Im a mechanical engineer and was curious to know if its viable to produce hydrogen from reacting silicon nanopowder with water to produce SiO2 and H2.  No heat is required.  I calculated that 1 kg of the silicon powder can produce about 89 g of hydrogen.  I also know that 1 kg of Hydrogen has the equavalent energy of 1 gallon of gasoline.  So the question is if its cost effective to make hydrogen this way.