As of now, there was no successful matter-antimatter reaction. So any predictions that it could be close to 100% are, for now, gedanken.
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Question is, then, how are you going to obtain hydrogen? Buying it will again cost much more then just powering your systems from municipal grid. Producing it? It introduces energy cost that must come from somehow.
So no matter how you slice it, using hydrogen to power your house is NOT cost-effective. So why bother with inefficient setup? I could understand building one for scientific research into efficiency, but setting it up to be "independant" from municipal grid is flat-out silly.
Again, if independence is your goal, then gasoline generator is your best bet. Or a good long foray into installing solar panels/geothermal setup/wind turbine/whatever.