Andrew,

As a former member of Society of Automotive Engineers, International, I'd recommend that you join the SAE. SAE International They have a good student program and most automotive related businesses are members.

Another non-automotive publication that I have used for years is the NASA Tech Briefs website. Subscribe

DARPA Defense Advanced Research Projects Agency is another good source of leading edge technology, not just for autos.

Good luck.

Formula One race cars have used KERS on their cars. McClaren Mercedes developed a system that provided somewhere around 45 BHP boost for four seconds, but could have been used many times per lap. The FIA rules governing KERS, allowed teams to use KERS to draw 60 Kw of energy from the rear axle of the car, which could be stored up to 111 watt hour of energy per lap. It allowed the drivers to use 60Kw (82 hp) for 6.6 seconds per lap. Since all of the teams used the technology, I don't think it would be proprietary information. You might want to Google "Formula One/KERS" to read the article. Today's Formula One racing programs provides tomorrows automotive technology, and I'm sure this particular application will find its way into the hybrid auto applications. Happy reading.

Hi Andrew,

I scanned your paper quickly, and think it is a nice summary of KERS. You mentioned a 70% efficiency number. This is only very slightly higher than the efficiency for an average electric system (and about equal to the round trip efficiency for a very efficient electrical system in which the motor is 95% efficient, the controller 95%, and the battery 90%[rt].) An electric system does not require the expense of a CVT and the complicated controls required to smoothly mix power delivery from a very high speed flywheel (50,000 rpm or more to be adequately light) and a low speed engine.

In systems like the Prius hybrid system, where the fundamental principles are 1. to run the engine at closer to its efficiency peak all the time, and 2. to make up for a small, efficient engine with supplemental power, then regen comes essentially for free: you already have all the components required.

Consider the simplest imaginable toy battery-powered electric car in which the battery is wired directly to the motor, with only a switch in between. Push that car faster than its normal running speed, (or point it down hill) and regen occurs automatically. It's that simple.

Increasingly sophisticated electronic controls continue to go down in price (real dollars) over time. But sophisticated mechanical systems generally trend upward. So despite the fact that KERS systems (and flywheel-powered buses, etc) have been considered for decades by manufacturers, they have not been implemented economically. That's why we see them used in Formula One, and not in Priuses.

Flywheels are used in some UPS systems, which is a more practical application (than in cars) because the system does not need to be so light (and therefore can run slower, using less costly bearings) and the bearings do not have to deal with the gyroscopic forces incurred when the vehicle attitude changes.

There is a lot of info on KERS systems on the web, and perhaps there is a future for such systems in cars. But electrical systems have such a huge lead (already being on the market in the millions) that I don't expect to see widespread application of mechanical systems. There have also been hydraulic systems, as used in UPS trucks. But a 1000 lb hydraulic tank stores about as much energy as the 100 lb battery pack in a standard Prius, and the system cost is higher.

I don't see a breakthrough on the horizon that will make mechanical systems competitive with electrical systems. But I don't say that to be discouraging. You could be the one to come up with that breakthrough.