- Sunday, 29 March 2009
This year grand prix racing featured a brand new technology, which in thoery makes the cars more environmentally friendly. Kinetic Energy Recovery Systems or KERS for short are devices used for converting some of the waste energy from the braking process into more useful types of energy which can then be used to give the cars a power boost.
It all sounds very complicated but it really isn't, the basic physics of KERS is laid down in lessons taught to almost every secondary school child in the developed world. It is all based around the fact that energy cannot be created or destroyed, but it can be endlessly converted. When you drive down the road your car has kinetic energy, when you brake that kinetic energy is mostly converted into heat energy (why is why fast cars need to keep thier brakes cool). In most cars that heat energy is wasted, but in a KERS equipped car that is not the case. When the driver brakes most of the kinetic energy (or rotational force) is still converted to heat energy but a portion is treated differently and is stored up in the car. When the driver presses his boost button that stored energy is converted back into kinetic energy and under the current F1 regulations gives the car about an extra 85bhp for just under seven seconds. The following short video from Red Bull walks through the process amongst other new regulations
Electronic KERS
There is more than one type of KERS in fact there are a number of types, the Red Bull RB5 uses an electronic system supplied by Italian firm Magneti Marelli. This is in fact the common system in F1, used by Red Bull, Toro Rosso, Ferrari, Renault and Toyota. 
When the car brakes a proportion of the rotational force is captured by a electric motor / generator (MGU) mounted at one end of the engines crankshaft. This MGU converts the kinetic energy into electrical energy which is then stored in batteries. When the driver presses the boost button the electrical energy in the batteries powers the MGU - which puts an extra 85bhp into the engine. You can hear this happening on the onboard cameras as the engine note suddenly jumps up for a few seconds, especially coming out of corners. The diagram below details the Marelli system and the picture to the right shows the Motor Generator Unit. Each team has a slightly different spec of MGU - all slightly smaller than the one pictured here but the construction is identical.
One of the toughest elements of electronic KERS is how to store the electrical energy, most of the teams use a lithium battery, not dissimilar to those used in mobile phones (just a lot bigger). But just like the battery in your phone when you charge the battery it gets hot so many of the KERS cars feature additional ducting to cool the systems. BMW however has taken a different approach by using devices known as super-capacitors instead of batteries, these run cooler and are arguably more efficient
For a more in depth look at the technology of electronic KERS click here: F1 KERS
Electro-Mechanical KERS
Williams have approached the energy storage problem in a totally different way, rather than fitting batteries or capacitors, they use a large flywheel. Ian Foley who inevented the system explains in this short video
For a more in depth look at the technology of electronic KERS click here: Williams F1 KERS
A number of non electrical systems have also been developed for F1, most notably the Flybrid, designed by former Renault F1 engine boss Jon Hilton. The system is based on a flywheel and operates totally differently from the Electronic and Williams systems. McLaren and Force India are both believed to have investigated similar systems. McLaren also developed a all hydraulic KERS in 1998 and ran it in testing before it was banned by the FIA. More basic information can be found here: Mechanical F1 KERS
An in depth look at the Flybrid F1 KERS can be found here: Flybrid F1 KERS
Further reading
More F1 technical information can be found here: Racecar Engineering F1
Martes, 31 Marzo 
