>>>Does anyone know how much energy is needed to extract hydrogen from water?
Exactly as much as when you recombine it in a fuel cell minus thermal, and resistive losses, and far more than you would get out burning it in a
reciprocating engine.
>>>Can someone tell me why that idea would not work?
Because you can't get more energy out of a system than you put in.
If the device could deliver overunity the inventor would be walking across the stage to pick up his Nobel Prize, not hawking tin cans on the
internet.
>>>Would more energy be needed for hydrogen extraction than the alternator could produce?
Of course it would, otherwise everyone would have one in their car.
Many different water fuel devices have been around, and the only one that seems to work is the
Pantone GEET, and it simply uses more of the thermal energy for expansion, and captures
most of the waste fuel in the exhaust.
It is not a free energy machine, but you can get much better efficiancy with it in the right situation.
I don't think it would work well with a modern car.
All the sensors and computers can get all confuse with simply a lose wire, let alone a major mod like this.