seen in action for the first time as part of the Festival of Speed at Goodwood between 23 and 26 June.

Its E Performance hybrid drive reflects those employed in F1 racing and uses a single turbo-charged 1.6-liter V6 gasoline engine and four electric motors. One of the electric units has been integrated into the turbocharger, another has been installed directly on the combustion engine with a link to the crankcase and the two remaining motors drive the front wheels.

The V6 gasoline engine uses four overhead camshafts are driven by spur gears. To achieve high engine speeds, the mechanical valve springs have been replaced by pneumatic valve springs. The engine, mounted in mid-engine position in front of the rear axle, revs up to 11,000rpm. However, for longer durability and the use of commercial super plus fuel, it deliberately stays below the F1 rev limit.

Its exhaust gas turbine and compressor turbine are positioned at a distance from each other and connected by a shaft. This allows a lower installation position for the turbocharger. On the shaft is an approximately 90 kW electric motor. Electronically controlled, this drives the turbocharger shaft directly, accelerating the compressor wheel up to 100,000rpm before the exhaust gas flow takes over.  The Formula 1 designation for this unit is MGU-H (Motor Generator Unit Heat).

The major advantage is that the response improves significantly, faster than a naturally aspirated V8 engine, immediately from idle speed across the entire rev range. In addition, the electrification of the exhaust gas turbocharger enables higher torque at low engine speeds. This also increases agility and boosts acceleration. Even when the driver takes their foot off the accelerator or brakes, the technology is able to maintain boost pressure at all times. This ensures a continuously direct response.

The electric exhaust gas turbocharger has yet another advantage in that it uses part of the surplus energy from the exhaust gas flow to generate electrical energy as a generator. This is either stored in the high-voltage lithium-ion battery or fed to the electric front axle or the electric motor (MGU-K = Motor Generator Unit Kinetic) on the combustion engine. The MGU-K has an output of 120 kW, is positioned directly on the combustion engine and is connected to the crankshaft via a spur gear system – another F1 innovation.

Turbocharging and direct injection with spray-guided combustion not only enable high power output, but also increase thermodynamic efficiency, thus reducing fuel consumption and exhaust emissions. The gasoline engine has two injection systems. Direct injection delivers the fuel into the combustion chambers at up to 270 bar pressure. This is a multiple process at times and is controlled by the engine management system as required. The additional port injection is needed to achieve the high specific power of the engine and at the same time comply with the exhaust emission limits.

Added to this is the complex exhaust gas cleaning system with four preheated metal catalytic converters, two ceramic catalytic converters and two petrol particulate filters. The four heating elements with a combined output of 16 kW make it possible to comply with the EU6 exhaust emission limits under real driving conditions (RDE). The exhaust gas cleaning system is also backpressure-optimized to avoid power losses. This also applies to the large rear silencer made of lightweight titanium.

To aid high speed performance, other F1 features include the carbon-fiber monocoque and carbon-fiber body to the load-bearing engine/transmission unit, active aerodynamics and the push-rod suspension.  On this road car there is also AMG Performance 4MATIC+ fully variable all-wheel drive with hybrid-driven rear axle and electrically driven front axle with torque vectoring. It can also drive purely electrically.

Philipp Schiemer, chairman of the board of management of Mercedes-AMG, said: “With the Mercedes-AMG ONE, we have more than pushed the envelope. The immense technical challenges of making a modern Formula 1 powertrain suitable for everyday road use have undoubtedly pushed us to our limits. Over the duration of the development period, many may have thought that the project would be impossible to implement. Nevertheless, the teams in Affalterbach and the UK never gave up and believed in themselves. I have the highest respect for all those involved and am proud of this team achievement. To put such a hypercar on wheels is certainly unique.”

— Paul Myles is a seasoned automotive journalist based in Europe. Follow him on Twitter @Paulmyles_