Kinetic Energy Recovery System

By admin No comments


Energy is the buzzword in any person’s life and the world in general, as, over the past few decades, we have been needing more and more electrical power for our everyday utility. And, thereby we are now more dependent on the state to meet our everyday energy demands, be it in a domestic or an industrial setup. What would you say if I told you, we could loosen that bondage a bit by harnessing energy from one of our daily activities, which otherwise goes waste? Take driving a car for instance – how cool would it be if we could generate energy from a moving car to help reduce its own fuel consumption?! And, while you thought braking decreases your speed, here’s a way to increase your car’s speed as you brake. It is true – read on. KERS is one such technology that harnesses the deceleration energy from the braking system of a vehicle and stores it for later acceleration. Storage of energy could be through a conventional electrical generator setup, or purely through a mechanical storage device, such as the flywheel.

The technology gained prominence during its introduction into Formula One racing in 2008, when teams started testing it to overcome the stricter regulations that mandated engine manufacturers to work with smaller engines. The manufacturers had to look for viable options to boost output power within the engine capacity guidelines, and in 2009 F1 allowed the optional use of this technology in race cars. The cars could enjoy a power boost for a brief period by the release of the energy generated during braking and stored in a KERS system. The excess boost could provide valuable thrust through which drivers could achieve top speeds quicker as they exited corners. Evidence of the success of KERS could be derived from the instance when Kimi Raikonnen used a KERS-installed car to overtake Giancarlo Fisichella in the closing stages of the 2009 Belgian Grand Prix to win the race. (Link)

Fig 1: Flybrid Systems KERS (Courtesy: The Internet)

Working of the technology

The central technology in KERS systems is the Toroidal Traction Drive Variator originally developed by Torotrak, which holds the patent for it. The system works on the basis of allowing the rotating wheel of the car to turn a conductor inside an electromagnet in a conventional generator setup to generate electrical energy that could be stored in a standard Lithium-ion battery. Improvements to the efficiency of batteries and the system as a whole allowed for storage of up to 120kW of energy, which could be imagined as the car having a second engine with which it could push itself faster, or reduce its fuel consumption, or both. An alternative to the storage of electrical energy is the flywheel, which is a pure mechanical device, and which functions by using the braking wheels to rotate it, and soon after braking, when acceleration was required, the flywheel could be used to turn the drive train of the car to achieve the much-needed boost. Imagine this as a hand that pushes a sprinter from behind to give him additional speed and power. The KERS system is unlike traditional feedback boosters, such as, the supercharger or the turbocharger, which derive power at the cost of that available to the wheels of the car while it accelerates. The KERS system lies dormant until the time the car brakes, at which point it charges itself, kicking in any time after the charge is stored electrically or mechanically allowing for the smooth and elevated acceleration of the car. Also, the KERS technology provides clean energy, thereby reducing the consumption of fossil fuels by up to 15%.

Fig 2: Illustration of the technology (Courtesy: The Internet)

Usage in production vehicles

Although the KERS system was discontinued in Formula One due to various reasons, a few of them being the excess weight and volume adding to the car, and a few untoward events of electrical shocks and fire while testing the system, it has enjoyed its use in production vehicles since then. Over 5000 of London buses have been fitted with devices based on the KERS technology, and have since then enjoyed substantial fuel efficiency. Also, the luxury car manufacturing giant, Volvo, has introduced KERS into their top-of-the-line flagship XC90 line of luxury SUVs in the year 2020, promising their customers 15% fuel efficiency. (Link)


While the whole world is clamoring for renewable energy alternatives for fossil fuels, and while battery technology enjoys constant improvement through continued research, the significance of moving power generation from large farms to smaller and more manageable spaces like the home, and the car, has fortified the case for KERS, which is sure to champion the cause of taking clean energy to reality. While many alternative energy technologies boast of extraordinary and complicated systems, the questionability of efficiency and maintainability has hence given KERS, which is based on simpler technology and implementations, the well-needed thrust, which could well propel the automotive industry to greater heights, what with electric cars already gaining acceptability. So, an electric car that charges your battery while you brake is sure to reduce your visits to the charging station, right?


Navsar is a progressive business house offering a bouquet of services and solutions for the Power & Infrastructure industry. Since our founding, Navsar has advised, executed, and managed a diverse set of Conventional, non-conventional power projects. Working with professionals from top-tier EPC and Consulting firms, Navsar aims to improve the efficiency, effectiveness, and value of clients’ assets.

Visit to know more about our services and email to know how we have been helping our clients.

Leave a Reply