Jalopnik Pretty amazing stuff. It it pretty cool when you think about the opportunities that this presents. "Larger" engines in a smaller space.... built up air for turbo spool.... cool stuff
This isn't exactly in response to this video, but I feel stupid making another thread for it... So from what I understand, the main reason city driving = lower mileage is because it takes a good bit of energy to get the car from dead stop -> up to speed, right? Well, a car engine already has an air compressor... the cylinders, right? Would it be possible to use the cylinders / pistons during braking to compress air, which would be stored in a tank, and then forced back into the cylinders instead of burning fuel? I imagine it would be complicated, but even if the compressed air from braking only got you going from a dead stop to 10 mph before it exhausted the pressure, wouldn't that still be better than using gasoline? Please feel free to ridicule this terrible idea.
It isn't a terrible idea, it just doesn't work that way. Even on decel, you are burning gas. You definitely don't want to shove exhaust cycle gasses into a compressed chamber for any kind of use. The particulates in the exhaust gas wont play nicely with a precision air compression and release system. What we do have is regenerative braking on hybrid systems. Where the act of braking builds charge to use during the electrical cycle of a hybrid engine/motor system.
Oh, I assumed rolling to a stop with the car in gear and the clutch engaged burned zero fuel. If that's not the case, then that definitely eliminates my idea as a possibility. I'm aware of the regenerative braking with hybrids, but the main reason hybrids have zero appeal to me in their current state is the extra weight of batteries.
