MotoGPmatters.com (aka KropotinThinks) reported on the efforts of KTM (warning: poor, resource-burdening flash site) to implement a Kinetic Energy Recovery System on their 125 cc Grand Prix machines. Kropotkin cites a report by the Spanish motorcycle website Motosolo describing a system used last fall in the race at Valencia and again during testing this winter at the same circuit. The system uses a capacitor rather than a battery to store energy during braking and can reintroduce approximately 2.5 HP for use when needed. It may be surprising to find efficiency enhancing technology applied to a class of machines that is already known for being relatively more fuel efficient efficient than other forms of transport but that 2.5 HP could really come in handy when tenths of seconds count.
While exciting new hybrid and electric scooters and concept vehicles have been reported here in the past, they have their challenges and barriers to widespread implementation. One of the biggest problems for both all electric plug-ins and hybrids like the Toyota Prius is the cost, weight and disposal of large toxic chemical-laden batteries. The use of a smaller energy storage unit like a capacitor could be a strategy to not store so much energy where one could drive for extended periods of time without combustion, but to assist a motor at specific points in vehicle use. The energy that normally would be wasted as heat during braking could be harnessed to turn near useless engine applications such as a small four-stroke engine that can’t get out of it’s own way in traffic into a useful machine. Where tenths of seconds count in racing, they may be even more important when that cab driver decides his lane position is more important than your life. The increase in efficiency may allow internal combustion engines to be designed smaller and less powerful knowing that some other stored energy could be used on-demand. One could even envision a 25cc four stroke with a capacitive KERS system that could navigate urban traffic and get 150 mpg!
Interesting. Capacitors are light and durable and the short-term energy storage idea they envision might be feasible. I one kicked around a similarly-motivated idea for a spring inside an enclosed rear moped wheel which would, wind up as the rear brake was pressed, provide a boost as the machine accelerated from a stop, and freewheel otherwise. I bet my idea could be mass-produced way cheaply. It wouldn’t be any use for squirting in traffic, though. Hmm…