Is Hydrogen a practical way to store energy and create fresh water? Consider this scenario: There is an island lacking a fresh water source. So you build some off-shore wind turbines. The electricity doesn't go far - just into the salt water at the turbine's base, where it uses Electrolysis to create hydrogen. The hydrogen then goes through a pipe to a high peak on the island. When power is needed, it is converted back to electricity, and water is created as well. Would a tank of hydrogen hold enough to offset times when there is no wind? Would water created by hydrogen (fuel cells? Combustion?) be fit to drink? How much power is lost in turning electricity into hydrogen and back?