Let me start off by saying that I understand conservation of energy and the laws of thermodynamics. I know you can't use water for fuel, and you can't power a semi-truck soley on hydrogen produced by an onboard electrolyzer. But... I have read quite a few claims that using an onboard electrolyzer, and flowing that hydrogen into the air intake will increase the fuel mileage. Is there any mechanical engineering explanation for why this would or wouldn't work? (ie - does the alternator not produce enough electricity? or does it overproduce electricity which is why it allows for some extra to be used in the electrolysis?) Or how efficient it would be? based on a chemical explanation?