THE KERS:AN ENERGY RECOVERY SYSTEM IN THE AUTOMOBILEIsaac Duroher – MI3

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Low Energy Light bulbNeon Light

Radiator @Cyclist in full effort

Can you guess how much power (in kW) the following consume?80 Horsepower City Car59 kW

Only 35% of the combustion energy of an engine is used for propulsion.80 Horsepower City Car59 kW 38kW go to waste

The energy lost by all cars in France approximately 44.3% (nearly 500 GWh/day) of the electrical energy produced by the entire French nuclear fleet!• 1kW=one thousand (103) watts• 1GW=one billion (109) watts

= parc nucléaire

Tires BrakesRadiator Shock Absorbers

Engine Exhaust pipe

Where do all these losses take place?

Thermal energyKinetic energyBrakes

The SolutionRecover and reuse the wasted energyKinetic energy recovery system (often known simply as KERS )How?

• Recovers kinetic energy generated by the braking• Recovered energy  is stored in a reservoir flywheel flywheel KERS high voltage batteries battery KERS

• Invented in 1950 by American physicist Richard Feynman

Flywheel=volant d'inertie

Flywheel KERS

carbon fiber rim (either a ring or tube)

clutch=embrayage

• Advantage: no conversion of the energy in another form This reduces the inevitable losses during the mechanical / electrical conversion

• Disadvantage: weight and bulk.

Flywheel KERS

=encombrement

3D view of the previous picture

Yield and industrial applications• Formula 1 : 400 kJ issued by the KERS the equivalent in petroleum: 0.021 liter/lap 1.47 liter/Grand Prix• Volvo: considering a 20% reduction in fuel consumption

Flywheel KERSYield= rendement

Battery KERS

The crankshaft (1) is "boosted" by an electric motor (3) that is supplied by a battery (2)vilebrequin

• Advantages: lighter and more compact than the flywheel KERS. • Disadvantages: the battery can be pretty heavy battery life reduced because of the rapid charge and discharge.

Battery KERSIndustrial application: Formula 1

What energy? Where ? How? Conversion ? Storage ? Use? Yield?Recover the lost energyMecanical EnergyBraking systemKERS

(most common)Mecanical to electrical energyBatteryRestart or accelerateNo info foundNo conversionFlywheelRestart or accelerate0.8 for 15 minExhaust GasesTurbo-compoundMecanical to electrical energyBatteryIncrease engine’s powerFuel savings of 10%

Tires & SuspensionPiezoelectric microsystems (MEMS)Pressure energy to electricityNo info foundSupplying power to autonomous sensorsAt 70 km / h, producing

42 microwatts.Shock AbsorbersVibrations to electricityBatteryPower electronic componentsReduced consumptionby 2 to 10%ThermalEnergyExhaust pipes and radiatorRankine CycleThermal to mecanical energyBatteryPower electronic componentsFuel savings of 10%

Direct heat utilizationNo conversionNo storageHeat the cabinNo info foundDecrease the engine warm-up timeNo info found

Thermo-electricityThermal to electrical energyBatteryPower vehicle & electronic componentsGain of 5% to 10% of

fuelShape-memory alloyThermal to mecanical then electric energyNo storagePower electronic componentsNo info foundOther existing systems

Other existing systems

Shape memory alloys

Thermoelectricity

energy recovery shock absorber

Rankine Cycle

Turbocompound

Piezoelectric microsystems

Thermal to mecanical

energy

Pressure energy to electricity

Thermal to electrical energy

Mecanical to electrical

energyVibrations

to electricity

Thermal to mecanical

then electric energy