The hydrogen produced could be used as a transportation fuel.

Hydrogen is high in energy, yet an engine that burns pure hydrogen produces almost no pollution.

The hydrogen produced will cost two to three times the price of petroleum.

Usually, the electricity consumed is more valuable than the hydrogen produced so this method has not been widely used.

When employed in a fuel cell, that hydrogen can also produce electricity, recovering half of the water previously consumed.

The fuel cells use this hydrogen to produce the electricity that runs the vehicle.

And it makes a lot of sense when you think about it, because hydrogen produces zero emissions.

Acetate and hydrogen produced in the first stages can be used directly by methanogens.

Hydrogen can also be produced by splitting apart water atoms, but that takes more energy than the hydrogen will produce in the fuel cell.

The lithium-water reaction at normal temperatures is brisk but nonviolent, as the hydrogen produced will not ignite on its own.