With gasoline prices once again rising, attention is turning to engine variations to increase mileage and efficiency. The ethanol boosted, turbocharged gasoline engine combines a number of well known, current technologies for substantial improvement in mileage at lower cost and complexity than with a hybrid.
Two fellows at MIT came up with the idea of using both turbocharging and high compression on a small engine, which would give you a lot of power but would quickly lead to detonation. Their answer is to add direct ethanol injection whenever knock would otherwise occur. The ethanol injection would, in effect, raise the octane rating of the fuel to 130, eliminating knock allowing the high compression plus turbo to work. The turbo only kicks in when extra power is called for. Because of the power gained from both turbo and high compression, the engine size could be halved and still get equivalent performance.
They calculate 30 percent higher efficiency than a standard engine, just slightly less than a Prius, without the added complexity of the hybrid drivetrain or the need to replace any batteries. The added cost of this system would be $500- $1000 per vehicle, far less than the $5000+ cost differential for a hybrid.
This system does require a separate ethanol tank but the amount used is very small and would only require refilling every 2 or 3 months, similar to an oil change interval. The size of the ethanol tank in a car would be only 2 to 6 gallons.
Everything in this system is already standard technology found on many modified motorcycles, the amount of ethanol necessary for this setup on a motorcycle would be very small. If manufacturers like Yamaha are tinkering with hybrid motorcycles like the Gen-Ryu, they could do something like this quite easily. Whether this system would make sense on a motorcycle is open to debate, but then, so are hybrid motorcycles.