The good thing about a hydrogen setup is that you can store a lot more energy so that there's more useable power as compared to batteries. It's the same idea as using hydrogen to power cars, it allows for extended range because the storage medium has a pretty high energy density. At home it would be easy to have larger storage tanks, so pressure would not have to be as high as in a car, but in theory if you had a compressor it would be possible to use the hydrogen in a FCV.

2001 Prius Photos       2005 Prius Photos
'97 Prius Simulation Prius inner workings