F1 is the laboratory for normal, daily used cars. In the below article, I will explain how the ERS (Energy Recovery System) works and its benefits. Previously known as KERS (Kinetic Energy Recovery System), which was first introduced in 2009, the ERS can be simplified as follows:

We all remember when we were kids the toy cars that we used to have. Remember how we used to drag the car backwards several times and then leave it on the floor and the car used to quickly accelerate from our hands? We all remember that, right? The car accumulates the energy in something called the “flywheel” from dragging the car backwards and releases it once we leave it on the ground.

The ERS is more complicated than that, but the example was to make you remember and understand how every moving object in physics generates energy. What ERS does is to store this energy and release it once needed. It is now called Motor Generator Units or MGU.


The Motor Generator Units convert mechanical and heat energy to electrical energy and vice versa.

The two parts of ERS are: Motor Generator Unit – Kinetic (MGU-K), and Motor Generator Unit – Heat (MGU-H), plus an ‘energy store’ (ES) and control electronics. Renault describes its energy store as a “battery”.  Other manufacturers call their engines now the “Power Unit”. The new ERS must weigh between 20 to 25kg.

MGU-K, like KERS, uses a motor-generator to deliver power (120kW) for acceleration and extract energy instead of friction brakes for deceleration. MGU-K works like an upgraded version of KERS, converting kinetic energy generated under braking into electricity (rather than it escaping as heat). It also acts as a motor under acceleration, returning up to 120kW (approximately 160hp) power to the drivetrain from the Energy Store.


MGU-H also uses a motor-generator, connected to the turbocharger. Energy extracted can be used to feed the MGU-K directly, stored for later use by the MGU-K, or stored to be feed back into the turbocharger. MGU-H is an energy recovery system connected to the turbocharger of the engine and converts heat energy from exhaust gases into electrical energy. The energy can then be used to power the MGU-K (and thus the drivetrain) or be retained in the ES for subsequent use. MGU-H also controls the speed of the turbo, speeding it up (to prevent turbo lag) or slowing it down in place of a more traditional waste gate.

The 2.4 liters normally-aspirated V8 engines of 2013 produced around 750hp, with an additional 80hp available for around six seconds per lap from KERS. The 2014 V6s put out around 600hp. However, the two ERS systems (ERS-K and ERS-H) will give drivers an additional 160hp (120kW) or so for approximately 33 seconds per lap while previously, KERS used to give the driver around 80hp.

About The Author

Cars and Motorsports have fascinated me since I was a kid. Born in 1968, my hobby for cars and motor sport in general started in 1980. Despite working in the telecommunication sector since 1996, my passion for the sound of engines never faded over the years. I make sure to follow the Local Lebanese motorsport events live and I do my best to watch similar events live abroad whenever I have the chance. I am married with two wonderful kids.

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